Buprestid Beetles of Togo: Ecological, Sociocultural, and Nutritional Impacts of a High Quality Food Source

Round 1

Reviewer 1 Report (Previous Reviewer 1)

Comments and Suggestions for Authors

This paper is a throrough investigation of edible beetle culture in Togo, combining interviews with specimen collection and ID plus nutritional analysis. It's a very impressive piece of work.

The paper is similalry well written. It has clearly stated objectives and a concise introduction. The methods are clear and detailed. Everything is quite thorough. The results are mostly clear. The discussion puts everything into context well.

I am satisfied with the sample size of the surveying and of the chemical analyses.

I'm a bit consued by Table 2. What is the n of people surveyed? Does the 10% with the 9 5-30 year olds in Anoufo, for example, mean 10% of the surveyed people are in that agre group, or 10% of the surveyed people in that age group eat insects, implying the total n was 90? 
Please replace "Generations (ages in years)" with "Ages in Years ([whatever the number in parenthesis represents])". The heading of the column should match the formatting of what is inside the column. 

339 How did you differentiate between marginalization and deculturation in the interview?

Table 5 is not cited in the text at all. I think it can be replaced with a sentence listing the ratios instead of a full table. "Sodium/potassium, calcium/phosphorus, and calcium/magnesium ratios for S. interrrupta are 0.03, 1.08, and 2.00 respectively."

The English level is high and no major English editing is needed

Author Response

 

Our responses to the comments of Reviewer 1:

We thank this reviewer for his/her generally very positive comments. Regarding Table 2, the percentages have been calculated in relation to the number of 90 people surveyed in each group. The heading of the Table has been adjusted to reflect this more clearly.

Regarding differentiation between marginalization and deculturation we have now written: “Marginalization through a lack of opportunities(18%) and deculturation expressed as an alienation from traditions (14%) additionally play a significant role.”

Table 5 was not cited in the text at all, but it is now, together with the sentence "Sodium/potassium, calcium/phosphorus, and calcium/magnesium ratios for S. interrrupta are 0.03, 1.08, and 2.00 respectively." (Lines 363 & 364)

 

 

 

Reviewer 2 Report (New Reviewer)

Comments and Suggestions for Authors

Line 20:  The first "health" in that line should be removed.

Line 53: Change "by" to "as"

Lin 176 and 177:  This method is not correct for the determination of the protein content of chitin containing substances.  The nitrogen in the chitin will result in a severe overestimation of the protein content.  Using BC for the determination of intact protein would be a more suitable option.  Else the constant factor of 6.25 must be adapted to reflect the fact that it is used for insects.  The value of 5.33 is generally regarded as representative for edible insects.

Line 319:  Although very nice data you never mention that you are looking at this.  Add something about this in the materials and methods

Line 347 & 348 and Table 3:  The protein content noted should be adjusted.  Also keep in mind that the insects do not really contain fiber and that the fiber which was analyzed will be an indication of the chitin content of the insects.  The energy value would then also be overestimated.

Line 499:  Ensure that comparisons are made on equal footing.  So check which conversion factor was used for the protein determination.

Line 60:  The fiber analyzed would not be dietary fiber but in fact a portion of the chitin of the exoskeleton.  This can thus not be concluded.  The presence of chitin in large quantities could reduce digestibility and decrease mineral availability.

 

 

 

Author Response

Our responses to the comments of Reviewer 2:

We thank the reviewer for his/her insightful comments and now point out in the text that the method used to determine the protein content of chitin tends to overestimate  the protein content. We have added this information: “The factor represents a nitrogen content of animal protein generally, but conversion factors for edible insect proteins (although variable) are somewhat lower and an average of 5.33 for edible insects has been suggested [25]. Therefore, our values are likely an overestimation of the protein content, but comparable to earlier insect studies that had also used a conversion factor of 6.25.”

In connection with Table 3, we added “The protein content could be an overestimation (see section 2.3) and fibre, as is the case with most other edible insects, would largely be the portion of the chitin in the exo-skeleton.”

On Line 505, we now state: “Based on comparisons with insects in which the protein content was determined as in this paper, S. interrupta can be regarded an important source of animal protein.”

The last paragraph of the Discussion now reads: “The fibre content of the studied species is higher than that of conventional meat products [26], although the fibre in insects would be a portion of their exoskeleton. Nonetheless, the buprestid species investigated by us supports healthy digestion for individuals of all ages since it is known that dietary fibre, irrespective of whether de-rived from insect chitin or not, can improve gut health [60]. In addition, fibre has a positive effect on enhancing satiety, thereby reducing the risk of overeating and obesity [61]. Finally, it must not be dismissed that a certain proportion of humans possess in their gastric juice enzymes that can digest insect chitin [62].

