Review Reports - A Comprehensive Review of Non-Destructive Monitoring of Food Freshness and Safety Using NIR Spectroscopy and Biosensors: Challenges and Opportunities

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I have accepted the review, because I expected a manuscript with applications/work which have/has been investigated/performed by the authors.

However, after studying the manuscript, I realized that it is - at best - a literature review of existing work. Such a literature review may also be of value for the readers of this journal, but should be clearly reflected in the title of the manuscript.

The figures are graphical abstracts taken from other authors (cited correctly) but are not alway easy to read (actually in Fig. 1 the graphical abstract is upside-down).

There was not one Fig. with an NIR spectrum measured by the authors in connection with their own research work. In view of my NIR expertise (and not biosensors) my opinion is therefore not really relevant.

Generally, the text is well written (I hope the editors can check whether ChatGPT !), thus it may serve as an existing literature source for the readers. If this is fine for the editors, go ahead with publication, but my understanding of the title was completely different.

Author Response

Reviewer #1:

I have accepted the review, because I expected a manuscript with applications/work which have/has been investigated/performed by the authors. However, after studying the manuscript, I realized that it is - at best - a literature review of existing work. Such a literature review may also be of value for the readers of this journal, but should be clearly reflected in the title of the manuscript. There was not one Fig. with an NIR spectrum measured by the authors in connection with their own research work. In view of my NIR expertise (and not biosensors) my opinion is therefore not really relevant.

Generally, the text is well written thus it may serve as an existing literature source for the readers. If this is fine for the editors, go ahead with publication, but my understanding of the title was completely different.

Re: Thank you for your comment and input on our work, we would like to clarify that this manuscript is designed solely as a comprehensive review article and not as a research article hence why the figures are adapted and sourced from other papers. We have revised the title to indicate that this manuscript is a review paper.

Reviewer 2 Report

Comments and Suggestions for Authors

This review article, entitled “Non-Destructive Monitoring of Food Freshness and Safety Using NIR Spectroscopy and Biosensors: Challenges and Opportunities,” introduces a variety of techniques used in biosensing for food. This review article references a sufficient number of previous papers and covers numerous topics, potentially providing value to readers. However, it seems to be a problem that the description on each topic is superficial. In addition, the figures in each section are not consistent with the main text. The figures are reused from some references, and some of them include detailed information on the original works, such as experimental data. However, the main text describes only a superficial introduction to the concepts of biosensing strategies, and therefore, the figures and the main text are inconsistent with each other. Moreover, the referred papers in the relevant portion of the main text differ from those for the figures. For example, the contents in the panels in Figure 4 are not described in the main text following line 232, where Figure 4 is mentioned. Such inconsistencies between the main text and the figures will confuse readers and prevent understanding. In addition to the example in Figure 4, all figures must be reviewed to ensure they are consistent with the content of the main text. Figure 5 is a conceptual schematic of fluorescent probes and, therefore, does not seem appropriate for explaining the details of their use in monitoring food freshness and safety. To address these issues and enhance this review article, the reviewer recommends that the authors prepare original figures to illustrate the main text's contents. Since this review article covers various measurement technologies, the illustration of the technological principles in detail will help the readers ' understanding.

Author Response

Reviewer #2:

Re : Thank you for your insight, the sections have been revised and given more details while trying to reduce the lengthiness of the paper. Also the figures have been realigned to match each section and all the panels in every figure have been discussed in the main text throughout the manuscript. Figure 1 can be found from lines 79-86, Figure 2 from lines 165-181, Figure 3 from 273-289, Figure 4 from 325-334, Figure 5 from 341-358, Figure 6 from 394-414, Figure 7 from 471-479, Figure 8 from 521-539, Figure 9 from 558-575, figure 10 from 630-649 and Figure 11 from 763-778 in the main text of the manuscript. The conceptual schematic of fluorescent probe image has now been replaced with a new figure which is now the current figure 4 all other figure numbers have been adjusted accordingly.

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript is a narrative review on non-destructive monitoring of food freshness and safety using NIR spectroscopy and biosensors, with emphasis on recent portable devices, chemometrics/AI, and hybrid NIR–biosensor systems. However, the work is a descriptive overview, formal evidence synthesis, or critical appraisal. Figures and tables compile examples but need sourcing and standardization, and several editorial and referencing issues limit clarity and credibility. The reviewer encourages a careful, method-first revision to raise rigor and usability:

Several statements extrapolate performance or readiness for “real-time” or “industry” deployment without discussing negative findings, failure modes, or effect sizes.
Captions describe complex workflows but omit instrument models, acquisition modes, wavelengths, or dataset sizes underlying the depicted pipelines
Entries mix R², Accuracy, RPD, RMSE, and qualitative notes without harmonized definitions; some lines truncate or lack RMSE/CI, and sample sizes are not consistently reported
Several LODs/targets are listed without matrices, validation details, or confirmation that methods are food-matrix validated rather than buffer-only
The hybrid NIR–biosensor section blends optical SERS platforms and general biosensing without clearly established, simultaneous hybrid deployments in real chains
Sections alternate between Vis-NIR and NIR without clarifying spectral ranges or implications for penetration depth and analyte specificity
Define all abbreviations at first use (e.g., TVB-N, OPLSR, RPD, LDA/QR, DAO)
Move speculative content on blockchain/IoT to a shorter outlook with concrete references to deployments, or support with more specific implementation examples

Comments on the Quality of English Language

Standardize hyphenation and terms: “in-line/inline,” “on-line/online,” “smartphone-integrated.” Fix spacing and punctuation (e.g., author list commas and spaces around numerals/superscripts)

Author Response

Reviewer #3:

Q1 :Several statements extrapolate performance or readiness for “real-time” or “industry” deployment without discussing negative findings, failure modes, or effect sizes.

Re: Thank you for your careful review, we have revised the overstated claims and the discussions now highlight the limitations such as environmental variability, calibration drift etc. that may hinder industry deployment. Changes have been made throughout the manuscript

Q2: Captions describe complex workflows but omit instrument models, acquisition modes, wavelengths, or dataset sizes underlying the depicted pipelines

Re: We appreciate your thorough reading the figure captions have been revised to include relevant technical details such as instrument models, acquisition modes, wavelength ranges, and dataset sizes where applicable.

Q3:Entries mix R², Accuracy, RPD, RMSE, and qualitative notes without harmonized definitions; some lines truncate or lack RMSE/CI, and sample sizes are not consistently reported

Re: Thank you for pointing this out, after going through the manuscript we have standardized all statistical metrics and clearly defined R², RMSE, RPD, and Accuracy within the Results and Tables. Incomplete entries were corrected, and sample sizes and confidence intervals are now consistently reported (see Table 2 and Section 4.3).

Q4: Several LODs/targets are listed without matrices, validation details, or confirmation that methods are food-matrix validated rather than buffer-only

Re: Thank you for your remarks the validation details have been clarified. Only methods verified in real food matrices are now described as validated. Studies conducted in buffer systems are noted as “pre-validation” cases. This revision appears in Section 4.3.

Q5:The hybrid NIR–biosensor section blends optical SERS platforms and general biosensing without clearly established, simultaneous hybrid deployments in real chains

Re: Thank you for your comment to help make our manuscript better, we have revised Section 4.2 and 4.3 to clearly distinguish between SERS-based optical biosensors and true hybrid NIR–biosensor platforms.

Q6:Sections alternate between Vis-NIR and NIR without clarifying spectral ranges or implications for penetration depth and analyte specificity

Re: We are grateful for your careful review of our work, The manuscript now defines both spectral regions (Vis-NIR: 400–1100 nm; NIR: 780–2500 nm) and discusses their respective penetration depths and can be found in section 2.. These clarifications improve technical precision.

Q7:Define all abbreviations at first use (e.g., TVB-N, OPLSR, RPD, LDA/QR, DAO

Re: Thank you for pointing this out and we agree with your comment, All abbreviations (e.g., TVB-N, OPLSR, RPD, LDA/QR, DAO) have been defined to improve readability and accessibility for non-major related readers.

Q8:Move speculative content on blockchain/IoT to a shorter outlook with concrete references to deployments, or support with more specific implementation examples

Re: We appreciate your suggestion, Section 4.4 was condensed to a concise outlook paragraph. The revised version includes concrete examples of IoT and blockchain-enabled traceability in real food supply chains.

Q9:Standardize hyphenation and terms: “in-line/inline,” “on-line/online,” “smartphone-integrated.” Fix spacing and punctuation (e.g., author list commas and spaces around numerals/superscripts)

Re: Thank you for pointing this out, All instances of “on-line/online,” “in-line/inline,” and “smartphone-integrated” have been standardized accordingly. Spacing, punctuation, and superscript formatting have also been carefully corrected across the manuscript.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

In the last comment, the reviewer noted that the figures in this manuscript are those from the referenced papers and do not adequately illustrate the contents of this review article. For example, Figure 2B shows various raw and processed spectra, but there is no description of what the 6 graphs represent. The original data themselves are not essential for this review article, but the generalized process should be explained in the manuscript. Although it is acceptable to use figures from the reference papers, they should be modified to reflect the contents of the review article, as the reviewer mentioned in the previous comments that “the reviewer recommends that the authors prepare original figures to illustrate the main text's contents”. The reviewer recommends revising all figures to clearly reflect the main text and help readers understand this review article in detail.

Author Response

Reviewer #2:

In the last comment, the reviewer noted that the figures in this manuscript are those from the referenced papers and do not adequately illustrate the contents of this review article. For example, Figure 2B shows various raw and processed spectra, The original data themselves are not essential for this review article,. Although it is acceptable to use figures from the reference papers, they should be modified to reflect the contents of the review article, as the reviewer mentioned in the previous comments that “the reviewer recommends that the authors prepare original figures to illustrate the main text's contents”.

Re : Thank you for the clarification and attention to detail in reading our manuscript. We have replaced Figure 2 and taken out the original data that is not essential for our manuscript. Kindly find the replaced the figure and the description from lines 163-178.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors provided further clarifications to comments and suggestions. I recommend the publication of the revised version

Author Response

Reviewer #3:

The authors provided further clarifications to comments and suggestions. I recommend the publication of the revised version

Re : Thank you for your positive feedback and for recommending the publication of the revised manuscript. We appreciate the time and effort you took to review our work and are glad that the clarifications and revisions have addressed the raised concerns effectively