Shaping Circularity in the Food Industry: Strategic Pillars Enabled by Biorefinery Systems

1

You mention the institutional debate, but the key strategies—especially at the international or European level—do not appear. Could you include these strategies?

Thank you for your comment. We felt it was important to include some European initiatives, indeed. We've added the following passage to the introduction:

“Internationally, circularity has progressively moved from a conceptual aspiration to a political priority, particularly in the European Union. Major initiatives such as the European Green Deal [13], the Circular Economy Action Plan [14], and the Farm to Fork Strategy [15] frame the transition of food systems as a central component of climate-neutrality and sustainable-growth agendas. Instead of treating waste reduction and resource efficiency as isolated objectives, these programs advocate a systemic reshaping of agri-food chains, encouraging the cascading use of bio-based resources, the valorization of biomass, and the incorporation of bioeconomy principles at all stages of production and consumption. In parallel, the Sustainable Development Goals [16] reinforce the need to align food production with broader commitments to conscious consumption (SDG 12), climate action (SDG 13), zero hunger (SDG 2), and partnership-driven transformation (SDG 17). However, while these strategies define an institutional direction, translating political objectives into industrial-scale implementation remains a constant challenge”.

2

The concept of “integration between operational management and environmental governance” deserves more attention, since many still associate Circular Economy only with environmental aspects. Could you further develop this discussion?

Thank you very much for your suggestion for improvement. In that regard, we have added to the theoretical framework, which is presented below:

The coordination between operational management and environmental governance deserves special clarification, since the circular economy is still frequently interpreted as an environmental agenda oriented on waste and emissions. The circular transition of agri-food systems requires adopting environmental criteria into operational planning, supply chain coordination, and performance measurement frameworks, rather than treating sustainability as an external layer of compliance [30,38]. From this perspective, governance mechanisms must align strategic sustainability commitments with day-to-day production decisions and material-flow management. In this way, the circular economy operates as an integrative management logic that synchronizes ecological performance, economic viability and organizational supervision within industrial systems [39,40].

3

You refer to cultural changes aimed at conscious consumption, but you do not explicitly address circular consumption, which has recently gained increasing attention in the food domain, including issues related to the citizen-consumer and people–policy gaps. Could this dimension be included?

We thank the reviewer for this valuable suggestion. We agree that the concept of circular consumption is increasingly relevant in the food domain and deserves explicit consideration. In response, we have expanded the discussion on consumer behaviour in Section 2.2.

The revised text now incorporates the role of information—particularly digital sources—in shaping consumer awareness and attitudes toward responsible and circular food practices. This addition highlights that, although access to information can enhance environmental knowledge and improve the perception of innovative or circular products, it does not necessarily lead to consistent behavioral change. By doing so, we explicitly address the gap between pro-sustainability attitudes and actual consumption practices, which is closely related to the concept of the citizen-consumer and the so-called people–policy gap.

This revision strengthens the manuscript by linking circular consumption to the broader behavioral and informational dynamics that influence the adoption of circular economy practices in the food sector. Here is the excerpt that was elaborated:

In this context, access to information, particularly digital sources, is essential for shaping consumer awareness and attitudes towards responsible food practices. When consumers have access to information, they can significantly expand their environmental knowledge and become more likely to adopt innovative or circular products; however, this does not necessarily imply consistent behavioural change, as decision-making remains influenced by trust, perceived risks, and contextual factors [47].

4

You mention Life Cycle Assessment (LCA), but it is not the only tool used. Could you include other relevant tools?

We thank the reviewer for this valuable suggestion. In response, we have expanded the discussion in Section 2.2 to include additional tools commonly applied in circular economy assessments. Specifically, we incorporated Material Flow Analysis (MFA) and Life Cycle Cost Analysis (LCCA), highlighting their complementary roles alongside Life Cycle Assessment (LCA) in capturing environmental, material, and economic dimensions of circularity. We also emphasized the use of the Product Environmental Footprint (PEF) as an integrated framework for comparing environmental performance across food categories. This addition strengthens the manuscript by providing a more comprehensive and systemic perspective on the evaluation of circularity in the food industry.

“To simultaneously parameterize the environmental, material, and economic dimensions, the Material Flow Analysis (MFA) and Life Cycle Cost Analysis (LCCA) tools are also being used. While MFA enables assessing resource efficiency and material circulation within food systems, LCCA helps evaluate the economic viability of circular strategies over time [48–50]. In addition to the tools, it is worth highlighting the Product Environmental Footprint (PAP), which, in turn, enables comparisons across food categories using integrated performance indicators, such as resource use, energy intensity, and waste reintegration [51]”

5

What search string was used in the review? Please include it to ensure the study’s replicability.

We thank the reviewer for this important observation. In response, we have clarified the search strategy by explicitly presenting the search string used in the Scopus database. The keywords were organized into two groups (circular economy and food-related terms), combined using Boolean operators (OR within groups and AND between groups). This information is now clearly described in the methodology section, and the search process is also illustrated in Figure 1. These additions improve the transparency and replicability of the study. The highlighted excerpt follows below:

“The corpus selection phase was carried out in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) protocol [60], which is known for ensuring transparency, traceability, and replicability in systematic reviews, including qualitative research. The research was conducted on the Scopus platform, using Boolean operators in the document title and keyword fields. The terms used were: “circular economy” OR “circularity” OR “circular design” AND “food production” OR “food industry.” The inclusion criteria were defined as articles and reviews published between 2019 and 2024, written in English, and categorized as scientific documents (such as articles or reviews), as shown in Figure 1. Duplicate content, texts unrelated to the food industry, and documents that were not available for full reading were removed”.

6

It is not clear which flow was followed to identify the final set of papers. Systematic reviews usually include a flow diagram with explicit exclusion criteria. Could you provide more details about the selection process?

We thank the reviewer for this valuable observation. We would like to clarify that this study does not aim to conduct a formal systematic literature review, but rather a qualitative content analysis based on a structured and transparent document selection process.

To improve clarity and transparency, we have incorporated a flow diagram based on the PRISMA framework (Figure 1), which illustrates the identification, screening, and selection stages of the document corpus, including the applied inclusion and exclusion criteria. The revised manuscript also provides a more detailed description of the selection process, including database choice, search strategy, and filtering steps.

These additions enhance the transparency and traceability of the study, while maintaining its methodological positioning as a content analysis rather than a systematic review.

7

Could you clarify the criteria mentioned, specifically:

• What constitutes “minimum theoretical and empirical adherence” to the topic?
• How was the connection between circularity practices and the food industry operationalized?
• How was the number of citations used as an indicator of scientific impact?

We thank the reviewer for this important request for clarification. In response, we have refined the description of the selection criteria in Section 3, particularly in the paragraph on the final selection of documents. We clarified that “minimum theoretical and empirical adherence” refers to studies that explicitly address circular economy practices within the food industry, either conceptually or empirically. We also detailed how the connection between circularity and the food sector was operationalized by identifying themes such as resource recovery, waste valorization, and circular production strategies in agri-food systems. Finally, we specified that the number of citations was used as a complementary indicator of scientific relevance, without being applied as a strict exclusion criterion. These additions improve the transparency and rigour of the methodological approach.

8

In the table, the acronym “ODS” appears. Should it be “SDG”?

We thank the reviewer for pointing this out. The acronym has been corrected from “ODS” to “SDG” throughout the manuscript to ensure consistency with the English terminology.

