Current Status and Economic Prospects of Alternative Protein Sources for the Food Industry

Round 1

Reviewer 1 Report

Author Response

Reviewer #1

The main problem that is discussed in this article is the search for new sources of food protein. Original part of this article is economic approach to assessing the perspectives of different sources of food protein.

1. Material on using algae as the source of food protein should be added.

As suggested, a new section on algae-based sourcing has been added to the manuscript (please refer to page 2, section 2.2)

2. The methodology may be improved due to considering the influence of increases in new sources of food protein on industrial processing capacity.

This short review concentrates on the economic perspectives, key aspects of currently available technologies and challenges of alternative proteins production and market. In this revised version R1, several adjustments were made, and we hope it satisfies the reviewer’s concern.

3. The conclusions can be expanded due to discussing the problems for using algae as additional sources of food protein.

As requested, the Conclusions section was updated to reflect the addition of a new section on algae-based protein (please refer to page 10, section 4)

4. The references are appropriate.

The authors appreciate the comment from Reviewer #1. The reference list has been updated with new references for novel added information in this revised R1 version.

5. Data of tables and figures can be completed by data about algae production.

Figure 2 has been modified to reflect the new data regarding algae protein added to the manuscript, as recommended (please refer to Figure 2).

6. I suggest the authors take a closer look at algae as an alternative source of protein.

As suggested, a new section on algae-based protein has been added to the manuscript (please refer to page 4, section 2.2)

The authors thank Reviewer #1 for the insightful suggestions for improving the manuscript quality.

Reviewer 2 Report

This study focuses on “Current status and economic prospects of alternative protein

sources for the food industry”, overall quality of the paper is good, but there are still some areas that need to revise and consideration.

1. On page 2, “Food neophobia (the unwillingness to try new foods), and the sense of prejudiced... for a larger acceptance of AP”. This passage does not connect well with the later discussion of promising alternative proteins.

The organization and logic presented in the "Introduction" are found lacking.

2. On page 2, there is a discussion on increasing protein sources for aquatic plants, citing "Seagrass proteins: Sources of health-promoting agents awaiting exploration?"

3. On page 4, cultured protein also exists to generate consumer resistance, and it is recommended that the discussion be added.

4. On page 7, is “insect protein” a plant protein? Please modify.

5. On page 8, there are two “3.3”s.

6. Discussion Directions in insect and fungal protein processing technology need to be added.

Author Response

Reviewer #2

This study focuses on “Current status and economic prospects of alternative protein sources for the food industry”, overall quality of the paper is good, but there are still some areas that need to revise and consideration.

1. On page 2, “Food neophobia (the unwillingness to try new foods), and the sense of prejudiced... for a larger acceptance of AP”. This passage does not connect well with the later discussion of promising alternative proteins.

As suggested, the text has been modified to better reflect that in the manuscript (please refer to page 2). This specific passage on page 2 is intended to highlight the current and foreseen challenges of the growing alternative proteins market.

2. The organization and logic presented in the "Introduction" are found lacking.

The introduction has been totally revised to bring a more logical sequence to the text. Thanks for the suggestion.

3. On page 2, there is a discussion on increasing protein sources for aquatic plants, citing "Seagrass proteins: Sources of health-promoting agents awaiting exploration?"

Following the suggestions of Reviewers #1 and #2, a section on algae-based protein was added to the manuscript (please refer to page 4, section 2.2).

4. On page 4, cultured protein also exists to generate consumer resistance, and it is recommended that the discussion be added.

Discussion regarding the aspects associated with consumer resistance towards cultured proteins was added to the manuscript, as suggested (please refer to page 6, Section 2.4).

5. On page 7, is “insect protein” a plant protein? Please modify.

The reference to “Insect protein” previously found on page 7 was meant to be the beginning of a sub-section on insect protein, instead of a part of the plant-based protein section. The error was corrected and section 3.3 on Insect protein is now correctly numbered in the text (please refer to page 9).

6. On page 8, there are two “3.3”s.

The sections of the paper were revised and renumbered. The two sections 3.3. are now sections 3.4 Cultured meats and 3.5 Fungi proteins.

7. Discussion Directions in insect and fungal protein processing technology need to be added.

The discussion on fungi-based and insect-based protein processing has been expanded, as recommended (please refer to page 5, section 2.3 and page 7, section 2.5).

The authors gratefully appreciate the suggestions of Reviewer #2 for improving the manuscript quality.

Reviewer 3 Report

[1] Page 2: "substitute current mainstream food products" should read as "substitute for current mainstream food products".

[2] Pages 2, 6-8: The word "bi" seems to mean "billion". However, I believe that it should be replaced with "bn", for which I could find out relevant entries in the Merriam-Webster's Dictionary (https://www.merriam-webster.com/dictionary/bn) and Oxford Leaner's Dictionaries (https://www.oxfordlearnersdictionaries.com/definition/american_english/bn, https://www.oxfordlearnersdictionaries.com/definition/english/bn), while I could find out no such entries for "bi".

[3] Page 13: Specific data sources for Figures 1-3 should have been clarified by citing references, instead of simply showing a company name or homepage addresses.

[4] Page 5: The expressions, "$1.2 million US dollars" and "$50 US dollars", include both "$" and "dollars", which are collectively redundant.

[5] Page 5: "justify" in the clause, "...sawdust and branches (Okuda, 2022), justify why...", should be replaced by "justifies", and the comma can be removed without reducing its readability.

[6] Page 6: The WHO/FAO standards are mentioned here for the first time. If they are different from the FAO standards mentioned earlier, the authors should have cited appropriate references for the former standards.

