Effects of Different Edible Coatings on the Shelf Life of Fresh Black Mulberry Fruits (Morus nigra L.)

Round 1

Reviewer 1 Report

The article evaluates the effect of edible coatings based on gelatin, oils (sunflower and coconut) and beeswax.

Maintaining the quality of fruit during preservation is an important research direction. The preservation quality is evaluated by assessing some physicochemical and sensory properties of Morus nigra L fruits.

The introduction is too extensive, especially as in Chapter 3. Results and discussion are shown once more certain aspects that have already been presented in Chapter 1. Introduction.

The UV-Vis method in Chapter 2, subchapter 2.3.4. UV-Vis spectroscopy of edible films and mulberry is incompletely described.

I recommend that in table 2 the functional groups that determine the absorption at the presented wavelengths be added.

The name of Figure 2 is incomplete. The article mentions table 3, which does not exist.

The subchapter 3.2 is not marked in Chapter 3. Results and discussion.

The text corresponding to lines 349-354 should be moved to Chapter 1. Introduction.

Author Response

Dear Reviewer 1,

Thanks for taking the time to review the article. Our answers are presented below.

Thank you for your suggestions that significantly improve our article.

• The introduction is too extensive, especially as in Chapter 3. Results and discussionare shown once more certain aspects that have already been presented in Chapter 1. Introduction.

The Introduction has been re-evaluated and all the changes are marked with track changing.

• The UV-Vis method in Chapter 2,subchapter 2.3.4. UV-Vis spectroscopy of edible films and mulberry is incompletely described.

The subchapter 2.3.4. has be completed.

• I recommend that in table 2 the functional groups that determine the absorption at the presented wavelengths be added.

We decided to eliminate the table because the text includes information on the UV absorption of the components in the coatings and thus avoid redundant content. In this section the information about the influence of constituents/functional groups on absorbtion peaks was included.

• The name of Figure 2 is incomplete. The article mentions table 3, which does not exist.

There was an error in writing or arranging the article for revision. The problem was solved.

• The subchapter 3.2is not marked in Chapter 3. Results and discussion.

The problem was been solved.

• The text corresponding to lines 349-354 should be moved to Chapter 1. Introduction.

We included the text in the Introduction Chapter

Author Response File: Author Response.docx

Reviewer 2 Report

I have the following comments:

1.       The last sentence of the abstract is not written correctly; it should be revised.

2.       Keywords should differ from the title, please change similar words.

3.       Line 46: the word humidity is not an adequate in the sentence.

4.       The following reference should be also included in the manuscript: Jancikova, S., Dordevic, D., Tesikova, K., Antonic, B. and Tremlova, B., 2021. Active edible films fortified with natural extracts: Case study with fresh-cut apple pieces. Membranes, 11(9), p.684.

5.       The introduction part is too long.

6.       The real picture of coatings and fruits should be added.

7.       Line 204: the method should be described more in detail.

8.       Line 207: the methods should be described more in detail too.

9.       Line 225: give the information how many females and how many males.

10.   Line 231: principal component analysis should be applied.

11.   Why statistical analysis was not applied in the Table 1? At least t-test.

12.   What is the purpose of Table 2.

13.   Figure 3: x axes should be written that they are days.

14.   The first part of Figure 4.  is not described, there should be two figures from Figure 4.

15.   Figure 7: the picture should be of better quality.

16.   Total phenol content and antioxidant activity was calculated based on the dry matter?

Author Response

Dear Reviewer 2,

Thank you for your suggestions that significantly improve our article.

Thanks for taking the time to review the article. Our answers are presented below.

 

1. The last sentence of the abstract is not written correctly; it should be revised.

The last sentence was replaced with “All edible coatings used to cover black mulberry in this study extended the shelf life of the fruits, while maintaining a high level of bioactive compounds and, consequently, a high antioxidant capacity, along with improved sensory qualities during cold storage”.

2. Keywords should differ from the title, please change similar words.

We change the keywords. We added the following: Coconut oil; sunflower oil; gelatin; beeswas; mulberry; total phenols; anthocyanins; antioxidant properties; sensorial attributes

3. Line 46: the word humidity is not an adequate in the sentence.

The word humidity was replaced with the word moisture.