9

In the section describing the methodological steps, several parts are quite generic—for example, the statement “the gap was identified.” Could you clarify how this gap was identified?

We thank the reviewer for this important observation. In response, we have clarified in Section 3.1 how the research gap was identified. Specifically, we now indicate that the gap emerged from the critical analysis of the literature presented in the Introduction, which highlights the fragmentation of existing studies on circular economy in the food sector. These studies often focus on isolated practices, technologies, or decision-making processes, with limited integration between strategic frameworks and operational infrastructures. This clarification strengthens the transparency and coherence between the theoretical background and the methodological steps. The highlighted excerpt follows:

“Subsequently (Stage B), a scientific gap was identified through a critical analysis of the literature presented in the Introduction, which revealed persistent fragmentation in studies on CE in the food sector. In particular, previous research tends to address circular practices, waste management, or technological solutions in isolation, with limited integration between strategic frameworks and operational infrastructures, especially in relation to biorefinery systems and their alignment with the SDGs”.

10

Do you believe that the SDGs ultimately linked to Circular Economy are only the ones reported? Could you justify this selection?

We thank the reviewer for this important question. We would like to clarify that the SDGs identified in this study are not intended to represent the only goals related to the Circular Economy. Rather, they correspond to the most frequently cited circular practices in the analyzed literature.

The selection was based on the content analysis conducted in this study, in which the structuring elements identified in the selected documents were systematically associated with the SDGs based on their thematic alignment. The resulting set of SDGs reflects the most recurrent and strongly connected goals within the context of circular economy practices in the food sector. Therefore, the findings should be interpreted as an empirical mapping of the literature rather than an exhaustive or normative classification of all possible SDG–CE relationships. Here is the section in the text where we provided this clarification:

Based on this information, we moved on to Stage J, where the elements identified in the previous steps were organized in a categorization matrix guided by the SDGs. Each structuring element was associated with the 2030 Agenda goal(s) that best reflected its nature and intended function. The SDGs identified in this study represent those most frequently associated with circular economy practices in the analyzed literature and should not be interpreted as an exhaustive set of all possible CE–SDG relationships. Rather, they reflect an empirical mapping derived from the recurrence and thematic alignment of the structuring elements identified through content analysis. For example, sustainable agricultural practices and the use of waste as a protein source were associated with SDG 2 (Zero Hunger and Sustainable Agriculture); actions aimed at valorizing waste for bioenergy were linked to SDG 7 (Affordable and Clean Energy); and actions focused on reducing waste and reusing food were associated with SDG 12 (Responsible Consumption and Production), among others.

11

Papers published in 2025 were not considered. While redoing the analysis may not be necessary, could the introduction or discussion be updated to include recent studies?

We thank the reviewer for this valuable suggestion.

In the revised version of the manuscript, recent studies published in 2025 have been incorporated into the Introduction and Discussion sections in order to update the state of the art and reinforce the relevance and timeliness of the research topic.

It is important to note that the methodological scope of the study—particularly the definition of the analytical corpus—remains unchanged, as it was intentionally delimited to ensure consistency, transparency, and replicability of the content analysis. Therefore, the inclusion of 2025 publications was intended solely to complement the theoretical framing and discussion, without altering the original dataset or the analytical procedures.

This adjustment allows the manuscript to reflect recent developments in the field while preserving its methodological rigor.

12

Are citations written as “[18] systematized” correct? Should they instead follow the format “Oliveira et al. [18] systematized”?

Thank you for this observation. We have revised the manuscript to improve consistency in citation style, particularly in cases where references are integrated into the sentence structure. In these instances, the corresponding authors are now explicitly mentioned. For example, we have updated the text to read “According to Bardin (2011) [54]…” and “as indicated by Elo et al. (2014) [59]…”. These adjustments ensure greater clarity and alignment with standard academic writing conventions.

13

In some descriptions, the “Agri” component is neglected, although the main pillars appear to relate to the entire agri-food system rather than only the food industry. Could you clarify and adjust the scope accordingly?

Thank you for this insightful comment. The primary focus of this study is on the food industry, as defined by the research scope and search strategy. However, we acknowledge that circular economy practices in this sector are inherently connected to broader agri-food system dynamics, particularly in aspects related to biomass supply, by-product flows, and upstream resource management.

To address this point, we have revised the manuscript to clarify the analytical scope, emphasizing that while the proposed pillars are grounded in the food industry context, they may also interface with upstream agricultural activities where relevant. These adjustments aim to improve conceptual clarity and avoid potential ambiguity regarding the level of analysis. The highlighted excerpt follows:

“While this study focuses on the food industry, it is important to acknowledge that several circular practices described here interact with upstream agricultural processes, reflecting the interconnected nature of agri-food systems”.

14

The paper appears to have been previously reviewed. What changes were made in this revision? Please mark all modifications in red (or otherwise clearly highlight them).

Thank you for this observation. The manuscript has undergone two rounds of revision. To ensure clarity, we have used a color-coding system to distinguish the changes made in each stage. Specifically, revisions from the first round are highlighted in yellow, while the modifications introduced in the current revision are marked in green. This approach was adopted to allow a clear identification of the updates made in response to the reviewers’ comments at each stage.

15

What is the actual aim of the research?

Is it:

• “This review consolidates recent advances on Circular Economy (CE) strategies in the food industry, with particular attention to the valorization of residues and by-products as high-value resources”?

or

• To address the scientific gap through the guiding question:
  “How can the circular transition in food production be fostered through strategic pillars that guide its implementation?”
  with the objective of proposing pillars for implementing circular practices in food production aligned with the SDGs?

Please clarify the main aim of the study.

We thank the reviewer for this important clarification request. The main aim of the study is to propose strategic pillars for implementing circular economy practices in the food industry, addressing the identified research gap related to the lack of integration between strategic frameworks and operational infrastructures, particularly biorefinery systems. The literature review conducted in this study serves as the analytical foundation for identifying and consolidating relevant structuring elements, which are then systematized into the proposed pillars. Therefore, the review component supports the primary objective rather than serving as an end in itself. To improve clarity, we have revised the manuscript to explicitly distinguish between the supporting role of the literature analysis and the main objective of proposing strategic pillars. Here is the improved excerpt:

To address this gap, this study asks: How can the circular transition in food produc-tion be fostered through these strategic pillars, and how can biorefinery infrastructure strengthen them at scale? Accordingly, the main objective of this study is to propose stra-tegic pillars for implementing circular practices in food production, while specifying how biorefinery systems can operationally reinforce biomass valorization and bioorganic value chains aligned with the Sustainable Development Goals (SDGs) 2, 7, 9, 12, 13, and 17. To support this objective, the study consolidates and analyzes recent advances in CE strate-gies in the food industry, especially those related to the valorization of residues and by-products.

16

The aim stated in the Abstract and the Introduction should be consistent. Please ensure both sections present the same research aim.

Thank you for this valuable observation. We have revised the Abstract to ensure full consistency with the research aim presented in the Introduction. Specifically, the Abstract now clearly states that the primary objective of the study is to propose a conceptual framework structured around strategic pillars for implementing Circular Economy practices in the food industry. The description of the literature analysis has been maintained as a supporting methodological approach, ensuring alignment between both sections.