In the Conclusion we now state “Although chitin can act as an antinutrient and negatively affect the uptake of minerals, e.g., iron [63] and some antinutrients, such as tannin and phytic acid, may exist in small amounts, as they do in other insects (e.g., Odontotermes sp. and O. smaragdina [33]), they can be ignored as the balance of essential amino acids, fatty acids, and variety of minerals in S. interrupta renders this species highly nutritious. Moreover, as the authors Mwangi et al. [63] of their 2022 paper conclude: “Our study was of an exploratory nature and therefore needs further confirmation by future studies.”

 

Reviewer 3 Report (Previous Reviewer 2)

Comments and Suggestions for Authors

The manuscript submitted by Badanaro and Meyer-Rochow, entitled "Buprestid Beetles of Togo: Ecological, Sociocultural, and Nutritional Impacts of a High Quality Food Source" discusses a survey of edible beetle consumption in an ecological zone of Togo, West Africa. In addition to surveying the prevalence of consumption of three species of buprestids among different age groups and seven different ethnic groups, the study also analysed the proximate composition of one of the species (Sternocera interrupta) consumed by the inhabitants of this region. The analytical techniques used to determine the insect's composition are well-established and appear to have been well-executed in this study. The data show that these beetles are a rich source of nutrients, such as proteins, vitamins, minerals, and fatty acids, both saturated and unsaturated.

The authors did a good job on the second version of the manuscript. I believe my suggestions were taken into account and I think the manuscript can be published in its current form.

Author Response

Our responses to the comments of Reviewer 3:

We thank the reviewer for his/her positive comments and this reviewer’s conclusion that “the manuscript can be published in its current form.” Great, Thank you!

 

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper examines edible Buprestid beetles. I had heard of these but read little about them, so this is a needed addition to the literature. The authors do a terrific job of combining surveys of people with taxonomic and nutritional analyses of the food insects. 

Overall it's a great paper. I have only one request: more methods information on the survey. Can you please share a copy of these questions as a supplementary data sheet? [I understand they may be in the local language, but either this and/or an English translation would be very useful.]

Author Response

We would like to express our sincere gratitude for your comments and suggestions.

 

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript submitted by Badanaro and Meyer-Rochow, entitled "Consumption of Buprestid Beetles in Togo: Ecological, Sociocultural, and Nutritional Impacts," discusses a survey of edible beetle consumption in an ecological zone of Togo, West Africa. In addition to surveying the prevalence of consumption of three species of buprestid beetles among different age and seven different ethnic groups, the study also analysed the proximate composition of one of the species (Sternocera interrupta) consumed by the inhabitants of this region. The analytical techniques used to determine the insect's composition are well-established and appear to have been well-executed in this study. The data show that these beetles are a rich source of nutrients, such as proteins, vitamins, minerals, and fatty acids, both saturated and unsaturated. The only essential amino acid found in concentrations below the recommended optimum was tryptophan. The work provides interesting information, such as the difference in beetle consumption preferences between young and older members, with young people showing the least interest in consuming the insects as food, with no difference in this pattern among the ethnic groups evaluated. Another important finding is the decline in consumption of these edible beetle species in Togo over time.

The work is simple but addresses an important topic: food security and entomophagy. There are some errors throughout the text, which can be easily corrected. Below, I list some necessary changes for the manuscript to be accepted for publication:

1- I suggest using the L for liter throughout the text. In some passages, such as lines 156, 159, 213, 215, 218, 219, and 221, ml was used.

2- Line 303 – What does the abbreviation SPSS stand for?

3- Table 1 shows the genus Hydaticus, but the species cited is from another genus. Please correct this.

4- Line 463: Correct the order of the species Gryllus maculatus. It is not Coleoptera, but Orthoptera.

One more question: Why was only one species used to determine the proximate nutritional composition? What criteria were used to select this species and not the other two?

Author Response

The reason we chose to study the nutritional composition of S. interrupta is that it is the most frequently encountered species in the study area. We mentioned this in Specific Objective 3. Thank you very much for your comments and suggestions. We truly appreciate the time and effort you put into reviewing our manuscript, which has significantly contributed to its improvement."

The reason we chose to study the nutritional composition of Sternocera interrupta is that it is the most frequently encountered species in the study area. We mentioned this in Specific Objective 3. Thank you so much for your comments and suggestions. We truly appreciate the time and effort you put into reviewing our manuscript, which has significantly contributed to its improvement.