4. The following reference should be also included in the manuscript: Jancikova, S., Dordevic, D., Tesikova, K., Antonic, B. and Tremlova, B., 2021. Active edible films fortified with natural extracts: Case study with fresh-cut apple pieces. Membranes, 11(9), p.684.

The article was included in the manuscript. Thank you very much for suggestion.

5. The introduction part is too long.

The introduction was reduced.

6. The real picture of coatings and fruits should be added.

We included the real picture of coatings and fruits as supplementary material (Figure S1).

7. Line 204: the method should be described more in detail.

The protocol of monomeric anthocyanins was described in more detail.

8. Line 207: the methods should be described more in detail too.

The methods of FRAP and DPPH methods were described in more details.

9. Line 225: give the information how many females and how many males.

We specified the number of males and females

10. Line 231: principal component analysis should be applied.

The PCA was performed and added in the manuscript.

11. Why statistical analysis was not applied in the Table 1? At least t-test.

We applied the statistical analysis in Table 1 (t-test).

12. What is the purpose of Table 2.

The Table 2 was removed.

13. Figure 3: x axes should be written that they are days.

We added in all the Figures, on the x-axes the word “days” to suggest that T0, T2, T5 and T8 mean the storage days.

14. The first part of Figure 4 is not described, there should be two figures from Figure 4.

We have completed the description of Figure 4, and is marked with Track Changes inside of manuscript.

We separated the Fig 4 (c ) from a and b, and now is Fig.5.

15. Figure 7: the picture should be of better quality.

We included the new Figure 7 with a better quality.

16. Total phenol content and antioxidant activity was calculated based on the dry matter?

The phenol content and antioxidant activity was calculated as fresh weight.

Author Response File: Author Response.docx

Reviewer 3 Report

 

Based on my academic judgment, there have been several studies that have investigated such topic. The manuscript has limited novelty. The introduction and discussion sections should be rewritten to address this research gap.

1) Introduction: what was the research gap of the study?

2）Methods: the methods section was not explicitly written.

 

3）Results: The results were satisfactorily written, starting with the main findings, followed by the secondary findings.

4) Discussion: lack of references to the previous study. Please compare the findings in the study with other published studies. Please discuss the main findings first, followed by the secondary findings.

5) Overall, the study lacked of novelty and the methods used had flaws.

Author Response

Reviewer 3

Thanks for taking the time to review the article. Our answers are presented below.

• Introduction: what was the research gap of the study?

As mentioned in the manuscript, the novelty of our study consist in a new approach that consists for the first time to use of protein and oil-based coatings in the case of black mulberry fruit in order to prolong the shelf life of fresh fruit, and in the same time  to maintained the interest compounds at high levels.

2）Methods: the methods section was not explicitly written.

 The methods used in manuscript were given in more details. The modifications are marked in the manuscript with Track Changes.

3）Results: The results were satisfactorily written, starting with the main findings, followed by the secondary findings.

We tried to improve the description of the results.

4) Discussion: lack of references to the previous study. Please compare the findings in the study with other published studies. Please discuss the main findings first, followed by the secondary findings.

Data from the literature, from what we know so far regarding strictly the treatments of mulberry fruits with films or coatings are very limited. I found few articles on this topic, which are mentioned in the article. This shows that there is a gap in studies to maintain the freshness of mulberries with the help of films / edible coatings of these fruits that have valuable nutritional properties.

5) Overall, the study lacked of novelty and the methods used had flaws.

In our opinion the novelty of our study is the use of edible coatings, and at the same time easily available and derived from natural resources. Our results could have a practical applicability for mulberry growers and commercial sellers.

 

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The revised manuscript has become better.

Author Response

Thank you very much for your punctual comments that really improved our manuscript.

Author Response File: Author Response.docx

Reviewer 3 Report

Although the quality of manuscript has improved, it still lacks of the critical intellectual inputs that warrant for publication as mentioned in my previous version of comments. The study is just repeating what has been reported in the literature.

Author Response

Thank you for appreciating the improvement of the manuscript.

We believe that our study brings a new approach to the use of edible coatings available to anyone from natural resources. Indeed, there are many studies on the use of fruit coatings, predominantly in strawberries, but only very few studies on mulberry fruits.

Author Response File: Author Response.docx