Abstract: “In this context, this study proposes strategic pillars for circular practices in the food industry, with an emphasis on the transformation of waste and by-products into high-value-added resources through bio-based processes supported by biorefineries, in line with the Sustainable Development Goals (SDGs)”.

Introduction: “Accordingly, the main objective of this study is to propose strategic pillars for implementing circular practices in food production, while specifying how biorefinery systems can operationally reinforce biomass valorization and bioorganic value chains aligned with the Sustainable Development Goals (SDGs) 2, 7, 9, 12, 13, and 17. To support this objective, the study consolidates and analyzes recent advances in CE strategies in the food industry, especially those related to the valorization of residues and by-products.”

17

What is the research hypothesis?

Thank you for this question. This study does not adopt a hypothesis-testing approach, as it is grounded in a qualitative, exploratory, and descriptive design based on content analysis. The research is oriented toward theory building, aiming to identify, organize, and systematize key elements of Circular Economy practices in the food industry. Accordingly, the study is guided by a research question rather than a formal hypothesis.

18

How was the hypothesis verified or tested in the study?

As the study does not involve hypothesis formulation, no hypothesis testing was conducted. Instead, the research follows a qualitative analytical process, in which data from the literature were systematically collected, categorized, and interpreted through content analysis. This process enabled the identification of recurrent elements and their subsequent organization into strategic pillars, forming the basis of the proposed conceptual framework.

19

The analysis of sustainable development is important; however, the results of sustainability measurement are not evident. While describing SDGs is useful, what is the actual sustainability value or impact demonstrated by the study?

Thank you for this insightful comment. We agree that sustainability measurement is an important dimension. However, the purpose of this study is not to quantify sustainability performance through specific metrics, but rather to contribute at a structural and strategic level by identifying and organizing key elements that enable the implementation of Circular Economy practices in the food industry.

The sustainability value of this study lies in the development of a conceptual framework structured around strategic pillars, which provides actionable guidance for organizations to improve resource efficiency, reduce waste generation, enhance biomass valorization, and strengthen circular supply chains. These contributions directly support sustainability outcomes by facilitating the operationalization of practices aligned with the Sustainable Development Goals (SDGs), particularly in areas such as responsible production and consumption, renewable energy use, and climate action.

To clarify this point, we have revised the manuscript to better emphasize that the study contributes to sustainability by enabling implementation pathways and decision-making support, rather than by providing direct quantitative measurement of impacts. To convey this message to readers, we included the following excerpt in the conclusion of the manuscript:

“In this sense, it is important to emphasize that the sustainability value of this study does not directly measure environmental or social performance indicators, as it is limited to supporting the implementation of CE practices. By structuring and systematizing key elements, the study enables organizations to improve resource efficiency, reduce waste generation, and strengthen circular value chains, thereby achieving more effective sustainability outcomes in practice”.

20

Beyond listing SDGs, what concrete contribution to sustainability does the research provide?

Thank you for this insightful comment. We agree that simply associating findings with the SDGs is not sufficient to demonstrate a concrete contribution to sustainability.

The contribution of this study lies in developing a conceptual framework structured around strategic pillars that enable the practical implementation of Circular Economy principles in the food industry. Rather than focusing on measuring sustainability outcomes, the study advances sustainability by identifying, organizing, and systematizing key elements that support decision-making and operational integration. Specifically, the proposed framework provides actionable guidance for organizations to improve resource efficiency, reduce waste generation, enhance biomass valorization, and strengthen circular supply chains. In this sense, the study contributes to sustainability by facilitating the translation of fragmented knowledge into structured implementation pathways, which can support real-world improvements aligned with the SDGs. To clarify this point, we have revised the manuscript to better emphasize the study’s contribution's implementation-oriented nature. To emphasize this idea, we added the following passage in the introduction and the conclusion:

“To address this gap, this study asks: How can the circular transition in food production be fostered through these strategic pillars, and how can biorefinery infrastructure strengthen them at scale? Accordingly, the main objective of this study is to propose strategic pillars for implementing circular practices in food production, while specifying how biorefinery systems can operationally reinforce biomass valorization and bioorganic value chains aligned with the Sustainable Development Goals (SDGs) 2, 7, 9, 12, 13, and 17. To support this objective, the study consolidates and analyzes recent advances in CE strategies in the food industry, especially those related to the valorization of residues and by-products”.

“The proposed pillars provide practical guidelines that managers and professionals in the sector can operationalize to reduce waste, valorize residues, foster territorial partnerships, and incorporate regenerative technologies. In doing so, it contributes to the materialization of commitments aligned with the Sustainable Development Goals (SDGs), particularly SDGs 2, 7, 9, 12, 13, and 17”.

21

The Conclusions section should be further developed. Could you expand and strengthen this section?

We appreciate the valuable suggestion. The Conclusions section has been revised and expanded to strengthen the study's overall contribution. Specifically, we have improved the articulation between the research gap, the proposed framework, and its theoretical and practical implications.

Moreover, the revised section now more clearly emphasizes the framework's role as an enabler of Circular Economy implementation in the food industry, highlighting its contribution beyond descriptive analysis. We also reinforced the discussion on contributions to sustainability, clarifying that the study supports implementation pathways rather than directly measuring performance.

Furthermore, the conclusions now more explicitly address the connection between the proposed pillars and biorefinery systems, as well as the implications for future research. All changes have been incorporated into the revised manuscript. The new additions are as follows:

“This study aimed to propose strategic pillars to guide the adoption of the CE in the food industry, based on the systematization of structuring elements identified in scientific literature. Through a content analysis, thirty structuring elements of circularity were identified and organized into five pillars: valorization of waste and by-products, digitalization of the food chain, sustainable education and stakeholder engagement, strategic partnerships for circular businesses, and regenerative practices and renewable resources.

In doing so, the study directly addresses the research gap in the fragmentation between strategic CE approaches and their operational implementation, particularly in bio-refinery-based systems. The proposed pillars provide a structured conceptual framework that articulates circular practices within the specific context of the food industry, thereby offering a coherent pathway for transitioning from dispersed initiatives to integrated circular strategies.

In this way, the research question of how to structure strategic CE actions in the food industry was answered using evidence from the literature. The developed pillars also help fill the scientific gap by providing applicable frameworks that articulate circular practices within the specific context of the food sector.

The main scientific contribution of this study is the organization of a dispersed body of information on CE in the food industry. By integrating documented practices and proposing a functional categorization, this work deepens the field's theoretical foundation and supports further investigations into the application of circularity in food supply chains. From an applied perspective, the study offers an instructional tool for food industry companies seeking to align their operations with the principles of the CE. The proposed pillars provide practical guidelines that managers and professionals in the sector can operationalize to reduce waste, valorize residues, foster territorial partnerships, and incorporate regenerative technologies. In doing so, it contributes to the materialization of commitments aligned with the Sustainable Development Goals (SDGs), particularly SDGs 2, 7, 9, 12, 13, and 17. In this sense, it is important to emphasize that the sustainability value of this study does not directly measure environmental or social performance indicators, as it is limited to supporting the implementation of CE practices. By structuring and systematizing key elements, the study enables organizations to improve resource efficiency, reduce waste generation, and strengthen circular value chains, thereby achieving more effective sustainability outcomes in practice. This positions the study as an enabler of sustainability, rather than a direct measurement of sustainability performance.

Furthermore, this study illustrates the role of biorefinery systems as essential operational enablers for implementing CE principles in the food industry. Biorefineries provide the infrastructure required to convert diverse waste streams into high-value products, including functional ingredients, bio-based chemicals, and bioenergy, thereby linking food processing with biomass conversion pathways. The effectiveness of the proposed pillars is therefore strengthened when situated within integrated, multi-product biorefinery systems able to support circularity at scale.

For future studies, it is recommended to empirically validate the framework across different organizational contexts through case studies and sectoral analyses. Expanding the documentary base to include sustainability reports, technical standards, and institutional documents can strengthen the robustness of the proposed analytical structure. It is also suggested that the feasibility of applying the proposed pillars to small and medium-sized enterprises be investigated to enhance the proposal's scalability and applicability across diverse productive realities.

22

The manuscript is considered to have weak systematic review rigor and a largely descriptive synthesis with limited novelty, resulting in a superficial contribution that is methodologically insufficient for a high-impact journal. How can the rigor, depth, and originality of the study be strengthened?

We thank the reviewer for this critical and constructive assessment. We would like to clarify that the study is not intended to be a systematic review in the strict sense, but rather a qualitative, exploratory, and descriptive investigation grounded in content analysis. As stated in the Method section, “this research uses a qualitative, exploratory, and descriptive method grounded in content analysis”, positioning the study as a theory-building approach rather than a hypothesis-testing or purely systematic review study.

To ensure methodological rigor, the study adopts a structured analytical procedure. As described in the manuscript, “the assessment was conducted using a hybrid approach, combining a deductive methodology based on the 17 SDGs (…) with an inductive method focused on detecting emerging elements directly from the document collection”. This combination enhances analytical depth by integrating established theoretical categories with empirically grounded insights. In addition, the document selection process followed a transparent and traceable protocol, as indicated by “the corpus selection phase was carried out in accordance with the PRISMA protocol”, ensuring clarity and reproducibility in the construction of the analytical corpus.

Regarding the concern that the study is predominantly descriptive, we emphasize that the analysis moves beyond descriptive synthesis by systematically organizing and interpreting the identified elements. As detailed in the methodological steps, “the structuring elements were reorganized based on their thematic and functional affinities” and subsequently “consolidated into higher-order analytical dimensions”. This analytical process transforms dispersed evidence into structured categories, enabling interpretive depth rather than simple aggregation of findings.

In terms of originality, the main contribution of the study lies in developing a structured conceptual framework composed of strategic pillars. As presented in the Results and Discussion sections, the identified elements were “systematized into five strategic pillars”, which together form an integrated framework that connects circular practices, organizational strategies, and technological enablers. This represents a shift from fragmented, practice-oriented literature toward a coherent analytical model that supports decision-making and implementation in the food industry.

Furthermore, the study advances the literature by explicitly incorporating biorefinery systems as operational enablers of circularity. As highlighted in the manuscript, these systems provide the necessary infrastructure to convert heterogeneous biomass streams into high-value products, thereby bridging the gap between circular economy strategies and their large-scale industrial implementation.

To address the reviewer’s concerns, we have revised the manuscript to more clearly emphasize: the qualitative and theory-building nature of the study; the rigour of the hybrid analytical approach; the interpretive process underlying the categorization of elements; and the originality of the proposed framework and its integration with biorefinery systems. These revisions strengthen the clarity, depth, and positioning of the study within the literature.

23

Although the PRISMA framework is referenced, the screening and quality assessment process is not described in sufficient detail. Could you clarify:

• How study quality was evaluated?
• How inclusion and exclusion decisions were made beyond basic criteria?
• Whether bias assessment was conducted?
• Why quality-based exclusions were or were not applied?

We appreciate the reviewer’s insightful comment regarding the level of detail in the screening and quality assessment process. In response, we have substantially clarified and strengthened the methodological description in the revised manuscript.

First, the study selection process followed the PRISMA 2020 guidelines, and the corresponding flow diagram has been included to ensure transparency in the identification, screening, eligibility, and inclusion stages.

Regarding inclusion and exclusion decisions, beyond the initial criteria (i.e., English-language articles and reviews published between 2019 and 2024 and indexed in Scopus), a second-stage screening was conducted based on alignment with the research objective. Specifically, studies were excluded when they:

- did not focus directly on the food industry context;

- addressed CE only partially or peripherally, without contributing substantively to the analytical objective; or

- presented highly specific technical or laboratory-oriented approaches with limited relevance to the construction of broader strategic pillars.

These criteria are now explicitly reported in both the Method section and the PRISMA flow diagram.

Regarding quality assessment, this study employs a qualitative content analysis to identify, systematize, and synthesize recurring conceptual elements in the literature. Therefore, rather than applying a formal scoring system or excluding studies based on methodological quality thresholds, the analysis prioritized the conceptual relevance and contribution of each study to the development of structuring elements and strategic pillars.

Regarding bias assessment, a formal risk-of-bias evaluation (e.g., as used in clinical or quantitative meta-analyses) was not applied, as it is not fully compatible with the interpretative and exploratory nature of this research. However, bias was mitigated through:

- the use of transparent and reproducible selection criteria;

- the inclusion of highly cited and peer-reviewed studies; and

- the systematic coding and cross-comparison of elements across the selected literature corpus.

Finally, quality-based exclusions were not applied as a standalone criterion because the study's objective was not to evaluate the methodological robustness of individual studies, but rather to extract and organize recurring and transferable elements of CE practices in the food industry. Excluding studies solely based on methodological design could limit the diversity of perspectives necessary for building a comprehensive and integrative framework.

These clarifications have been incorporated into the revised manuscript to improve methodological transparency and rigor.

24

The content analysis mainly summarizes and categorizes extracted elements without deeper analytical synthesis. Could you provide:

• Stronger comparison across studies
• Assessment of evidence strength
• Exploration of contrasting findings
• Evaluation of the relative importance or empirical support of the identified structuring elements

We appreciate the reviewer’s insightful comment, which significantly contributed to strengthening the analytical depth of the manuscript.

In the revised version, the content analysis has been expanded beyond descriptive categorization to incorporate additional layers of comparison, interpretation, and synthesis.

First, to strengthen comparisons across studies, the analysis was refined to explicitly identify patterns of convergence and divergence in how CE practices are addressed within the food industry. The structuring elements were systematically compared across the selected studies based on their recurrence, thematic alignment, and functional roles, enabling a more integrative interpretation of the literature.

Second, an assessment of evidence strength was incorporated by considering both the frequency of occurrence and the consistency with which each structuring element appears across different studies and application contexts. Elements identified across several studies and diverse settings were interpreted as having stronger empirical support.

Third, the manuscript now includes a more explicit exploration of contrasting findings. While several studies emphasize technological and bioindustrial solutions—such as biorefineries, waste valorization, and digital traceability—as key enablers of circularity, others highlight structural and contextual challenges, including economic constraints, regulatory limitations, and supply chain complexity. These contrasting perspectives were incorporated into the analysis to reflect the multidimensional nature of CE implementation in the food sector.

Finally, regarding the relative importance of the structuring elements, the analysis was refined to differentiate them based on their recurrence, analytical relevance, and functional role within the proposed pillars. This allowed the identification of more central elements—those consistently observed across multiple studies—as well as complementary elements that are more context-dependent. This distinction enhances the interpretative robustness of the proposed framework.

