Sustainable Emerging Proteins: Allergenic Proteins in Edible Insects, Microalgae, and Microorganisms, and Desensitization Processing Technologies

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript sounds interesting. However, it must be revised as per comments.

The manuscript “Alternative Proteins: Properties, Allergens and Desensitization
Techniques” is interesting and has good potential for publication. As the global population continues to expand and demand for protein increases, alternative proteins (e.g., edible insect proteins, microalgae proteins, fungal or bacterial proteins) have emerged as a significant area of research interest due to their high nutritional value and sustainability. However, these novel protein sources may contain allergenic components, such as tropomyosin and arginine kinase in insects, phycocyanin in microalgae, and ribosomal proteins in fungi, which may trigger allergic reactions and cross-reactivity with traditional allergens. I have the following comments to improve the manuscript:

 

Lines 31–36: The sentence claiming “world population and per capita calorie intake are expected to increase by 6 billion and 500 kcal per person per day, respectively, by the year 2100” is surprising and likely incorrect in wording (6 billion increase seems too large relative to current ~8 billion). If this originates from ref [1], please quote exact figures and include the year and source. If [1] is FAO scenario, rephrase precisely (e.g., “global population projected to reach X by 2100” with citation).

 Lines 9–27: There is methodology included in the abstract, please include a brief methodology.

Lines 30–80: The experimental section must have reproducibility and transparency.

Lines 193–201: Table 2 mixes different evidence levels (experimental IgE binding, sequence homology, predicted allergens) without distinguishing them.

Lines 444–513: Provide a short figure or table summarizing when heating is likely to reduce vs. increase allergenicity.

Line 637: Li et al. [187] developed a magnetic……..

 

Lines 645–675: The section mentions gaps but does not prioritize research needs (e.g., comprehensive proteomics, standardized IgE panels, clinical challenge studies).

Figures 1–4 are cited but figure legends are short or missing details (e.g., Figure 3 caption lacks explanation of symbols). Ensure every figure/table has a complete legend, units.

Line 731–738: Please rephrase to avoid double negatives and improve clarity.

 

Line 713–741: Please add 3–4 prioritized bullet recommendations for research and industry.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

English must be concise throughout the manuscript.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This review manuscript on alternative proteins, their allergenicity, and methods to reduce their allergenicity is a much-needed topic in the present world. However, certain issues need to be addressed before accepting it for publication. 

1. Why didn't the authors add tree nuts and oil seeds as a potential alternative protein, given the fact that those are the widely used alternative protein options?
2. Peanuts are listed as the most allergenic alternative protein. Including the allergenicity and the processing methods to reduce it would be highly important for this manuscript. Thus, I request the authors to add it into the manuscript.
3. Why did the authors only add the "Applications of Insect Protein and Microbial Protein in Foods" and left other potential proteins?
4. High pressure processing and ultrasound are nonthermal technologies and microwave is an alternate thermal technology. Ensure to add it in the appropriate subheading.
5.  I request the authors to add more details on each technology's mechanism involved in reducing the allergenicity
6. Why did the authors not include UV light, and irradiation technologies for allergenicity reduction?
7. Add suitable references for table 3. 
8. I also request the authors to reduce explaining more about the allergenic proteins and concentrate more on the methods used for reducing it.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

General comments

The manuscript by Xu et al. presents a comprehensive review on alternative proteins for food and the influence of food processing techniques on protein sensitization. The word “foods” should be present in the title. Overall, a good overview is presented, but some aspects, especially about official allergen names listed in the WHO/IUIS Allergen Nomenclature database, need to be improved as suggested below.

Specific comments

1-Page 2, line 62: Allergen Nomenclature Sub-Committee (not Panel).

2-Line 86: Orthoptera, Coleoptera, etc. are not species.  Therefore, this sentence needs to be re-phrased.

3-Figure 2: An increase in the size of the whole figure will increase font and make it more readable.  The species’ names should be in italics.

4-Line 143: the sentence seems incomplete. Should it be: “…are abundant, and can have…”? (which ones, the peptides or the yeast proteins, have positive effects?).

5-Table 1: L. migratoria, T. molitor (the second word of the species should be lower cap). Erişte at the bottom of Table in page 6: in capital.

6-Line 220: The correct name of this allergen is Bomb m1 (not Bom m 1). Line 225: Bomb m 3 is the correct name. Line 229: Bomb m 6. The official name Bomb m 6 (not Bmlp3) should be used in line 230. Line 233: Bomb m 4. Line 239: Bomb m 5. Line 240: Bomb m 6. However, in line 234, Bom m 9 is not an official allergen. Therefore, the authors should say that “another protein named Bom m 9 was reported as associated to asthma, but it is not officially listed in the WHO/IUIS Allergen Nomenclature database (www.allergen.org).” An asterisk could also be added to other proteins without official allergen names in Table 2.

7-Table 2 needs to be completed/corrected regarding cockroaches:

-Bla g 2 is an “inactive aspartic protease”.

-Bla g 4 MW needs to be completed

-Bla g 12 and Per a 14 to Per a 22 are missing.  The authors should refer to the official database (www.allergen.org) to complete Table 2.

The rest of Bla g proteins (enolase, vitellogenin, etc.) have not been officially accepted in the WHO/IUIS Allergen Nomenclature database. Therefore, they should be added to Table 2 as “candidate allergens”. To do so, an asterisk could be added, and in a footnote, something could be indicated in these lines: “* These proteins are not official allergens, but are allergen candidates, reported as IgE-binding proteins.”

8-Page 12, last paragraph of section 2.2.1. is about fungi, not microalgae, so that paragraph seems to be more appropriate for the next section 2.2.2. on fungal allergens. However, the fungal species mentioned are presented as sources of aeroallergens, not food allergens.  So, it is not clear if it should be used in this paper, which refers mainly to food protein alternatives. The same applies to Table 2 that should be corrected.

9-Only one allergen from bacterial origin is listed in the official allergen database: Bac s 1, and should be included in the paper since it is from a food (Japanese “natto”), along with its reference:

Kayoko Suzuki, Masashi Nakamura, Nayu Sato, Kyoko Futamura, Kayoko Matsunaga, Akiko Yagami. Nattokinase (Bac s 1), a subtilisin family serine protease, is a novel allergen contained in the traditional Japanese fermented food natto. Allergol Int. 2023 Apr;72(2):279-285. doi: 10.1016/j.alit.2022.11.010. Epub 2022 Dec 12.

 

Minor comments

Format of references should be consistent (e.g. ref 17 and 18 no need to capitalize all words in title; ref 98, 116, etc.).

Species names should all be in italics all over the manuscript, including references (e.g. ref 33, Figure 2).

Line 44: Period (not a circle) after the latin name.

Line 286: US population.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript has been revised as per comments.

Comments on the Quality of English Language

English has been fine now throughout the manuscript.

Author Response

We sincerely thank you for your affirmation of our research and your recommendation to publish it in the Foods.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have responded to most comments, but some still need to be addressed:

Line 92: “etc” should be removed.

Lines 228-248:  The names of certain allergens have not been corrected as requested in previous comment “Line 220”.

Bla g 12 is still missing in Table 2.

In Table 2, Bac s 1 is from the species Bacillus subtilis (not Bacteria Bacillota). This is a bacteria, not a microalgae.

Also, not all the organisms under “Microalgae” are not microalgae (Spirulina and Chlorella are but some are yeast, fungi, bacteria, etc.). This needs to be corrected in the Table, and us a different name than microalgae for all.

References still do not have all the same format (e.g. ref 17).

Everywhere, including Figure 3, species names should be in italics.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf