Effect of Tea Polyphenols on Curdlan/Chitosan Blending Film Properties and Its Application to Chilled Meat Preservation
Round 1
Reviewer 1 Report
This paper is focused on the preparation, characterization, and testing of the curdlan/chitosan/tea polyphenol composite films as a coating for the preservation of chilled meat. In general, the topic is suitable for Coatings. However, it seems that the manuscript needs some significant improvements before its publication. I recommend "major revisions" instead of "reject", but with the caveat that the authors have a lot of work to do to reach an acceptable manuscript.
Major points:
1. Line 79: The curdlan sample must be characterized by its molecular weight (MW).Provide also the method (with appropriate references) used to determine MW of curdlan.
2. Line 86: Provide the concentrations of both curdlan and chitosan stock solutions.
3. Line 94: Provide the thickness of the composite films.
4. Table 1: The standard deviation should be expressed as ONE significant figure; that is, unless the number is between 11 and 19 times some power of ten, in which case you can use two significant figures. The mean value should be rounded off at the decimal place corresponding to the last significant digit of its standard deviation. E.g., 14.9 ± 0.67 should be presented as 14.9 ± 0.7 and 40.0 ± 0.16 should be presented as 40.0X ± 0.16 (X – add one more significant figure).
5. Tables 1 and 2: a,b,c,d notations are not clear. Please revise the notations so that they are clear to the readers.
6. Section 3.1.2: It would be desirable to add the experiments on the swelling and/or solubility of composite films.
7. Line 252: What do you mean by ‘many tea polyphenols aggregated’?
8. Line 263: The statement ‘total colony number of each treatment group increased with time’ contradicts with data the data shown in Table 2.
9. Line 275: What does the reference value of 106 CFU/g indicate, given that the value of 5.805 CFU/g (line 276) is 'close to the spoilage meat'?
10. Line 276: I do not see any value of 5.805 CFU/g for L.1 group in Table 2. Please revise thoroughly Section 3.2.1 to clarify the discussion of your results.
11. Lines 282 and 291: Please clarify which value is the reference for TVB-N - 15 or 20 mg/100 g.
12. Quality of Figure 3 must be improved; it is hardly visible. Please add the reference line for TVB-N (Figure 3a).
13. There are too many English errors and wrong constructions, which sometimes drastic affect the scientific meaning, making the paper difficult of reading and understanding. A native English speaker with a scientific background should carefully revise the manuscript prior to its resubmission.
Minor points:
1. Line 26: Remove (PVC) – this acronym is not used again.
2. Line 42: ‘viscosity’ (high or low?) is not a special feature of chitosan.
3. Line 43: Consider citing here the recent reviews on chitosan properties and application (Poshina et al. Polymer Degradation and Stability, 2018, 156, 269-278 DOI: 10.1016/j.polymdegradstab.2018.09.005; Kritchenkov et al., Russ Chem Rev, 2017, 86, 231–239, DOI: 10.1070/RCR4636).
4. Line 73: Add ‘, chitosan’ after ‘curdlan’.
5. Line 87: Replace ‘pending liquid’ to ‘solutions’.
6. Line 137: Provide a reference for equation (4).
7. Line 206: Replace ‘standard ± deviation deviation’ to ‘mean ± standard deviation’.
8. Line 206: Remove (SD) – this acronym is not used again.
9. Lines 217 and 355: Replace ‘CD/CS’ to ‘curdlan/chitosan’. You did not introduce these acronyms in the text.
10. Line 244: Figure 1 legend is missed.
11. Section 2.3.3. and 3.1.3: You mix the use of DPPH acronym to denote both chemical compound (1,1-Diphenyl-2-1picrylhydrazyl) and free radical scavenging activity (Equation 4 and Figure 1). Consider introducing two different acronyms.
12. Line 269: Replace ‘bacteriostasis’ to ‘bacteriostatic’.
13. Table 2: What is meant by ‘evaluation project’? Change the table legend to a more appropriate one. Replace PH, L*, a*, and b* to pH, lightness L*, red degree a*, and yellow degree b*, respectively.
14. Line 355: Replace ‘polysaccharide / chitosan’ to ‘curdlan/chitosan’
15. Line 358: Incomplete sentence.
16. Correct the author’s name in Reference [14].
Author Response
Dear Editor,
We are truly grateful for you and the reviewer’s critical comments and thoughtful suggestions on our manuscript which entitled “Effects of tea polyphenols on the properties of curdlan/chitosan blending film and its application in chilled meat preservation”. We feel lucky that our manuscript went to you and the other reviewer as the valuable comments helped us with the improvement of our manuscript. Based on these comments and suggestions, we have made careful modification on the original manuscript. Our point-by-point responses are attached below. We hope the new manuscript will meet your magazine’s standard.
We are willing to do any further revision if required. Thank you very much for your kindness.
Yours sincerely,
Chong Zhang, Ph. D
College of Food Science and Technology,
Nanjing Agricultural University,
Nanjing 210095, Jiangsu, People’s Republic of China
E-mail: [email protected]
Response to Reviewer #1
Major points:
Q1: Line 79: The curdlan sample must be characterized by its molecular weight (MW).Provide also the method (with appropriate references) used to determine MW of curdlan.
Response: The curdlan' molecular weight has been written.
Q2: Line 86: Provide the concentrations of both curdlan and chitosan stock solutions.
Response: The concentration of the solution is already indicated.
Q3: Line 94: Provide the thickness of the composite films.
Response: The thickness of the film needs to be measured, so the accurate value cannot be provided
Q4: Table 1: The standard deviation should be expressed as ONE significant figure; that is, unless the number is between 11 and 19 times some power of ten, in which case you can use two significant figures. The mean value should be rounded off at the decimal place corresponding to the last significant digit of its standard deviation. E.g., 14.9 ± 0.67 should be presented as 14.9 ± 0.7 and 40.0 ± 0.16 should be presented as 40.0X ± 0.16 (X – add one more significant figure).
Response: The numerical representation has been modified.
Q5: Tables 1 and 2: a,b,c,d notations are not clear. Please revise the notations so that they are clear to the readers.
Response: The remarks have been added.
Q6: Section 3.1.2: It would be desirable to add the experiments on the swelling and/or solubility of composite films.
Response: This indicator is not measured, so there is no way to provide this indicator as data.
Q7: Line 252: What do you mean by ‘many tea polyphenols aggregated’?
Response: As the content of tea polyphenols increases, some molecules of tea polyphenols aggregate with each other, resulting in rough surface of the film.
Q8: Line 263: The statement ‘total colony number of each treatment group increased with time’ contradicts with data the data shown in Table 2.
Response: The horizontal and vertical rows have been inverted and have now been corrected.
Q9: Line 275: What does the reference value of 106 CFU/g indicate, given that the value of 5.805 CFU/g (line 276) is 'close to the spoilage meat'?
Response: This value(106 CFU/g) is the reference value in the national standard. 5.805 CFU/g is wrong and has been corrected.
Q10: Line 276: I do not see any value of 5.805 CFU/g for L.1 group in Table 2. Please revise thoroughly Section 3.2.1 to clarify the discussion of your results.
Response: The data writing error in the discussion has been corrected.
Q11: Lines 282 and 291: Please clarify which value is the reference for TVB-N - 15 or 20 mg/100 g.
Response: 15mg/100 g.
Q12: Quality of Figure 3 must be improved; it is hardly visible. Please add the reference line for TVB-N (Figure 3a).
Response: The picture definition has been modified.
Q13: There are too many English errors and wrong constructions, which sometimes drastic affect the scientific meaning, making the paper difficult of reading and understanding. A native English speaker with a scientific background should carefully revise the manuscript prior to its resubmission.
Response: The language of the article has been polished.
Minor points:
Q1: Line 26: Remove (PVC) – this acronym is not used again.
Response: This acronym has been removed.
Q2: Line 42: ‘viscosity’ (high or low?) is not a special feature of chitosan.
Response: This part, the feature of chitosan, has been removed.
Q3: Line 43: Consider citing here the recent reviews on chitosan properties and application (Poshina et al. Polymer Degradation and Stability, 2018, 156, 269-278 DOI: 10.1016/j.polymdegradstab.2018.09.005; Kritchenkov et al., Russ Chem Rev, 2017, 86, 231–239, DOI: 10.1070/RCR4636).
Response: A reference about chitosan has been added.
Q4: Line 73: Add ‘, chitosan’ after ‘curdlan’.
Response: Yes, This part has been corrected.
Q5: Line 87: Replace ‘pending liquid’ to ‘solutions’.
Response: Yes, This part has been corrected.
Q6: Line 137: Provide a reference for equation (4).
Response: There has been added a references.
Q7: Line 206: Replace ‘standard ± deviation deviation’ to ‘mean ± standard deviation’.
Response: Yes, this part has been modified.
Q8: Line 206: Remove (SD) – this acronym is not used again.
Response: Yes, this part has been modified.
Q9: Lines 217 and 355: Replace ‘CD/CS’ to ‘curdlan/chitosan’. You did not introduce these acronyms in the text.
Response: Yes, this part has been modified.
Q10: Line 244: Figure 1 legend is missed.
Response: Yes, I have added this legend.
Q11: Section 2.3.3. and 3.1.3: You mix the use of DPPH acronym to denote both chemical compound (1,1-Diphenyl-2-1picrylhydrazyl) and free radical scavenging activity (Equation 4 and Figure 1). Consider introducing two different acronyms.
Response: Yes, I have unified these acronym.
Q12: Line 269: Replace ‘bacteriostasis’ to ‘bacteriostatic’.
Response: Yes, this part has been modified.
Q13: Table 2: What is meant by ‘evaluation project’? Change the table legend to a more appropriate one. Replace PH, L*, a*, and b* to pH, lightness L*, red degree a*, and yellow degree b*, respectively.
Response: Evaluation project include pH, color, TBARS, TVB-N, etc. The table legend has been modified.
Q14: Line 355: Replace ‘polysaccharide / chitosan’ to ‘curdlan/chitosan’
Response: Yes, this part has been modified.
Q15: Line 358: Incomplete sentence.
Response: Yes, I have completed the sentence.
Q16: Correct the author’s name in Reference [14]
Response: Yes, this part has been modified.
Reviewer 2 Report
The paper provide an valuable and interesting information concerning the chosen properties of edible films and their impact on the chilled meat preservation. However, the manuscript requires an extensive editing of English language and its style. Furthermore manuscript needs a lot of work of precising the details, explanation all of the abbreviations used in the text and in the tables, expanding the discussion based on literature data. Below I put my comments and suggestions:
2.2. Film preparation
Which reagent was used to adjust pH to 4-5? If the climating chamber were used to dry the films in controlled condition? Please be more precise, what does it mean that samples were conditioned at a “controlled temp and RH”?
2.3.1. The precision of the thickness measurements was…?
Explain all the abbreviations in the equations.
2.3.3. The formulation “time sampling…” is not clear. Give the time of samples incubation in the dark.
2.4.1. Incorporation of tea polyphenols was calculated and expressed on the 1 g of dry mass of films component or on the 100 g of polymeric solution?
3.1.1. It is unclear, how the tea polyphenols may destroyed a polymer network of the films, and caused the decrease in TS. Explain the phenomenon based on the literature data.
Table 1. In Reviewer opinion there is no changes in TS, WVP and WC% values after incorporation of 0.6 and 3.0% of tea polyphenols. The values did not differ significantly. It is not explained why the results increase/decrease from 0.6% to 1.8%, and then the impact is opposite between 1.8% and 3% of tea polyphenols addition. There is a mistake in the Table, there should be MC% not WC%. How it is possible that the values of EB: 20.8 and 6.01 did not differ significantly? (the same small letter “c”). The parameters WVP and MC% are completely not discussed with comparison to the literature data. It is unclear what the Authors mean, that “… trace tea polyphenols can produce obvious effect”.
3.1.3 line 233 what does it mean “gussed”? Explain also what does it mean “novel polymeric antioxidants”.
Fig 3.1.4. Add the units in the Figure.
3.2.1. Lines 259-262. The same sentence was written twice. Explain the abbreviations in this chapter and in the Table 2. In the Table 2 should be pH not PH. Explain why the L* value at day 3 for L1 increase from 34.52 to 54.51 and then decreased to 34.02?
Chapters 3.2.4 and 3.2.5. should be described chronologically as the parameters in the Table 2.
3.2.5. It is not obvious, how the polyphenols may release from the sample L0 which was the sample without incorporation of tea polyphenols. The whole description of the L*, a* and b* values of the cold fresh meat is opposite to that the Authors reported.
Reference 27 should not be written by capital letters.
Author Response
Dear Editor,
We are truly grateful for you and the reviewer’s critical comments and thoughtful suggestions on our manuscript which entitled “Effects of tea polyphenols on the properties of curdlan/chitosan blending film and its application in chilled meat preservation”. We feel lucky that our manuscript went to you and the other reviewer as the valuable comments helped us with the improvement of our manuscript. Based on these comments and suggestions, we have made careful modification on the original manuscript. Our point-by-point responses are attached below. We hope the new manuscript will meet your magazine’s standard.
We are willing to do any further revision if required. Thank you very much for your kindness.
Yours sincerely,
Chong Zhang, Ph. D
College of Food Science and Technology,
Nanjing Agricultural University,
Nanjing 210095, Jiangsu, People’s Republic of China
E-mail: [email protected]
Response to Reviewer #2
Q1: 2.2. Film preparation
Which reagent was used to adjust pH to 4-5? If the climating chamber were used to dry the films in controlled condition? Please be more precise, what does it mean that samples were conditioned at a “controlled temp and RH”?
Response:①We adjust the pH with acetic acid and sodium hydroxide.
②No, we use the constant temperature and humidity cabinet to control the environmental conditions.
Q2: 2.3.1. The precision of the thickness measurements was…?
Explain all the abbreviations in the equations.
Response:①The precision of the thickness measurements was 0.01mm.
②I've added the explanation of the formula.
Q3: 2.3.3. The formulation “time sampling…” is not clear. Give the time of samples incubation in the dark.
Response: ①This part's expression is error, and I have corrected in the article.
②The time of samples incubation in the dark is 1h.
Q4: 2.4.1. Incorporation of tea polyphenols was calculated and expressed on the 1 g of dry mass of films component or on the 100 g of polymeric solution?
Response: The tea polyphenols was expressed on the 1 g of dry mass of films component.
Q5: 3.1.1. It is unclear, how the tea polyphenols may destroyed a polymer network of the films, and caused the decrease in TS. Explain the phenomenon based on the literature data.
Response: The explanation of this part has been added in the article.
Q6: Table 1. In Reviewer opinion there is no changes in TS, WVP and WC% values after incorporation of 0.6 and 3.0% of tea polyphenols. The values did not differ significantly. It is not explained why the results increase/decrease from 0.6% to 1.8%, and then the impact is opposite between 1.8% and 3% of tea polyphenols addition. There is a mistake in the Table, there should be MC% not WC%. How it is possible that the values of EB: 20.8 and 6.01 did not differ significantly? (the same small letter “c”). The parameters WVP and MC% are completely not discussed with comparison to the literature data. It is unclear what the Authors mean, that “… trace tea polyphenols can produce obvious effect”.