These improvements were incorporated primarily in the Results and Discussion section, where the pillars are now presented not only as categorizations, but as analytically grounded constructs derived from a comparative and interpretative synthesis of the literature. The additions are highlighted in green:

5.1. Pillar 1 - Valorization of Waste and By-products

Valorizing waste and by-products is one of the most consistent strategies for operationalizing CE in the food industry. This pillar encompasses organizational practices aimed at reusing materials throughout the production chain, through the reinsertion of waste as productive inputs, the replacement of conventional materials, the setting of environmental goals, and the structuring of internal innovation mechanisms. The structuring elements of this pillar have been organized into four areas of action. In the selected articles, there is significant evidence highlighting the important role of waste valorization as a sine qua non condition for the circular transition, especially regarding resource efficiency and value generation. This evidence is emphasized by valorizing biomass and recovering resources biologically, which constitutes key strategies in circular food systems [42,77]. However, it is stressed that differences in the level of technological sophistication and scalability of solutions may vary from laboratory extraction processes to bio-based systems on an industrial scale. [37,80].

The area of productive and functional revaluation of by-products covers practices for transforming food waste into functional ingredients, biomaterials, and industrial inputs (#E2, #E19, #E20, #E25, #E29). The elements analyzed demonstrate, for example, the formulation of ingredients from fibers, legume proteins, and antioxidant compounds extracted from plant waste. Also discussed are processes for converting waste using insects as biotechnological vectors, and technologies that use green solvents to extract natural pigments, reducing dependence on synthetic inputs and adding value to previously discarded waste [37,42,82].

The focus on innovation in sustainable packaging includes the use of biodegradable, recyclable, and compostable materials in the food supply chain (#E6, #E16). It has been found that replacing conventional materials with bioplastics, such as polylactic acid (PLA), reduces plastic waste, promotes market differentiation, and meets the growing demand for environmentally responsible products [73]. In contrast to value-added technologies, packaging innovations tend to be more directly linked to market dynamics and consumer perceptions, playing a complementary role in the circular transition [43,73].

The monitoring and operational efficiency axis includes setting environmental goals, using performance indicators, and adopting tools for waste and by-product control (#E8, #E24). The materials analyzed converge on the application of sensors and digital management systems based on KPIs, aimed at the traceability of by-products and operational transparency. These mechanisms reinforce organizations' responsibility and the integration of sustainability into decision-making [43,67]. When these two elements are combined, they can boost the effectiveness and scalability of value-added strategies, highlighting the importance of monitoring and performance measurement tools in circular economy systems [61].

The internal structuring axis for R&D and by-product management encompasses actions to organize committees, internal programs, and operational routines to identify and value waste (#E1, #E22). There have been cases in which waste, such as peels, seeds, and inedible fractions, has been systematically analyzed to develop new products. In addition, initiatives include the collection and transformation of inedible waste—such as feathers, blood, and slaughter waste—into inputs for non-food applications, thereby converting environmental liabilities into alternative revenue streams [42,89]. These elements are recurrent in the literature, reinforcing their relevance in the analysis of this pillar [41,78].

Beyond specific technologies, the valorization of waste and by-products in the food industry constitutes a strategic change in how residual biomass is perceived and managed. Instead of being treated as inevitable losses or disposal problems, by-products are increasingly gaining space as secondary resources, as they can generate new economic, environmental, and social value. This perspective promotes reconfiguring food production systems towards integrated value chains, in which waste is systematically reintegrated into production cycles. Therefore, the transition from isolated, dispersed waste-handling methods to systemic valorization pathways requires industrial solutions that can operate at scale and accommodate the inherent heterogeneity of food-derived biomass flows [90–92].

From a bioindustrial perspective, the valorization of waste and by-products becomes feasible when supported by integrated biorefinery systems that handle heterogeneous biomass streams and convert them into a range of high-value products. In this context, biochemical biorefineries play a central role by enabling the fractionation of lignocellulosic and protein-rich residues through a sequence of unit operations, including pretreatment, enzymatic hydrolysis, fermentation, and downstream purification. These processes allow the recovery of functional ingredients, bioactive compounds, and bio-derived intermediates that would otherwise remain underutilized. Complementarily, thermochemical pathways—such as pyrolysis and gasification—offer viable routes for converting more recalcitrant fractions into bioenergy and platform chemicals, therewith reinforcing cascading use strategies within circular systems [93–95].

The pragmatic implementation of these valorization pathways increasingly depends on digital technologies embedded at the process level. High-tech sensors, Internet of Things (IoT) infrastructure, and data-driven models can support immediate monitoring of fermentation dynamics, optimize extraction yields, and anticipate maintenance needs in bioprocessing units. By improving process reliability and operational reliability, these tools improve economic performance and asset efficiency. In parallel, the recovery of nutrients through anaerobic digestion and wastewater treatment systems enables nitrogen, phosphorus, and organic matter to be reintroduced into agricultural cycles, strengthening the regenerative dimension of waste valorization strategies [20,96].

Although these biorefinery-based routes show notable promise, many remain at intermediate Technology Readiness Levels (TRLs). Challenges related to feedstock heterogeneity, process scale-up, and general economic viability continue to limit broader industrial deployment. For this reason, the combined application of techno-economic analysis and life cycle assessment remains necessary for assessing trade-offs and demonstrating the sustained viability of multi-product biorefineries, particularly those aiming to simultaneously produce nutraceuticals, biochemicals, and bioenergy from food waste streams [96,97].

5.2 Pillar 2 - Digitization of the Food Chain

         The digitalization of the food chain has played a strategic role in enabling the CE by allowing real-time monitoring of resources, strengthening traceability, and creating more intelligent, more sustainable production environments. The structuring elements of this pillar focus on the application of emerging technologies for process optimization, transparency enhancement, and the connection between operational efficiency and social responsibility. Grouped into two thematic axes, these elements support a digitally oriented approach to circularity. In the studies analyzed, strong convergence is observed regarding the role of digital technologies as infrastructures that facilitate circularity, particularly by improving the visibility of material flows and supporting decision-making processes.

The axis of automation and intelligent resource monitoring encompasses practices that use advanced technologies to measure, control, and optimize the consumption of critical inputs throughout the production chain (#E7, #E9). These solutions include sensors, integrated systems, and automation resources that enable the real-time tracking of environmental performance indicators, promoting continuous adjustments and efficiency gains. Furthermore, the use of Industry 4.0 technologies contributes to more accurate management of byproducts and waste, enabling leaner, more connected production flows. This axis also integrates the adoption of business models that combine technological innovation with Corporate Social Responsibility practices, focusing on material reuse and the promotion of workers’ and community well-being [67]. These elements recur across many studies, indicating their empirical relevance and reinforcing their role as important facilitators of circular practices in digitally supported production systems.

The axis of traceability and digital transparency refers to the digitalization of production and logistics processes, incorporating technologies such as blockchain, IoT, and augmented reality to ensure the traceability of food products (#E12). These tools enable the accurate recording of product origins, logistics routes, and environmental impacts, facilitating consumer access to reliable information and strengthening trust across the value chain. In addition to enhancing food safety, digitalization at this level allows companies to clearly communicate their environmental commitments and increase accountability for the life cycles of their products [43,73].

