Sustainable Valorization of Tequila Industry Vinasse: A Patent Review on Bioeconomy-Driven Technologies

Abstract

The tequila industry generates significant quantities of vinasse, a highly polluting byproduct that poses serious environmental challenges. Addressing this issue requires innovative solutions that align with the principles of bioeconomy, transforming waste into valuable resources. This article provides a comprehensive review of 688 scientific articles and 315 patent documents related to vinasse valorization technologies, retrieved from the Scopus and Espacenet databases. The review identifies key types of vinasse valorization, including bioethanol, biofertilizers, biogas, animal feed, biodiesel, and phenolic compounds, and evaluates trends, technical advances, and commercialization pathways. The findings highlight the feasibility of integrating these technologies within the tequila production process, promoting environmental sustainability and economic efficiency, and mention the current limitations of vinasse-based innovations. This study aims to guide researchers, industry stakeholders, and policymakers in developing strategies to harness the full potential of vinasse, contributing to a more sustainable and circular economy.

1. Introduction

The tequila industry has grown into a globally recognized sector known for producing the iconic beverage distilled from the blue agave plant. Tequila, once primarily produced and consumed within Mexico (recognizing the value of the “liquid gold” from the blue agave, the Mexican government took initiatives to protect tequila as early as the 1970s; tequila became the country’s first appellation of origin in 1974, and in 1978, it was internationally registered for protection under the Lisbon Agreement for Protection of Appellations of Origin and their International Registration), is now a widely commercialized and highly demanded beverage across the world. In 2023 alone, the international demand for tequila reached 333,536,305 L, with the United States accounting for a staggering 94% of this consumption, making it the top consumer [1]. According to the Tequila Regulatory Council (CRT), between 2000 and 2023, tequila production in Mexico saw an impressive 120% increase. Notably, in 2008, it reached 312.1 million liters, and by 2022, it had more than doubled to 651.4 million liters [1]. This remarkable growth has positioned the tequila industry as one of the few that not only sustained but also expanded during the global COVID-19 pandemic [2]. Nevertheless, despite its economic importance and cultural relevance, the tequila industry faces considerable environmental challenges throughout its production stages, from agave cultivation to bottling [3], with vinasse being the primary polluting waste due to its volume and chemical makeup.

Vinasse is a liquid waste characterized by high organic content, including chemical oxygen demand (COD) (25–100 g/L), total solids (20/50 g/L), low pH (3.4–4.5), low concentrations of phenols (0.04–0.08 g/L) and salts (0.45–2.05 g/L), and a high Carbon-to-Nitrogen ratio (100/0.64) [4]. Its effects include decreased water clarity, reduced photosynthetic activity, and lower dissolved oxygen levels, which can lead to eutrophication, increased insect and vector populations, and subsequent disease outbreaks. These characteristics make vinasse the most significant environmental challenge in the tequila production process [5].

For every liter of tequila produced, between 10 and 12 L of vinasse is generated [6]. Based on this ratio, from 1995 to 2023, when the CRT reported tequila production data, the industry would have produced approximately 7838.7 million liters of tequila, resulting in an estimated average of 86.2257 billion liters of vinasse.

The tequila industry presents a compelling case study for the application of circular economy and bioeconomy principles due to its significant generation of byproducts and organic waste, particularly vinasse. As noted by Díaz-Vázquez et al. [7], small- and medium-sized producers often struggle to manage this residual waste effectively due to technical and financial limitations. Consequently, it is common for these producers to discharge untreated or partially treated vinasse directly into the environment, causing serious local environmental problems.

The shift towards a bioeconomy opens opportunities to transform this problematic waste into valuable resources. Integrating vinasse management into a circular framework involves creating and implementing sustainable processes to convert these wastes into valuable inputs for other industrial applications, such as phenolic compounds, animal feed, biofertilizers, bioethanol, biogas, and biodiesel, according on Nakar et al. [8], Alenman-Nava et al. [9], Kumar et al. [10], Teymennet-Ramírez et al. [11], and Ferral Pérez et al. [12].

A patent search plays a crucial role in identifying and understanding technologies applicable to this scheme. By reviewing patents, stakeholders can gain insights into the latest innovations and advancements in vinasse treatment and valorization. Patents provide detailed descriptions of novel processes and technologies, offering a wealth of technical information that can guide the development and implementation of sustainable practices.

Patents are among the earliest forms of intellectual property recognized in modern legal systems. By securing a patent, the inventor obtains exclusive rights to the invention, allowing them to prevent others from using, making, or selling it without authorization. In exchange, the patent holder must disclose comprehensive details of the invention in the published patent documents [13]. Consequently, they serve as valuable sources of information and often provide a concise history of technological advancements in their respective fields [14].

2. Materials and Methods

A patent search was carried out in December 2024 using the Espacenet international database, managed by the European Patent Office. This platform offers free access to inventions and technical developments from 105 countries, following the method outlined by Nascimento et al. [15]. The terms “vinasse” OR “distillery waste” OR “fermentation residue” AND International Patent Classifications (IPC), codes, and subcodes were applied to ensure that all documents pertinent to the search objective were considered (Figure 1). In addition, filters such as a time range of 2000–2024, document types granted and pending patent applications, field titles, and abstracts were applied. Patents were manually reviewed to remove duplicates. If a patent appeared under more than one IPC classification, it was included only once and categorized based on its primary objective.

Figure 1 presents a detailed overview of the relevant IPC codes and their associated subcodes related to various vinasse byproducts.

The Boolean operator (AND) was used to ensure that the term, IPC code, and dates were present in the documents evaluated. The term “patent document” includes both submitted and granted patents. The search resulted in a total of 357 patent documents. All patents were analyzed and selected whether the patent meets the criteria for any of the specified byproducts, by the following abstract content and technical feasibility (

Table 1. Criteria method for patent document selection.

Criterion	Inclusion	Exclusion
Patent content (abstract description)	- Explicit description of processes/products related to vinasse and its derivatives - Keywords like “vinasse”, “waste from distillation”, “fermentation residue” present - Clear pathway for converting vinasse into desired byproduct	- No mention of vinasse or related byproducts - Vague or unrelated technologies
Byproduct category	- Specific byproduct category is identified and addressed	- No clear byproduct category is identified
Vinasse use/transformation	- Clear description of how vinasse is used or transformed	- No description or insufficient explanation of vinasse’s role
Technical feasibility and depth	- Detailed explanation of the technical process with alignment to known vinasse applications	- Lack of technical detail or misalignment with known applications of vinasse
Patent quality	- High technical rigor, specific methods, and applicable practical use	- Vague, theoretical, or peripheral methods that lack clear practical application

):

A total of 315 patent documents were selected based on the outlined method. The relevant data from these documents were extracted and organized in Microsoft 365 Excel for subsequent analysis. The patents were examined by determining the filing years, countries of origin, applicants, and application areas. Visual representations were created using Lucid.app (https://lucid.app) Software and the Canva platform (https://www.canva.com).

In December 2024, scientific articles were identified through a search in the Scopus database using the terms “vinass*,” “by product,” and “treatment” within the years 1999 to 2024, focusing on titles, abstracts, and keywords. Filters such as the years 1999 to 2024, document types including articles and reviews, and the English language were applied. A total of 1230 articles were initially retrieved. After reviewing the presence or absence of references to agave vinasse or related terms, the connection of byproducts to agave vinasse, and the technical aspects or methodologies that confirmed or contradicted the relevance to agave vinasse and its processing, 688 documents were selected for further analysis. The data from these documents were exported into Microsoft 365 Excel for subsequent review. The articles were examined by identifying key attributes such as publication years, authors, countries of origin, and application areas. Visual representations were created using the Canva platform.

3. Results

3.1. Technological and Scientific Landscape Analysis: Temporal, Technical, and Geographical Perspectives

Historical Development of Research Publications

Early research on vinasse, dating back to 2002, focused on the chemical composition of vinasse and its potential as a substrate for biodegradation and bioethanol production. Research during this period was more theoretical, addressing the basic chemical and environmental properties of vinasse (Figure 2). There was an increasing awareness of the need to manage vinasse from ethanol plants and other industries. By 2005, studies’ attention shifted to anaerobic digestion methods to treat vinasse, identifying potential for methane production. These studies set the stage for future research on biogas from vinasse.

As shown in Figure 2, patent filings and scientific articles related to vinasse technologies began to rise and become more applied after 2010, reaching a notable peak between 2016 and 2020. Early developments focused on the treatment of vinasse for specific byproducts, especially in the context of biogas production and nutrient recovery. Padilha de Souza et al. [16] investigate the treatment of vinasse using a combination of vegetable tannin coagulation and photocatalysis. The results show that this combined process achieves an 80% reduction in COD and 87% in color, alongside a considerable reduction in toxicity, as tested with Artemia salina. The study concludes that this method is an effective and environmentally friendly way to treat vinasse, enabling its potential reuse in industrial processes.

Christofoletti et al. [17] focus on the environmental impacts of sugarcane vinasse and explore its potential uses and associated challenges. The paper addresses the problems related to the improper disposal of vinasse, such as the pollution of water bodies and soil, highlighting its high biochemical oxygen demand, which can lead to oxygen depletion in aquatic ecosystems. Moreover, vinasse’s impact on plant seed germination is discussed, noting that excessive concentrations can inhibit seed growth, although lower concentrations can have beneficial effects on some crops. The review emphasizes the need for more sustainable methods of vinasse disposal and suggests that new technologies for recycling and utilizing this byproduct could help mitigate its environmental impact.

Taina et al. [18] present a method for treating sugarcane vinasse using a two-stage anaerobic membrane bioreactor. By separating these stages, the method improves treatment efficiency by reducing harmful volatile fatty acids and enhancing the breakdown of organic matter. However, the study found that certain byproducts, such as soluble microbial products and extracellular polymeric substances, caused fouling in the system. Despite this, the method showed great potential for treating vinasse and recovering energy. Further optimization is needed to make it suitable for large-scale use.

Table 2. Key cited studies on vinasse byproduct valorization.

Title	Main Objective	Findings
Use of Anaerobic Co-digestion for Sugarcane Biorefinery Wastes [19]	Evaluate how different combinations of sugarcane byproducts affect methane production in anaerobic digestion	Optimal conditions for biogas were identified with good methane yields. Sugarcane bagasse fly ash enhanced biogas production.
Anaerobic Thermophilic Digestion of Cutting Oil Wastewater [20]	Investigate the effect of cutting oil wastewater (COW) when co-digested with vinasse in a thermophilic anaerobic reactor	Vinasse alone showed good biogas production, but COW reduced methane production and COD removal. Further research is needed for COW degradation.
Degradation of Wine Distillery Wastewaters Using Aerobic Treatment and Fenton’s Reagent [21]	Examine the combined effects of aerobic treatment and Fenton’s reagent on wine distillery wastewater	The aerobic treatment effectively degraded COD, biomass, and aromatic compounds. The use of Fenton’s reagent further degraded contaminants, and a kinetic model was developed to optimize the process.
Start-up Phase of Anaerobic Co-digestion from Food Waste and Vinasse [22]	Investigate the start-up phase of anaerobic co-digestion with food waste and vinasse to optimize hydrogen and methane production	The study demonstrated significant reduction in total solids, peak hydrogen production at 76.5%, and high methane production with over 300 mL of biogas per g of volatile solids.
Pretreatment of Vinasse Using Trametes Versicolor and UASB Reactor [23]	Assess the effectiveness of Trametes versicolor for pretreating vinasse in a fluidized bed bioreactor coupled with an Upflow Anaerobic Sludge Blanket reactor	The pretreatment removed phenolic compounds and COD, improving methane production. The system showed potential for industrial application.

shows the main articles that investigates vinasse products

Later, a pivotal trend of vinasse as a source of phenolic compounds was found. Molina-Cortés et al. [23] looked at the antioxidant properties of molasses and vinasses. The researchers found that vinasses had much higher antioxidant levels and more phenolic compounds than molasses, highlighting the potential of vinasses as a source of natural antioxidant agents, which could have applications in the pharmaceutical industry. Also, Silva, V. et al. [24] explored how a heat-loving bacterium, Thermoanaerobacterium calidifontis VCS1, can turn xylose (a sugar found in sugarcane waste) into hydrogen and ethanol, which are useful biofuels.

Another more significant shift in the industry has come from the agriculture sector, where vinasse is being viewed not just as a waste product but as a resource for the application and the development of sustainable fertilizers, focusing on the nutrient-rich content and its role in reducing synthetic fertilizer use. Studies highlighted how vinasse could provide both environmental benefits and economic returns.

Carpanez, T.G. et al. [25] explore the potential of using sugarcane vinasse as a feedstock for producing organo-mineral fertilizers. The review discusses how vinasse contains essential nutrients like nitrogen, phosphorus, and potassium, which are important for plant growth. However, raw vinasse has challenges, such as low pH and COD, high organic matter content, and the risk of contamination due to trace metals and phenolic compounds. The article highlights that converting vinasse into organo-mineral fertilizers could be an effective way to reduce its environmental impact while providing a controlled and more stable fertilizer product. Despite its potential, the use of vinasse-based fertilizers requires further research to optimize the production process, control nutrient concentrations, and mitigate the risks of contamination. Research emphasizes the need for further studies to ensure that the environmental and economic benefits outweigh the risks.

3.2. Chronological Analysis of Vinasse Byproduct Patent Documents

General Evolution of Byproduct Technology

The utilization of vinasse, a byproduct of agricultural and industrial processes, has evolved significantly over the years, transitioning from basic waste management to innovative, sustainable applications (Figure 3). The periodization into “pre-2015 years: Early development”, “2015–2020 years: Growth phase” and “2020-present: Recent advances” reflect distinct phases of the technological activities observed. Early-stage patents filed before 2015 primarily address basic treatment approaches and fundamental research, while those from 2015 to 2020 demonstrate more applied developments, including integrated bioprocess and the use of vinasse for specific byproducts such as biofertilizers and biogas.

In the period after 2020 and recent advances, there is evidence of growing interest in higher value applications and optimization strategies, suggesting a transition towards more advanced and potentially scalable technologies.

Initially, vinasse was used in basic applications, such as animal feed and composting, with a focus on waste reduction and resource recovery. Over time, vinasse utilization saw significant refinement, with the development of advanced techniques and integrated systems. In recent years, vinasse utilization has entered a new era of being driven by precision technologies and multifunctional applications. These advancements highlight the versatility of vinasse and its role in promoting sustainable development, reducing environmental impact, and supporting the transition to a circular economy.

Pre-2015: early developments. In the early years, the number of patents was minimal. The focus was on basic applications of vinasse, with an emphasis on waste reduction, resource recovery, and low-cost solutions. Patent documents from this period laid the foundation for vinasse utilization across various sectors, but the technologies were often rudimentary and lacked integration. Friedmann, H. [26] describes an apparatus designed for converting fermentation stillage into biogas. A distinctive feature of the invention is the combination of a single-stage separation unit and a heavy-duty biogas reactor, which is designed with a pore-free flow path, making the process more efficient. This setup aims to improve the biogas production process by better handling the fermentation byproducts and reducing nitrogen levels, thus creating a more sustainable method for managing waste in ethanol production.

Mahler, J. [27] presents a method for producing bioethanol and energy. A key contribution of the method is the inclusion of a separation step, where the liquid phase and solid phase are separated from the fermented mixture through filtration and pressing before the distillation process. Additionally, the method utilizes light vinasse to produce a first fuel for energy coproduction, particularly thermal energy. This approach integrates bioethanol production with energy recovery, enhancing the overall efficiency of the process. Pollert, G. et al. [28] describe an energy-optimized method for operating a bioethanol production plant. This closed-loop system reduces the consumption of fresh water across the overall process, contributing to a more sustainable and energy-efficient production method. The key innovation lies in the combined operation of the two production systems to enhance resource utilization and minimize water usage.

Carthery Arnoldo, L.J. et al. [29] focused on a method for improving the process of converting organic waste into biofuel, specifically targeting the conversion of lignocellulosic biomass. This method is designed to enhance the efficiency and cost effectiveness of biofuel production by improving the yield and reducing the environmental impact of the process. The invention also includes specific conditions and enzyme formulations that optimize the conversion process, making it a noteworthy advancement in biofuel technology. Chaowei, L.; Baoku, Z.; and Lei, G. [30] provide a method for the efficient on-site utilization of distillate spirit vinasse in distilleries. The process starts with anaerobic digestion, where microorganisms break down vinasse to produce biogas. This biogas is then used for heating, cooling, and power generation and can also be purified into natural gas. The leftover liquid is recycled or used as fertilizer, while the solid residue is dried and used as fuel. Additionally, rice hull ash is repurposed for agriculture, and biogas residue is turned into organic fertilizer.

In 2013, a pivotal patent trend was filed that focused on converting vinasse into biogas through anaerobic digestion processes. Yanjun, X et al. [31] describe a method for preparing fuel gas and biogas-based fertilizers using beer brewing waste materials. The process involves three key steps: raw material composition, fermentation, and analysis of the fermentation product. This method is characterized by its simplicity, low operating costs, absence of secondary pollution, and ease of management, offering a sustainable approach to waste management and fertilizer production. This marked a major step forward, as it addressed energy recovery from vinasse, which became a key topic of interest for industries.

Wenwu, L. [32] presents a method for the comprehensive utilization of vinasse, which includes preparation and cracking, condensation, and biodiesel and pyrolysis gas extraction. The process also involves efficient resource recovery from vinasse. The method contributes to sustainable waste management by converting vinasse into useful products, reducing the need for disposal. It also creates high-value materials and energy sources, such as biodiesel and hydrogen, enhancing the economic value of vinasse.

Antti, V. [33] outlines a method for reducing the potassium content in vinasse. The process involves preparing a solution with vinasse, followed by the addition of ammonium sulfate under agitation to induce potassium precipitation. The invention aims to improve its suitability as a feedstock for bioethanol production, increasing efficiency in the process.

Zhenfen, W. et al. [34] describe a method for producing both biodiesel and animal feed from acorn vinasse. The process includes a stock solution separation, the extraction of essential components for biodiesel and feed, deoiling, transesterification, and rectification, where the biodiesel is refined to meet national quality standards. The process is efficient, low energy, and non-polluting, contributing to waste reduction and the sustainable use of agricultural byproducts.

Feibin, Z. et al. [35] introduce an animal feed and its preparation method, which offers several benefits, including reduced feed waste, the improved utilization of resources such as herbage, and a more balanced nutrient profile for the animals. It does not require additional auxiliary materials and is convenient for storage and transportation, making it ideal for large-scale farming operations. Hengrui, X. & Zuyou, X. [36] provide a method for extracting organic vitamins, phenol ester alcohol, and fermentation enzymes from Mountain Litsea or Fragrant Litsea fruit. The method allows for the efficient extraction of valuable compounds from the fruit, optimizing the production of phenolic ester alcohol and enzymes.

Some barriers that technology development faced in these years was the limited integration of processes, low efficiency in resource recovery and minimal focus on sustainability or circular economy practices.

Growth phase (2015–2020): refinement and integration. This phase marked a significant shift toward refined techniques, integrated systems, and a stronger focus on sustainability and circular practices. Patents from this period introduced more efficient methods for vinasse utilization, often combining multiple byproducts into a single process.

Zhenfen, W., Youyong, S. and Yiqun, Z. [37] disclose a device designed for producing biodiesel and fodder from acorn vinasse. The device is composed of several interconnected components to effectively process the vinasse and convert it into valuable products. The technology claims to be user friendly, optimized for practical use in biodiesel and feed production, and environmentally friendly, combining no harmful emissions with low energy consumption.

Shaobo, C. et al. [38] introduce a biorefinery integrated technique. The process begins with pretreating the material using an extractant to obtain pretreated material and leaching liquor. Pretreatment and extraction is followed by boiling with diluted acid to produce glucose, which is later turned into functional sugars. The remaining solid material is divided into two parts: one is used to create biocatalysts, and the other is processed into high-polymer lignin. Additionally, the process generates bioethanol, while liquid waste is fermented to produce methane for energy. The leftover vinasse is repurposed as animal feed or fertilizer, and CO₂ from fermentation is captured and transformed into food-grade CO₂.

Xuejin, L. [39] describes a method for producing worm feed using cassava alcohol residue (also known as cassava vinasse). This patent offers a sustainable approach to using cassava alcohol residue, typically a byproduct of ethanol production, by converting it into valuable animal feed. This not only helps in waste recycling but also supports worm farming by providing an enriched, well-balanced feed that boosts worm survival rates and growth.

Anxue, H. [40] presents a method for recycling waste gases from a breeding farm to promote ecological and circular economic practices. The process starts by treating corn, straw, wheat, and rice using a biological treatment system. These materials are then used for alcohol brewing, producing alcohol and vinasse. Vinasse is fed to pigs, reducing waste. Pig manure, urine, and wastewater are collected and processed to generate biogas. The biogas is used to produce electricity, powering the waste recycling system. This closed-loop system integrates livestock farming, bioenergy production, and waste management.

Fang, Q. [41] presents a system for recycling waste resources generated in the brewing of white spirits. This system cleans and reuses vinasse while generating biogas and fertilizers through a sustainable process. It includes a vinasse cleaning system that removes starch and protein, a sewage treatment system that processes the cleaned water to produce biogas, a boiler powered by biogas, coal, and rice hulls, which burns residual vinasse to create plant ash (potassium fertilizer), and solar power system and circulating water system to improve energy efficiency.

Changqiang, L. [42] reveals the use of a green feed additive in Eupolyphaga culture. This additive is composed of buckwheat, greater-leaf fast-growing cassia, bone meal, oil meal, berberine, white spirit vinasse, and urea. Compared to previous methods, this green feed additive offers several advantages: it uses natural raw materials, reduces costs, and provides excellent results. Also, the patent introduces the use of a green feed additive in freshwater turtle farming, which is made from a blend of natural ingredients. Compared to traditional methods, this green feed additive offers several advantages, including the use of natural raw materials, reduced costs, excellent performance, and potential large-scale implementation in turtle farming.

Notably, the patents highlight vinasse’s potential to replace traditional feed components, contributing to more sustainable production systems. The trajectory of these patents suggests an ongoing evolution toward more efficient, sustainable, and species-specific feed solutions, positioning vinasse as a valuable resource in the animal feed sector. Haijuan, G. [43] discloses a method for preparing a fertilizer using cow manure as the primary raw material. The steps include processing cow manure by stirring, crushing, and separating it into granular fertilizer and waste liquor; mixing vinasse, bran shell, and mushroom dregs into the fertilizer; and then fermenting it to create fruit tree fertilizer and sterilizing the waste liquor with lime water to produce animal feed for earthworms, chickens, or fish.

Covaliov, V., Covaliova, O. & Nenno, V [44] outline a combined method for producing biogas from various organic wastes, including vinasse, livestock and poultry wastes, food waste, and cellulose-containing waste like wood scraps and fallen leaves. The process uses anaerobic fermentation to convert vinasse biomass into methane gas, and then a hydrogen-containing gas is passed through the biomass, improving methane production. The hydrogen gas is generated by gasifying wood scraps and grapevine waste using a granular magnetite catalyst. The controlled gas mixture enhances biogas yield and produces organic–mineral fertilizers. This method maximizes waste recycling, creating renewable energy and sustainable fertilizers.

Compared to early developments, in this phase, the technology increased its focus on sustainability and waste reduction. Also, innovations showed an integration of multiple byproducts into single processes (e.g., bioethanol and biogas coproduction) and the development of species-specific and precision formulations (e.g., tailored animal feeds). New limitations came such as scaling technologies for large-scale implementation and balancing cost effectiveness with sustainability goals.

Recent advances 2020-present: sustainability and innovation. The most recent phase emphasizes sustainability, circular economy practices, and advanced technologies for optimizing vinasse utilization. Patent documents from this period focus on maximizing resource efficiency, minimizing waste, and creating multifunctional applications for vinasse byproducts.

Zongming, T. [45] describes a commercial wormcast organic fertilizer made from 100% pure wormcast. The fertilizer is produced by feeding earthworms with a specialized breeding feed that consists of 5% dehydrated cow dung, 15% fresh cow dung, and 80% cassava vinasse by mass. The resulting wormcast organic fertilizer is rich in nutrients and beneficial bacteria, promoting plant growth. It enhances soil structure and fertility, ensuring better crop yields and nutritional content. This fertilizer improves the quality and safety of crops, providing an effective solution for sustainable agriculture.

Jian, Z. et al. [46] relate to a cellulase system that enhances the conversion of corn fiber sugar into a saccharified liquid, which can be used as a feedstock for ethanol production. While its direct focus is not on biodiesel, the principles outlined in the patent can be applied to biodiesel production through the handling of vinasse and the optimization of enzyme systems that can be applied in biodiesel production processes. The enzymatic optimization introduced in this invention for better conversion could also apply to the treatment of biomass in biodiesel production to enhance oil extraction or conversion processes, improving overall yield and sustainability.

Jiying, Y. et al. [47] present an ecological breeding method that improves the feeding value of ground-source pig feed by fermenting raw materials such as vinasse, rapeseed meal, and bean dregs. Additionally, pig manure, combined with fresh bagasse from a sugar refinery, is used to produce an earthworm-feeding substrate through combined fermentation. This substrate is cost effective, simple to produce, and supports the industrial breeding of earthworms, increasing their survival rate and improving both their yield and quality. The process results in the production of earthworm cast organic fertilizer, earthworm hormone enzyme additives, and earthworm powder protein feed.

Jun, L. et al. [48] relates to a dual-purpose insect breeding soil formula used in food processing, which utilizes vinasse as the primary raw material. The method improves the survival rate of medicinal and edible dual-purpose insects by using vinasse as a base, reducing feeding costs. These grains undergo digestion and metabolism by the insects, ultimately transforming into organic fertilizer. This approach reduces secondary environmental pollution and enhances the high-value utilization of vinasse, addressing issues related to their large yield, rapid decay, and limited high-value applications.

Ziqiang, Z. et al. [49] introduce a method for safely applying fermented liquor from sauce-flavored liquor production as a fertilizer. This process involves fermenting the sauce-flavored liquor residue to obtain biogas slurry and then determining the safe application quantity of this slurry for soil. The method ensures that the slurry is applied in amounts that do not exceed the land’s capacity to avoid soil damage or pollution. The method aims to prevent secondary pollution and provides a sustainable approach for utilizing biogas slurry as a high-nutrient organic fertilizer.

Jihang, C. [50] discloses a distributed, environmentally friendly method for treating organic solid waste. The process involves treating kitchen waste, excess sludge, vinasse, or crop straw with preliminary anaerobic digestion. Wastewater sludge is then subjected to plasma treatment to produce anaerobic sludge, which is inoculated into the previously digested organic solid waste for secondary anaerobic digestion. This treatment method converts all the organic solid waste into biogas, methane, biogas slurry, and biogas residues. The key advantage of this method is that it transforms waste into valuable resources that can be directly used without requiring further treatment. The resulting biogas slurry can be mixed with biogas residues to create a fertilizer that is ready for agricultural use without the need for additional processes like degradation or aeration.

Xiangyun, L. [51] presents a method for treating vinasse through a combined approach using acid, alkali, and enzyme hydrolysis to efficiently treat vinasse with 50–60% water content, improving resource extraction. The process is mild, without the need for high-pressure or high-temperature equipment, making it easier to control and more cost effective. Fewer byproducts (like furfural) are generated compared to traditional methods, ensuring better sustainability. The method is low cost and energy efficient, as it avoids the need for specialized high-pressure or high-temperature equipment. It provides a sustainable way to extract valuable resources, such as sugars, from vinasse, making it more economically viable for distilleries to recycle this byproduct.

Anjun, L. et al. [52] provide a method for preparing selenium-rich vinasse feed, which involves using fermentation techniques to enhance the nutritional value of vinasse. The process converts inorganic selenium into organic selenium through microorganisms, improving the bioavailability of selenium in animal feed. The resulting selenium-rich feed has an improved biological antioxidant capacity, which can enhance the immunity and antioxidant functions of animals. The feed improves the growth performance of ruminants, offering an effective way to enhance animal health and productivity, promoting a circular economy in the agricultural and livestock sectors.

Unlike the growth phase, recent advances have strong emphasis on circular economy practices, with vinasse being used as a key feedstock for multiple high-value products. Also, the development of precision technologies to improve efficiency and yield were reported (e.g., enzymatic optimization and targeted extraction), as well as the integration of advanced analytics for process optimization. Nevertheless, new limitations arise, such as ensuring economic viability while maintaining sustainability goals, addressing regulatory and environmental concerns related to large-scale vinasse utilization, and the development of global standards for vinasse-based products to facilitate market adoption.

3.3. Subject Area of Scientific Articles

Environmental Sciences leads the chart at 26.8%, indicating the strong focus on the environmental implications of vinasse byproducts. This is not surprising given the need to develop sustainable solutions for managing the large volumes of waste produced, especially in the agricultural and bioenergy sectors. The emphasis on Environmental Sciences reflects the global push towards sustainability and waste reduction, areas where vinasse management plays a significant role (Figure 4).

Following closely, Agricultural and Biological Sciences accounts for 17.1%, which is highly relevant given vinasse’s direct relationship with agriculture, particularly in biofuel production from crops like sugarcane and corn. Researchers in this field focus on improving agricultural practices, soil health, and the biological aspects of vinasse treatment.

Chemical Engineering (11.1%) and Energy (10.4%) are also key contributors, emphasizing the technological and energy recovery aspects of vinasse byproducts, such as bioenergy production, biofertilizers, and other value-added products. Engineering (7.9%) and Chemistry (4.9%) further support the development of innovative technologies to process and valorize vinasse.

The presence of more specialized fields, such as Biochemistry, Genetics, and Molecular Biology (6.1%), demonstrates the interest in the molecular and biochemical mechanisms involved in vinasse’s transformation, particularly for its use in biofuels and other bioproducts. Finally, the “Others” category (15.7%) encompasses a variety of interdisciplinary contributions that support the broader field of vinasse byproduct research.

3.4. Technological Domains of Patent Documents

Bioethanol is the most significant byproduct. The dominance of bioethanol suggests that the technology or process employed is optimized for efficient ethanol production, which has high demand in the energy sector due to its role in reducing carbon emissions and the dependency on fossil fuels (Figure 5).

The second largest share is occupied by biofertilizers, representing a valuable use of waste byproducts, offering a cost-effective and environmentally friendly alternative to synthetic fertilizers. Animal feed occupies the third place, reflecting the use of organic waste in livestock and aquaculture nutrition. Animal feed production from waste material like vinasse or other organic residues helps reduce costs in animal husbandry while offering a sustainable solution for waste disposal. The significant share of animal feed also reflects its growing importance as a substitute for more conventional feed sources, which can be expensive and resource intensive.

Biogas is produced through anaerobic digestion, which transforms organic waste into renewable energy. While this percentage is relatively small compared to bioethanol or biofertilizers, it still represents a valuable source of clean energy. Its production can be integrated with other byproduct streams, creating a more sustainable process that reduces reliance on external energy sources and contributes to energy independence.

While biodiesel production is a common goal in many biorefinery operations, its lower share may suggest that the feedstock or technology used in this process is more suited for other biofuels or products like bioethanol. The relatively small proportion of biodiesel might also reflect market conditions or technical limitations in scaling up its production from the given waste material.

On the other hand, although phenolic compounds have potential applications in industries such as nutraceuticals, food additives, and cosmetics, their extraction is not the primary focus of this process. The small proportion of phenolic compounds could indicate challenges in extraction efficiency or a lower market demand relative to other byproducts like bioethanol or fertilizers.

3.5. Country of Origin of Patent Documents and Scientific Articles

Patents are inherently territorial, meaning they are granted and enforced within specific jurisdictions, with each country establishing its own system for granting patent rights. In addition, the number and scope of patents filed in a particular country often serve as indicators of the nation’s capacity to foster innovation and develop industries around specific technologies. High levels of patenting activity in certain sectors can reveal a country’s competitive edge, research and development investments, and technological expertise [53].

By analyzing patenting trends, it becomes possible to assess the technological priorities of a nation, as well as its ability to create, protect, and commercialize new technologies. This capacity is not only a reflection of domestic research output but also of the ability to integrate innovation into broader economic and industrial strategies.

Regarding patent documents related with vinasse byproducts, China’s dominance in vinasse byproduct patents can be attributed to its large-scale agricultural sector and strong focus on sustainable practices in its industrial policies. As a major producer of agricultural waste, including vinasse from ethanol production, China has increasingly invested in finding innovative ways to manage and utilize these byproducts. This investment is closely linked to the country’s broader environmental goals, such as reducing waste and enhancing the use of biofuels and bioproducts (Figure 6).

Additionally, the robust infrastructure for industrial-scale research and development in China, supported by both government initiatives and private-sector collaboration, is a key factor driving the high volume of patents in this area [54].

The United States, while ranking second in patent activity, demonstrates a different set of influences. The U.S. has a well-established biotechnology and environmental technology industry, supported by significant investment in research and development across universities, research institutions, and private companies [54]. The strong focus on sustainability and renewable energy solutions, including the bioeconomy, positions the U.S. as a major player in advancing technologies related to the treatment and valorization of agricultural waste, such as vinasse. The U.S. also benefits from a highly competitive and innovative patent system that encourages the protection of intellectual property and the commercialization of new technologies.

Mexico’s significant position in the map highlights its important role in both vinasse production and innovation in the treatment of agricultural byproducts. As one of the leading countries in bioethanol production, particularly from agave, Mexico faces a growing challenge in managing the environmental impact of vinasse. This has driven the country to focus on technological solutions for the effective treatment and valorization of vinasse.

On the other hand, the distribution of scientific articles across territories provides valuable insights into the scientific capacities of different regions, reflecting the depth of research activities and the focus of scientific efforts within each territory. The volume of articles can thus serve as an indicator of the intellectual resources dedicated to a particular technology or industry, revealing the territories where scientific expertise and research infrastructures are most advanced.