Response: ①After incorporation of 0.6% and 3.0% of tea polyphenols，the TS, WVP and WC% values of films have changed in the value, but it's a small change.
②I have explained the reason about the opposite phenomenon.
③The mistake in the table has been modified.
④Mistakes were made in copying the data.
⑤I have added the discussion about WVP and MC%.
⑥The meaning of this sentence has been explained in the passage.
Q7: 3.1.3 line 233 what does it mean “gussed”? Explain also what does it mean “novel polymeric antioxidants”.
Response:①What I'm trying to say is that the word arised.
②Chitosan-phenolic acid complex is a relatively new polymer with antioxidant properties.
Q8: Fig 3.1.4. Add the units in the Figure.
Response: Yes, I have added the units in the figure.
Q9: 3.2.1. Lines 259-262. The same sentence was written twice. Explain the abbreviations in this chapter and in the Table 2. In the Table 2 should be pH not PH. Explain why the L* value at day 3 for L1 increase from 34.52 to 54.51 and then decreased to 34.02?
Response:①I have deleted the repeated sentences.
②Yes, the explanation of the abbreviations have been added.
③Yes, the clerical error has been corrected.
④I have corrected the data error，and the data should be compared horizontally.
Q10: Chapters 3.2.4 and 3.2.5. should be described chronologically as the parameters in the Table 2.
Response: This part is described in the order on the table.
Q11: 3.2.5. It is not obvious, how the polyphenols may release from the sample L0 which was the sample without incorporation of tea polyphenols. The whole description of the L*, a* and b* values of the cold fresh meat is opposite to that the Authors reported.
Response:①No grafted tea polyphenols were naturally volatilized from the sample.
②L.0 is the sample without incorporation of tea polyphenols.
③Yes, this part has been modified.
Q12: Reference 27 should not be written by capital letters.
Response: The imported references are written in the format required by the article, that is, in capitals.
Reviewer 3 Report
The subject matter is potentially useful to readers of Coatings, however the manuscript should be strongly revised before publication. The topic of the manuscript is interesting and the used methodology is appropriate, however the way of presentation and language is not acceptable. Some of the points are included below, nevertheless the main point is to extensively review the manuscript (a lot of typos, not correctly written sentences, repetitions, not scientific launguage used in some part of the article) for article improvement which seems to be interesting for Coatings readers. The following suggested major changes should be considered:
Abstract:
- Line 22: Some properties of the composite film were improved
Abstract should be more precised and without general statements
Materials and methods:
2.2. Film preparation:
- Line 92: To control the film thickness, the volume of each film-forming solution was fixed
Please, provide the volume of film-forming solution
2.4. Application in the preservation of chilled meat
2.4.1. Packing chilled meat with the blending film
- Line 148:
Please provide what kind of meat was used - which part of pork muscle (as pork was mentioned later in the manuscript)
- Table with details of 5 groups will be more readable (suggestion)
- What was the blank control? Fresh meat?
- Lines 152- 153: it was mentioned that the samples were stored for 20 days. In the results section Authors only provided information (results) until day 9th.
- Line 153-154: The samples were measured every two days until the end of storage
What exactly was measured?
2.4.2. Antibacterial activity analysis
- Please, specify used bacterial strains and what was the reason of choosen such bacteria in the research.
- How antimicrobial analysis with pathogens was performed? Was meat incubated with certain amount of bacteria? If yes, what was the initial concentration? Where are the results with pathogens?
Results and discussion
- Page 7: Please add Fig.1 to DPPH graph
3.1.4. Scanning electron microscopy (SEM) analysis
- 3.1.4 should be on the left of the page
- Line 252: At the same time, there are many tea polyphenols aggregated in the composite film
Where it is shown in the picture?
- Page 10: Figure 3 – poor quality of graphs
3.2. Application in chilled meat preservation
3.2.1. Microbial assay
- Lines 264-266:
Compared with the Control group and the L.0 group, the total colony total of treatment groups of L.1, L.2 and L.3 decreased obviously, and there was no significant difference between the three groups during the whole storage period (P > 0.05)
I do not understand
- Page 8 Table 2
· How was established statistical significance of the group? (i sit shown between verses or between columns?)
· The results should be reflected as a log reduction (with the initial value of fresh meat sample)
- Line 275: The total number of colonies of the other three treatment groups was not more than 106 CFU/g at the end of the storage time, but the total number of colony in the L.1 group was 5.805, close to the spoilage meat
It is mentioned about the results which are not in the table
General comments to the Results and Discussion sections: Lack/not enough discussion and comparison with other studies in sections:
- 3.1.4 Scanning electron microscopy (SEM) analysis
- 3.2.2. TVB-N
- 3.2.3. TBARS
- 3.2.4. pH
Author Response
Dear Editor,
We are truly grateful for you and the reviewer’s critical comments and thoughtful suggestions on our manuscript which entitled “Effects of tea polyphenols on the properties of curdlan/chitosan blending film and its application in chilled meat preservation”. We feel lucky that our manuscript went to you and the other reviewer as the valuable comments helped us with the improvement of our manuscript. Based on these comments and suggestions, we have made careful modification on the original manuscript. Our point-by-point responses are attached below. We hope the new manuscript will meet your magazine’s standard.
We are willing to do any further revision if required. Thank you very much for your kindness.
Yours sincerely,
Chong Zhang, Ph. D
College of Food Science and Technology,
Nanjing Agricultural University,
Nanjing 210095, Jiangsu, People’s Republic of China
E-mail: [email protected]
Round 2
Reviewer 1 Report
The authors have successfully addressed most of the reviewers’ concerns, improving the manuscript with their edits. However, there are still several points for authors to consider:
1. line 87: Add what ‘certain amounts’ of the curdlan and chitosan solutions were mixed.
2. Line 95-96: I do not understand what do you mean by ‘The film thickness was measured using a vernier caliper, and there is no specific value.’ Ether add a specific value (range of values) of the film thickness or remove this sentence.
3. Table 2: The standard deviation should be expressed as ONE significant figure; that is unless the number is between 11 and 19 times some power of ten, in which case you can use two significant figures. The mean value should be rounded off at the decimal place corresponding to the last significant digit of its standard deviation. Please, make corrections for all values!
4. Line 290: Replace ‘the total colony number’ to ‘the logarithm of the total colony number’.
5. Line 294: Either remove ‘was 5.25, which was’ or add ‘the logarithm of’ the total colony number.
6. Line 294-295: Move the sentence ‘The logarithm of the total colony number had reached 6, which proved that the meat had spoiled.’ earlier to line 292.
7. Table 3: Replace ‘Evaluation project’ to ‘Parameter’
8. Table 3: Replace ‘total bacterial counts (CFU/g) Data processing error’ to ‘logarithm of the total colony number’.
9. Line 298: Move heading 3.2.2 to the next row.
10. Figure 3b: Add a reference line at 1.0 mg MAD/kg (according to Chinese Standard GB-9959.2-2008)
11. Line 373: It is bizarre that the polymer ratio in composite films appears in Conclusion for the first time. Please indicate whether this is a mass or molar ratio and reflect this information in the Experimental (section 2.2).
12. English usage is often poor. Please check the paper once again to clarify meaning, improve awkward sentence structure and correct grammar.
Author Response
Dear Editor,
We are truly grateful for you and the reviewer’s critical comments and thoughtful suggestions on our manuscript which entitled “Effects of tea polyphenols on the properties of curdlan/chitosan blending film and its application in chilled meat preservation”. We feel lucky that our manuscript went to you and the other reviewer as the valuable comments helped us with the improvement of our manuscript. Based on these comments and suggestions, we have made careful modification on the original manuscript. Our point-by-point responses are attached below. We hope the new manuscript will meet your magazine’s standard.