On the bioindustrial side, digitalization of the food chain is a strategic means to support CE practice and contributes to the operational complexities associated with biorefinery-based systems. All integrated biorefineries depend on seamless coordination among heterogeneous biomass streams, diverse conversion routes, and variable process conditions. Digital technologies here function as enablers or infrastructures that enhance the visibility of material flows, energy consumption, and process performance in real time, thus enabling circular practices to be developed and operated much more accurately and reliably [98,99].

In biorefinery settings, automation and intelligent resource monitoring become vital to the sustainability of fermentation, enzymatic conversion, separation, and energy recovery activities in highly regulated environments. The sensors, integrated control systems, and data-driven monitoring tools could help fine-tune temperature, pH, residence time, and substrate utilization, minimize losses, and optimize biomass valorization routes. Through greater control over by-product and waste streams, digitalization reinforces the link between food processing and downstream biorefinery by embedding leaner, more connected circular production flows [100,101].

Similarly, digital traceability and transparency tools are gaining importance beyond consumer applications, enabling governance and accountability across bio-based value chains. Digitalized systems of traceability can track the source, processing route, and environmental performance of biomass in a biorefinery network of suppliers and support coordination among food producers, biorefineries, and other partners [102,103].

5.3 Pillar 3 - Sustainable Education and Stakeholder Engagement

The transition toward circular systems in the food industry requires technological and operational innovations accompanied by cultural and behavioural changes. The engagement of consumers, employees, and other actors in the chain emerges from effective communication strategies, educational programs, and transparent channels for dialogue. This pillar organizes the structuring elements into two complementary thematic axes: education for circularity and informational engagement. It is possible to verify, in the delimited studies, that behavioural change and stakeholder awareness act as fundamental bridges for the transition of the EC, since technology, by itself, does not affect consumer perception and organizational culture [44,64]. However, there are significant variations in the depth and scope of engagement strategies, ranging from informative approaches to more participatory and transformative initiatives.

The axis of education and awareness for responsible consumption encompasses actions that educate consumers about the impacts of waste, the benefits of circular products, and the importance of sufficiency as a guiding principle in decision-making (#E3, #E5, #E15). Strategies such as educational campaigns, environmental labelling, and the inclusion of sustainability messages on packaging have been used to promote food choices aligned with circularity. These practices are particularly effective when linked to health and well-being attributes, as demonstrated by studies on the acceptance of functional foods produced from by-products [64,73]. These elements appear in many studies, standing out as drivers of consumer alignment with circular practices, particularly when associated with perceived benefits for health and the environment [46].

The axis of technological communication and digital engagement involves providing accessible information about production processes, highlighting the use of by-products and the environmental impacts associated with food (#E21, #E30). Digital technologies such as social media, QR codes, and interactive platforms have proven to be practical tools for bringing consumers closer to sustainable organizational practices, fostering trust and active engagement. In addition to countering greenwashing, this axis encourages dialogue with society and strengthens the institutional positioning of companies committed to circularity [39,43]. While educational approaches focus on behavioural change, digital engagement strategies tend to emphasize transparency, interaction, and accessibility to information, thereby complementing trust-building and stakeholder involvement rather than directly influencing consumption patterns [39].

Educational and stakeholder engagement are essential for the social and institutional acceptance of bioindustrial circular solutions. For integrated biorefineries, unconventional feedstocks, such as food waste, by-products, or wastewater-derived biomass, are often used, which may be met with skepticism from consumers and other actors if they are not well communicated. Education projects that inform consumers about biorefinery processes, product safety, and environmental benefits also reduce perceived risk and increase the acceptance of bio-based products. Transparent communication of the origin, processing routes, and end uses of biomass streams also promotes coordination among food producers, biorefineries, regulators, and local communities. By combining knowledge sharing within a participatory context, this pillar reinforces the socio-technical foundations needed to scale biorefinery-driven CE models in the food sector [104–106].

5.4 Pillar 4 - Strategic Partnerships for Circular Businesses

    The transition toward circular production models in the food industry requires coordination among multiple actors. Strategic partnerships enable the sharing of technical knowledge, the joint development of sustainable solutions, and the territorial integration of circular practices. This pillar consists of structuring elements that guide the formation of collaborative arrangements among companies, research centers, and local suppliers, organized into two principal axes. In the studies analyzed, the role of interorganizational collaboration as a structural condition for circularity is evident, especially in complex, resource-intensive sectors such as the food industry. From this perspective, circular transitions do not depend solely on internal capabilities; coordinated actions among supply chain actors are also necessary [63,68].

The axis of technological and institutional partnerships encompasses collaborations with biorefineries, universities, R&D centers, and other organizations within the innovation ecosystem focused on by-product reuse and energy conversion from waste (#E11, #E18). The initiatives described range from anaerobic digestion in local biorefineries for renewable energy production to the formation of interorganizational collaboration networks to finance, test, and scale circular solutions. Such arrangements strengthen the technical capacity and resilience of organizations while generating positive externalities for both the territory and the institutional environment in which they operate [51,66].

The axis of territorial reconfiguration of the supply chain focuses on building shorter, more resilient, and sustainable supply chains by prioritizing local suppliers and reterritorializing production (#E23, #E27). The proximity-based logic seeks to minimize logistical emissions, reduce transportation costs, and foster local economies. Moreover, it reinforces the synergy between environmental sustainability and regional development, contributing to more autonomous and less vulnerable food systems [51,81].

From a bioindustrial perspective, strategic partnerships play a decisive role in enabling the deployment of integrated and multi-product biorefineries, which typically go beyond the technical, financial, and organizational capacity of individual firms. The implementation of these systems depends on coordinated investments, shared access to biomass streams, and effective alignment among food producers, biorefineries, technology providers, and public institutions. In this context, territorially based partnerships facilitate the aggregation of heterogeneous feedstocks, improve logistical efficiency, and support the alignment of regulatory and sustainability objectives [106–108].

5.5 Pillar 5 - Regenerative Practices and Renewable Resources

The incorporation of regenerative practices and the strategic use of renewable resources are essential to reversing environmental impacts and building food systems that are more resilient, biodiverse, and self-sustaining. This pillar is structured around structuring elements aimed at regenerating productive ecosystems, reducing chemical inputs, and converting waste into energy and biomass, organized into two interdependent axes. The analyzed studies that comprised this pillar address the growing importance of regenerative approaches to improve circular systems, especially in light of the environmental limitations identified in efficiency-based models. In this sense, it is necessary to go beyond waste reduction, seeking the restoration of ecological functions and the regeneration of resources in the long term [51,66].

The axis of ecological recovery and systemic efficiency brings together agricultural practices that promote soil health, the sustainable use of natural resources, and the redesign of production in line with degrowth principles (#E10, #E13, #E26). These actions include replacing chemical inputs with agroecological strategies, fostering functional biodiversity, and using statistical models to address uncertainties in demand and resource allocation. In addition to increasing the efficiency of material flows, these approaches also challenge the paradigm of unlimited growth and guide organizations toward achieving a balance between environmental performance and value creation over time [43,51].

The axis of bioenergy and regenerative waste valorization focuses on initiatives that transform waste into renewable energy, biomass, and productive inputs through advanced technologies (#E4, #E14, #E17, #E28). Among these initiatives, automated composting, pyrolysis for biofuel production, and the use of waste-fed microalgae to generate lipids, carbohydrates, and functional biomass stand out. Algae cultivation is also highlighted as a strategy for carbon sequestration and for reducing pressure on arable land. These practices, in addition to being regenerative, enhance circularity by linking energy solutions with routes for by-product reuse [66,109].