[7] Page 6: The rates of increase are mentioned at the beginning of Section 3. The base and reference years should have been clarified for those rates.

[8] Page 6: The phrase, "reach to US$ 10.1 bi", should read, for example, as "reach US$ 10.1 bn".

[9] Pages 6-8: Section 3 is not well structured as follows. Subsection 3.2 "Plant-based protein" has only one sub-subsection 3.2.1 "Plant-based milk and meat substitutes", which I believe should be avoided unless there is another sub-subsection numbered 3.2.2. The third last line, "Insect protein", of page 7 should have been numbered 3.3. There are two subsections which are numbered 3.3 the same.

[10] Page 8: It might be a good idea to include the word, "fungi", in the subsection heading, "3.3 Fermentation-based proteins". This revision is expected to make Sections 2 and 3 structured in a unified and similar manner and thus improve the readability of this manuscript.

[11] Pages 9-13: The reference list seems to be separated into three parts, that is, the list includes two breaks within itself. The first break is a vertical blank on page 11 followed by Alhujaili et al. (2023). The second break is not clearly visible, but it is between You et al. (2022) and Albrecht (2021). All references should be arranged in a single list.

[12] (Continued) The style of showing publication years in the third part is different from that in the other two parts.

[13] (Continued) The three references authored by the Global Food Institute are not properly formatted. Moreover, it seems that they are not cited in the main text.

Comments [1], [2], [4], [5], and [8] provided above in the box titled "Comments and Suggestions for Authors" are related to the quality of English language.

Author Response

Reviewer #3

1. Page 2: "substitute current mainstream food products" should read as "substitute for current mainstream food products".

The correction was done, as recommended (please refer to page 2).

2. Pages 2, 6-8: The word "bi" seems to mean "billion". However, I believe that it should be replaced with "bn", for which I could find out relevant entries in the Merriam-Webster's Dictionary (https://www.merriam-webster.com/dictionary/bn) and Oxford Leaner's Dictionaries (https://www.oxfordlearnersdictionaries.com/definition/american_english/bn, https://www.oxfordlearnersdictionaries.com/definition/english/bn), while I could find out no such entries for "bi".

The abbreviation for billion was corrected to bn, as recommended (please refer to pages 2, 7-9).

3. Page 13: Specific data sources for Figures 1-3 should have been clarified by citing references, instead of simply showing a company name or homepage addresses.

The data sources for Figures 1-3 were specified and correctly identified in the reference list (please refer to page 12, reference 36; page 13, reference 43; and page 14, reference 71).

4. Page 5: The expressions, "$1.2 million US dollars" and "$50 US dollars", include both "$" and "dollars", which are collectively redundant.

The references for “US dollars” were substituted for “US$” to avoid redundancy (please refer to page 6, section 2.4).

5. Page 5: "justify" in the clause, "...sawdust and branches (Okuda, 2022), justify why...", should be replaced by "justifies", and the comma can be removed without reducing its readability.

The text was corrected, as recommended (please refer to page 7, section 2.5).

6. Page 6: The WHO/FAO standards are mentioned here for the first time. If they are different from the FAO standards mentioned earlier, the authors should have cited appropriate references for the former standards.

The FAO standards on protein and essential amino acids intakes are intended to be the same throughout the manuscript. The mentions to FAO standards were corrected in the text (please refer to page 5, section 2.3 and page 7, section 2.5) and in the reference list (please refer to page 13, reference 51).

7. Page 6: The rates of increase are mentioned at the beginning of Section 3. The base and reference years should have been clarified for those rates.

The reference years for the AP market growth rates presented in Section 3.1 are 2018-2022. That information was clarified in the text (please refer to page 8, section 3.1).

8. Page 6: The phrase, "reach to US$ 10.1 bi", should read, for example, as "reach US$ 10.1 bn".

The text was corrected, as recommended (please refer to page 8, section 3.1).

9. Pages 6-8: Section 3 is not well structured as follows. Subsection 3.2 "Plant-based protein" has only one sub-subsection 3.2.1 "Plant-based milk and meat substitutes", which I believe should be avoided unless there is another sub-subsection numbered 3.2.2. The third last line, "Insect protein", of page 7 should have been numbered 3.3. There are two subsections which are numbered 3.3 the same.

The numbering and structure of Section 3 was revised and corrected. The section separation for previous section 3.2.1 was removed, and the following sub-sections are now sections 3.3 Insect protein, 3.4 Cultured meats and 3.5 Fungi proteins (please refer to pages 8-10).

10. Page 8: It might be a good idea to include the word, "fungi", in the subsection heading, "3.3 Fermentation-based proteins". This revision is expected to make Sections 2 and 3 structured in a unified and similar manner and thus improve the readability of this manuscript.

The reading of previous section “3.3 Fermentation-based proteins” was updated for “3.5 Fungi proteins” to reflect the similar structure of sections 2 and 3, as proposed (please refer to page 10).

11. Pages 9-13: The reference list seems to be separated into three parts, that is, the list includes two breaks within itself. The first break is a vertical blank on page 11 followed by Alhujaili et al. (2023). The second break is not clearly visible, but it is between You et al. (2022) and Albrecht (2021). All references should be arranged in a single list. The style of showing publication years in the third part is different from that in the other two parts. The three references authored by the Global Food Institute are not properly formatted. Moreover, it seems that they are not cited in the main text.

The reference list was completely revised and corrected.

We thank Reviewer #3 for the thorough revision and valuable suggestions.

Round 2

Reviewer 2 Report

The revised paper reaches the level required by the journal.