Brazil, with the largest share at 45.1%, is a leader in vinasse-related research. As a major producer of ethanol from sugarcane, Brazil faces a pressing need to manage the environmental impact of vinasse, driving the country’s significant research output. Mexico follows at 10.6%. The country’s focus on research in vinasse treatment is closely tied to its industrial tequila production and bioenergy sector, aiming to minimize environmental impacts while enhancing resource recovery. Spain’s 10.1% share reflects its role as a key European research hub in bioenergy and agricultural waste management, where scientific efforts focus on innovative treatments for byproducts like vinasse (Figure 7).

China, despite having a notable share of patent filings related to vinasse byproducts, has a more pragmatic and application-focused approach in its research and development. In contrast to the research-driven publications seen in Brazil, Mexico, and Spain, China’s emphasis on patents highlights its strategic intent to translate scientific research directly into marketable technologies. This pragmatic approach underscores the country’s desire to scale up and implement technology solutions quickly, particularly in areas like waste management and biofuel production. The patenting activity indicates that China is prioritizing technological development over academic dissemination, aiming for rapid industrial application and commercialization of innovations in the vinasse byproduct sector.

Among the top contributors, M. Zaiat from Brazil stands out with 25 publications, followed by L.T. Fuess with 20 publications and M.C.S. Amaral with 19. This strong representation of Brazilian researchers underscores the country’s leading role in the scientific investigation and innovation surrounding vinasse byproducts (Figure 8). It is important to note that several authors identified in this network have contributed primarily to sugarcane vinasse research, which shares similar characteristics with tequila vinasse and its often used as a reference in technological development. The prominence of Brazilian authors reflects Brazil’s position as a major producer of vinasse, particularly as a byproduct of its large ethanol production industry, which drives significant academic and industrial interest in sustainable solutions for vinasse treatment and valorization.

Other notable contributors include E.L. Silva (Brazil, 16 publications) and H. Cantarella (Brazil, 12 publications), further supporting the idea that Brazilian researchers are the primary drivers in advancing the scientific understanding of vinasse. Additionally, Mexico is represented by M. Méndez-Acosta, who has 14 publications. This suggests that Mexico, with its own large-scale bioethanol production from sugarcane, corn, and agave, also plays a significant role in vinasse research, likely focusing on environmental and agricultural applications.

Although Brazil and Mexico dominate the research landscape, Poland’s Krzywonos and Rodrigues (Brazil), with 11 publications each, indicate a growing international interest in the topic. The involvement of Polish researchers reflects an expanding global network of scholars and institutions dedicated to addressing the challenges and opportunities of vinasse byproducts.

The top 10 universities and research institutes that publish the most, according to the affiliation of the authors, are based primarily in Brazil and secondly in Mexico. The top five universities are Universidade de São Paulo (148 scientific articles), Universidade Estadual Paulista Júlio de Mesquita Filho (90 scientific articles), Universidade Federal de São Carlos (54 scientific articles), Universidade Estadual de Campinas (52 scientific articles), and Universidad de Guadalajara (35 scientific articles).

3.6. Technological Prospection

Companies are the dominant patent applicants, representing 43.8% of the total. This suggests that the private sector plays a leading role in the commercialization of vinasse-related technologies, likely driven by the potential for industrial-scale applications, such as bioenergy production and waste management solutions. This relation highlights the industry’s active involvement in applying for patents to protect proprietary innovations (Figure 9).

Universities and public research centers/institutes come in second place at 16.1% and 16.3%, reflecting the strong role of academic research in advancing scientific knowledge and technological development in the field. Universities often act as hubs of innovation, where research projects can be translated into patentable inventions through collaborations with industry partners. Public research institutes also indicate a supporting role in fostering innovation and research initiatives aimed at addressing environmental and agricultural challenges related to vinasse.

4. Discussion

The valorization of tequila vinasse has attracted significant interest in both scientific and industrial development due to its high pollution potential and the growing need for sustainable waste management. While this review confirms a growing volume of research and patenting activity, the translation from laboratory to industrial application remains uneven.

The technological evolution of vinasse valorization reflects a shift from basic waste management practices to integrated multifunctional systems aligned with circular economy principles. Early patents (pre-2015) focused on isolated applications such as composting or biogas production, offering incremental improvements with limited scalability. Between 2015 and 2020, innovation accelerated, with invention activities increasingly targeting integrated biorefinery models that combined energy recovery, nutrient recycling, and feed production. Post-2020 patents indicate a move toward precision technologies, including enzymatic catalysis and microbial formulations, reflecting the pursuit of specialized higher products.

From a technological readiness level, most patents analyzed fall within early- to mid-stage development, particularly in fields like biofertilizers and phenolic compounds. In contrast, bioethanol and biogas technologies have reached higher maturity levels, with some processes integrated into large-scale operations.

This technological progression is reflected in the territorial distribution of patents. China leads technological developments, emphasizing rapid industrial deployment and government-backed sustainability strategies. The United States, although second in volume, focuses on foundational and cross-sectorial innovation. In contrast, Brazil leads in scientific publications but lags in patent filings, indicating a weak research-to-market pipeline. Mexico, despite being a major vinasse producer, shows moderate patent activity, highlighting the need for stronger technology transfer mechanisms in the tequila sector.

Patent categorization reveals bioethanol as the most dominant domain, benefited by established markets and infrastructure, followed by biofertilizers, animal feed, and biogas, emerging applications that demonstrate increasing industrial relevance. The lower patent share of phenolic compounds may reflect extraction challenges and market fragmentation, despite its high potential value.

Applicant profiles support this commercial orientation, since private companies account for nearly half of all patents, suggesting active IP strategies for securing market advantage. Universities and public research institutes contribute significantly to early-stage innovations

The focus has been on optimizing the treatment and valorization of vinasse to address environmental and economic concerns. In both patent documents and scientific articles, several trends have emerged, mostly focused on sustainability and environmental impact. By the 2016–2020 period, the number of patents reached a significant peak in these years, driven by the need for more efficient processes to convert vinasse into biogas, bioethanol, and animal feed. There was also a noticeable shift towards industrial applications.

A significant body of research is dedicated to reducing the environmental footprint of vinasse disposal. Efforts to develop sustainable, low-cost treatment methods such as anaerobic digestion, co-digestion with other waste materials, and chemical treatments are gaining traction. Patents show that these technologies are being refined to improve biogas production, wastewater treatment, and nutrient recovery from vinasse, reflecting a growing alignment with global sustainability goals.

There is a clear trend in the research towards converting vinasse into energy. Several studies focus on optimizing the anaerobic digestion process, co-digestion with other agricultural wastes, and the use of specialized bioreactors. Another significant trend is the exploration of vinasse as a soil conditioner and fertilizer. Research has highlighted its potential in improving soil fertility, especially in regions where agriculture is a major economic activity.

The nutrients in vinasse, including potassium, nitrogen, and organic matter, offer a valuable resource for enhancing crop yields. However, concerns about the balance of nutrients, toxicity, and long-term soil health must be carefully managed. Patents in this area focus on treatments that reduce toxicity and improve nutrient bioavailability. Nevertheless, the transition from academic research to technology application remains limited. The long-term impact of large-scale vinasse application on soil health and the environment remains an open question. Research must continue to monitor the effects of vinasse applications to ensure its use do not lead to nutrient imbalances, soil salinization, or the contamination of water sources.

The potential market for vinasse byproducts is expected to grow as more countries and industries focus on circular economy models and sustainability. The market for biogas, biofertilizers, and organic waste management is poised for expansion, particularly in regions with a strong agricultural base and bioenergy production, such as Brazil, India, and the U.S.

The results show that vinasse is not only an environmental liability but also a resource with substantial commercial and sustainability potential. As noted by Fit et al. [55], in biorefinery frameworks, vinasse offers multiple entry points into bio-based markets through the production of energy vectors, biopolymers, enzymes, and microbial biomass, especially with other agricultural residues.

However, the economic viability of vinasse byproduct technologies depends on reducing operational costs, improving efficiency, and ensuring that these technologies can scale up to meet industrial demands (Figure 10). Despite recent advances, many of these processes and technologies remain at the laboratory or pilot scale, facing significant challenges in scalability and process integration. Economies of scale will be crucial to making vinasse treatment and valorization commercially viable in the long run; therefore, reducing operational costs and enhancing process efficiency are essential for making these technologies competitive with conventional alternatives.

From a regulatory perspective, as the global push for climate change mitigation intensifies, there is a notable policy uncertainty on vinasse and waste management. This ambiguity can act as a disincentive for private investment and industrial adoption.

From a sustainability perspective, the valorization strategies show marked improvements in waste minimization, energy recovery, and nutrient recycling. These achievements represent a shift from conventional treatment models to resource recovery paradigms, aligning with bioeconomic principles. These developments indicate that vinasse can be positioned at the center of integrated bioindustrial clusters, supporting local circular economies and the development of high-value industries [56]. Moreover, the economic feasibility is often limited by the high costs associated with pretreatment, downstream separation, and product purification.

The long-term impact of large-scale vinasse application on soil health and the environment remains an open question. Research must continue to monitor the effects of vinasse as a fertilizer to ensure that its use does not lead to nutrient imbalances, soil salinization, or the contamination of water sources.

The future of vinasse byproduct technologies looks promising, particularly in the context of sustainable energy and agriculture. While there are still hurdles to overcome, the continued focus on innovation, optimization, and sustainability will drive the growth of vinasse byproduct technologies, presenting both significant opportunities and challenges for the future.

5. Conclusions

The tequila industry, while experiencing significant global growth, faces substantial environmental challenges due to the large-scale production of vinasse. Traditional disposal methods have led to serious ecological concerns, including water contamination and soil degradation. This review confirms that vinasse is increasingly recognized as a resource for producing a variety of bio-based products, notably bioethanol, biofertilizers, biogas, animal feed, and phenolic compounds.

The majority of technologies identified remain in early development stages and re-quire further validation under industrial conditions. The lack of economic assessments, unresolved challenges in residual toxicity and uncertain regulatory frameworks restrict the commercial potential of these technologies.

However, recent advancements in bioeconomy-driven technologies have opened new opportunities for sustainable vinasse management. The adoption of circular economy models enables the transformation of vinasse into valuable byproducts, reducing environmental impact while generating economic benefits.

Vinasse, historically considered a waste material, is now recognized as a resource for producing biofuels, biofertilizers, biogas, animal feed, and phenolic compounds. The integration of patent-protected innovations into the tequila industry represents a shift toward sustainable production, where technological solutions optimize resource recovery and waste minimization. Scientific research and industrial advancements have demonstrated the feasibility of commercializing vinasse-derived products, making them economically viable. Furthermore, regulatory frameworks and industry collaborations are fostering the large-scale adoption of vinasse-based technologies, ensuring their scalability and long-term sustainability.

The tequila sector stands at a crucial turning point where innovation, sustainability, and economic opportunity converge. In order to achieve a sustainable transition, several actions are needed, such as the creation of public–private partnerships to support producers in adopting vinasse valorization technologies, the application of regulatory frames that support circular bioeconomy projects. and the application of interdisciplinary research to assure technical and commercial feasibility of vinasse byproducts. Future research should focus on economic assessments, technological validation, and policy frameworks to support commercialization. The valorization of vinasse aligns with global in bioeconomy and circular economy trends, offering a model for other agro-industries facing similar challenges. By investing in technological advancements and sustainable practices, the tequila industry can significantly reduce its environmental footprint, strengthen its competitiveness, and pave the way for a greener future.