From the perspective of bioindustrial, regenerative activities and the exploitation of renewable resources are closely associated with the development of integrated biorefinery systems, which strive to close the loops of materials, energy, and nutrients. Emerging technologies like anaerobic digestion, thermochemical conversion, and algae-based platforms enable the recovery of energy and nutrients from organic residues, supporting agricultural regeneration and industrial sustainability. Integration of bioenergy and biomass valorization along these routes into circular food systems can reduce dependence on fossil fuels, improve overall system resilience, and foster synergies among food production, energy generation, and ecosystem restoration [101,106].

25

The classification of circular economy practices according to SDGs appears to rely primarily on author interpretation. Could you clarify:

• Whether multiple coders were involved
• How disagreements were resolved
• How overlaps across SDGs were handled
• Whether any validation procedures were applied to the categorization

We appreciate the reviewer’s valuable comment regarding the categorization of circular economy practices in relation to the Sustainable Development Goals (SDGs).

We would like to clarify that the association between the identified structuring elements and specific SDGs was adopted as a supporting analytical procedure, rather than as the central objective of the study. The primary aim of the research is to propose and structure strategic pillars for the implementation of Circular Economy practices in the food industry. In this context, the SDGs were used as a guiding framework to contextualize the broader sustainability relevance of these elements.

Regarding the coding procedure, the classification was conducted through an interpretative content analysis process, following a hybrid approach that combines deductive categories (based on the SDGs) with inductive identification of elements emerging from the literature. Given the conceptual and exploratory nature of the study, the coding was performed by the authors, with continuous cross-checking and iterative refinement of the categorizations to ensure internal consistency and conceptual alignment.

Disagreements in classification were addressed through discussion and consensus among the authors, prioritizing theoretical coherence and alignment with the core meaning of each SDG. This interpretative alignment process is consistent with qualitative content analysis approaches, particularly in exploratory studies.

With respect to overlaps across SDGs, we acknowledge that several structuring elements could be associated with multiple goals. However, in order to maintain analytical clarity and avoid excessive fragmentation, each element was linked to the SDG with which it presented the strongest conceptual alignment. This decision was made to preserve the parsimony and operational usefulness of the analytical framework.

Finally, although no formal external validation procedure was applied, the robustness of the categorization is supported by its grounding in well-established SDG definitions and its consistency with patterns observed across the analyzed studies. The SDG mapping is therefore presented as a complementary interpretative layer, intended to enhance the understanding of the sustainability implications of the proposed framework, rather than as a definitive or exhaustive classification. To correct this aspect in the manuscript, we made the following insertion:

“The association between the identified structuring elements and the SDGs was carried out as a complementary analytical step, aiming to contextualize the relevance of the findings for sustainability. Given the exploratory nature of the study, each element was linked to the SDG with which it showed the greatest conceptual alignment to preserve clarity and avoid overly overlapping interpretations. This procedure was performed through iterative interpretation and cross-validation among the authors, ensuring internal consistency and theoretical alignment. The link between the structuring elements and the SDGs is therefore interpreted as a conceptual alignment rather than a direct measure of impact. In this sense, the potential contributions of CE practices to specific SDGs are considered con-text-dependent and may involve trade-offs, depending on technological, organizational, and regulatory conditions.”.

26

The proposed circular economy pillars and framework are derived solely from literature grouping, without empirical testing, case application, or performance evaluation. Could you provide evidence of their practical relevance or effectiveness, or clarify their conceptual nature?

We appreciate the reviewer’s important observation regarding the conceptual nature of the proposed framework.

We would like to clarify that the primary objective of this study is to develop a conceptual and integrative framework, grounded in a systematic and structured synthesis of the literature, rather than to empirically test its application. The proposed pillars are derived from the identification, comparison, and interpretation of recurrent structuring elements observed across multiple studies on Circular Economy practices in the food industry.

Although the framework is not empirically validated within this study, its practical relevance is supported by the fact that the identified elements are drawn from empirical and applied research contexts reported in the literature. These elements reflect real-world practices—such as waste valorization, digital traceability and reverse logistics.

In this sense, the framework does not propose abstract constructs detached from practice, but rather organizes and integrates dispersed evidence into a structured and operational model. This allows practitioners to better understand how different circular strategies can be articulated within food systems, thereby enhancing their applicability.

Furthermore, the framework is presented with an explicit applied orientation, as the proposed pillars are linked to actionable pathways—such as resource efficiency, biomass valorization, stakeholder engagement, and supply chain integration—providing guidance for decision-making and strategic planning in food industry contexts.

We acknowledge that empirical validation through case studies, performance measurement, or quantitative assessment would further strengthen the framework. Accordingly, this represents a promising avenue for future research, particularly in testing the applicability and effectiveness of the proposed pillars across different organizational and geographical contexts.

27

Although prior systematic reviews on circular economy in the agri-food sector are cited, it is not clear how the proposed framework advances beyond existing studies. Could you clarify the manuscript’s distinct conceptual contribution?

We appreciate the reviewer’s important comment regarding the distinct conceptual contribution of the manuscript.

While prior studies have explored Circular Economy (CE) practices in the agri-food sector, the literature remains largely fragmented, typically addressing isolated dimensions such as waste valorization, supply chain management, or specific technological solutions. To the best of our knowledge, no previous study has systematically integrated these dispersed practices into a unified and structured framework tailored to the food industry.

The main contribution of this manuscript lies in the organization of a dispersed body of knowledge into a functional and coherent structure, through the identification and categorization of 30 recurrent elements into five strategic pillars. This approach advances beyond existing reviews by providing a multi-dimensional and integrative perspective, rather than a thematic or sector-specific analysis.

From a theoretical standpoint, the study contributes by deepening the conceptual foundation of Circular Economy in the food industry, articulating relationships between technological, organizational, and socio-environmental dimensions that are often treated separately in the literature. This integrative perspective supports future research by offering a structured basis for the analysis and operationalization of circular practices in food supply chains.

From an applied perspective, the proposed framework functions as an instructional and decision-support tool for practitioners in the food industry, enabling organizations to align their operations with CE principles in a more structured and actionable manner. By translating documented practices into a systematized model, the study facilitates the practical understanding and implementation of circular strategies.

Therefore, the contribution of this work lies not in introducing entirely new practices, but in reorganizing existing knowledge into an original, integrative, and operational framework, addressing a gap in the literature related to the lack of structured models for guiding CE implementation in the food sector. The following is the portion of the text included in the manuscript to reinforce this reasoning:

28

The manuscript frequently links circular economy practices to multiple SDGs without providing evidence regarding:

• The magnitude of contributions
• Contextual conditions
• Potential trade-offs

Could these claims be substantiated or better qualified?

The linkage between Circular Economy practices and the SDGs is interpreted in this study as a conceptual alignment, rather than a direct measurement of impact, given the qualitative and exploratory nature of the analysis.

The linkage between Circular Economy practices and the SDGs is interpreted in this study as a conceptual alignment, rather than a direct measurement of impact, given the qualitative and exploratory nature of the analysis.

We appreciate the reviewer’s important observation regarding the linkage between Circular Economy (CE) practices and the Sustainable Development Goals (SDGs).

We acknowledge that the manuscript does not aim to quantitatively measure or empirically demonstrate the magnitude of contributions of CE practices to specific SDGs. Instead, the association is intended as a qualitative and interpretative alignment, based on the conceptual correspondence between the identified structuring elements and the objectives defined within the SDG framework.

In the revised version, we have clarified this positioning to avoid overinterpretation. The references to SDGs are now presented as indicative of potential contributions, rather than direct or measurable impacts. This distinction is particularly relevant given the exploratory nature of the study and the diversity of contexts in which CE practices are implemented.

Furthermore, the manuscript has been refined to better acknowledge that the relationship between CE practices and SDGs is context-dependent, varying according to organizational characteristics, technological maturity, regulatory environments, and supply chain configurations. As such, the potential benefits of circular strategies may differ significantly across settings.

We also incorporated a more balanced discussion by recognizing that CE practices may involve trade-offs and implementation challenges, including economic feasibility constraints, regulatory limitations, and operational complexities. These aspects were integrated into the discussion to avoid an overly optimistic interpretation of circular transitions.

Therefore, the SDG linkage in this study should be interpreted as a conceptual mapping that highlights alignment with sustainability objectives, rather than as a direct assessment of performance or impact magnitude. The written portion developed in the manuscript is highlighted in question 25.

29

The paper states that circular economy actions directly support several SDGs but does not present empirical evidence demonstrating these outcomes. Could empirical support or a clearer justification be provided?

We appreciate the reviewer's valuable comment on the relationship between Circular Economy (CE) practices and the Sustainable Development Goals (SDGs).

We acknowledge that this study does not aim to measure or empirically demonstrate the direct impact of CE actions on SDG outcomes. Instead, the manuscript adopts a qualitative, literature-based approach, in which the relationship between CE practices and the SDGs is interpreted as a conceptual alignment grounded in previous research, rather than a direct causal validation.

In the revised version, we refined the wording throughout the manuscript to avoid statements that could be interpreted as implying direct or quantified support. The relationship with the SDGs is now presented consistently in terms of potential contributions and theoretical alignment, based on the sustainability dimensions addressed in the analyzed studies.

Furthermore, the justification for this alignment is supported by the fact that the identified structuring elements—such as waste valorization, resource efficiency, renewable inputs, stakeholder engagement, and circular supply chains—are widely discussed in the literature as mechanisms associated with sustainability outcomes consistent with the SDGs.

We also clarify in the Methods section that this association serves as an analytical and contextual mapping, and not as an empirical assessment of the magnitude of the impact. This positioning reflects the exploratory nature of the study and ensures that the interpretation remains consistent with the methodological approach adopted.

Taking advantage of this suggestion, we include it as a suggestion for future research, which could be based on this framework through empirical validations, including performance measurement, case study analysis, or quantitative assessment of the contributions of the circular economy to specific SDGs. The excerpt from the conclusion follows below:

For future studies, it is recommended to empirically validate the framework across different organizational contexts through case studies and sectoral analyses. In particular, future research may examine the magnitude of CE practices' contributions to specific sustainability outcomes, as well as the contextual conditions and potential trade-offs associated with their implementation. Expanding the documentary base to include sustainability reports, technical standards, and institutional documents can strengthen the robustness of the proposed analytical structure. It is also suggested that the feasibility of applying the proposed pillars to small and medium-sized enterprises be investigated to enhance the proposal's scalability and applicability across diverse productive realities.

30

The review emphasizes opportunities and benefits of circular economy practices while giving limited attention to barriers, costs, failures, or institutional challenges. Could the manuscript incorporate discussion of:

• Economic feasibility
• Regulatory constraints
• Adoption resistance
• Implementation difficulties

to avoid an overly optimistic synthesis?

We appreciate the reviewer’s valuable comment regarding the need to provide a more balanced perspective on Circular Economy (CE) practices in the food sector.

In the revised version, the manuscript has been refined to incorporate a more critical discussion of the challenges associated with CE implementation. While the initial focus emphasized opportunities and enabling mechanisms, we acknowledge that the transition toward circular systems is conditioned by multiple constraints that affect feasibility and scalability.

Specifically, we have included a discussion addressing:

·         Economic feasibility, particularly the low market value of certain waste streams and the high costs associated with reverse logistics and processing infrastructure;

·         Regulatory constraints, including food safety regulations and policy misalignment that may limit the use of certain by-products or circular practices;

·         Adoption resistance, related to organizational inertia, lack of technical capabilities, and cultural barriers within firms and supply chains;

·         Implementation difficulties, especially those associated with coordinating heterogeneous biomass streams, integrating biorefinery systems, and aligning stakeholders across complex value chains.

These aspects were primarily incorporated into the Introduction and Discussion sections to provide a more nuanced and realistic interpretation of CE implementation in the food industry. As a result, the manuscript now presents a more balanced synthesis that recognizes both the potential and the limitations of circular strategies.

“In addition to financial costs, regulatory constraints, a lack of technical capabilities, and the complexity of coordinating stakeholders along supply chains, these factors can also limit the advancement of the CE in the food industry. These challenges highlight that the transition to circular systems involves aspects beyond technology, including institutional and organizational processes, and requires alignment with various internal and external stakeholders [20–23]”.

5

Please strengthen the inclusion of recent studies (2025), particularly in the Introduction or Discussion, even if they are not part of the original dataset due to the review scope.

Thank you for this valuable suggestion.

In response, we have incorporated recent studies published in 2025 and 2026 to update and strengthen the manuscript. These additions were included across different sections of the paper in order to improve alignment with the most recent advances in circular economy, food systems, digitalization, and biorefinery-based approaches.

Specifically, the following recent references were added to the revised version of the manuscript: Rizwan et al. (2025), Zhao et al. (2025), Ragini et al. (2025), Chen et al. (2026), and Tudor et al. (2026). These studies were used to reinforce key discussions related to stakeholder engagement, Industry 4.0 applications, circular supply chains, regenerative practices, and integrated biorefinery systems.

In addition, the reference base demonstrates a strong emphasis on recent literature, with approximately 48% of the references corresponding to studies published within the last five years (2021–2026). This ensures that the manuscript reflects current developments while remaining grounded in well-established theoretical foundations.

Overall, this balance between recent and foundational studies enhances both the contemporaneity and the robustness of the research.

6

Although the search terms are presented, the manuscript should include the full Scopus search string (as used in the Advanced Search query) to ensure full replicability of the study.

Thank you for this important observation. In response, we have revised and clearly organized the Scopus advanced search string to improve transparency and ensure full replicability of the study.

Specifically, the query was reformulated to eliminate redundancies, correct logical structuring, and ensure proper grouping of search terms and filters. The revised search string is now explicitly presented in the Methodology section, clearly separating the Circular Economy and food-related terms, as well as the applied filters (publication year, document type, and language).

This improvement enhances the methodological clarity and allows future researchers to accurately reproduce the data collection process.

7

Please improve the readability of Table 1, which is currently difficult to interpret.

Thank you for this helpful comment. In response, we have substantially improved the readability and clarity of Table 1 by restructuring its format.

Specifically, we redesigned the table to present a simplified and synthesized view of the structuring elements, focusing on their associated SDGs and frequency of occurrence. This new layout reduces visual complexity and makes it easier to interpret and compare elements.

To preserve transparency and methodological rigour, the full detailed matrix—showing the mapping between structuring elements and individual articles—has been retained and relocated to Appendix A (Table A2).

These changes significantly enhance readability while maintaining the completeness and traceability of the analysis.