We are willing to do any further revision if required. Thank you very much for your kindness.
Yours sincerely,
Chong Zhang, Ph. D
College of Food Science and Technology,
Nanjing Agricultural University,
Nanjing 210095, Jiangsu, People’s Republic of China
E-mail: [email protected]
Response to Reviewer #1
Q1: line 87: Add what ‘certain amounts’ of the curdlan and chitosan solutions were mixed.
Response: Yes, this part has been added in the article.
Q2: Line 95-96: I do not understand what do you mean by ‘The film thickness was measured using a vernier caliper, and there is no specific value.’ Ether add a specific value (range of values) of the film thickness or remove this sentence.
Response: Sorry, I did not express clearly before, now I have corrected this part.
Q3: Table 2: The standard deviation should be expressed as ONE significant figure; that is unless the number is between 11 and 19 times some power of ten, in which case you can use two significant figures. The mean value should be rounded off at the decimal place corresponding to the last significant digit of its standard deviation. Please, make corrections for all values!
Response: Yes, I have modified this table.
Q4: Line 290: Replace ‘the total colony number’ to ‘the logarithm of the total colony number’.
Response: Yes, I have modified this part.
Q5: Line 294: Either remove ‘was 5.25, which was’ or add ‘the logarithm of’ the total colony number.
Response: Yes, I have modified this part.
Q6:Line 294-295: Move the sentence ‘The logarithm of the total colony number had reached 6, which proved that the meat had spoiled.’ earlier to line 292.
Response: Yes, I have modified this part.
Q7: Table 3: Replace ‘Evaluation project’ to ‘Parameter’
Response: Yes, I have modified this part.
Q8:Table 3: Replace ‘total bacterial counts (CFU/g) Data processing error’ to ‘logarithm of the total colony number’.
Response: Yes, I have modified this part.
Q9: Line 298: Move heading 3.2.2 to the next row.
Response: Yes, I have modified this part.
Q10: Figure 3b: Add a reference line at 1.0 mg MAD/kg (according to Chinese Standard GB-9959.2-2008)
Response: Yes, I have modified this part.
Q11: Line 373: It is bizarre that the polymer ratio in composite films appears in Conclusion for the first time. Please indicate whether this is a mass or molar ratio and reflect this information in the Experimental (section 2.2).
Response: I supplemented the experimental method in the section 2.2, and the ratio between curdlan and chitosan was the mass ratio.
Q12: English usage is often poor. Please check the paper once again to clarify meaning, improve awkward sentence structure and correct grammar.
Response: Yes, I have modified some of the statements in the article.
Reviewer 2 Report
none
Author Response
Dear Reviewer,
We are truly grateful for you and the reviewer’s critical comments and thoughtful suggestions on our manuscript which entitled “Effects of tea polyphenols on the properties of curdlan/chitosan blending film and its application in chilled meat preservation”. We feel lucky that our manuscript went to you and the other reviewer as the valuable comments helped us with the improvement of our manuscript. Thank you.
Yours sincerely,
Chong Zhang, Ph. D
College of Food Science and Technology,
Nanjing Agricultural University,
Nanjing 210095, Jiangsu, People’s Republic of China
E-mail: [email protected]
Reviewer 3 Report
I recommend the acceptance od the current version of the manuscript.
Author Response
Dear Reviewer,
We are truly grateful for you and the reviewer’s critical comments and thoughtful suggestions on our manuscript which entitled “Effects of tea polyphenols on the properties of curdlan/chitosan blending film and its application in chilled meat preservation”. We feel lucky that our manuscript went to you and the other reviewer as the valuable comments helped us with the improvement of our manuscript. Thank you.
Yours sincerely,
Chong Zhang, Ph. D
College of Food Science and Technology,
Nanjing Agricultural University,
Nanjing 210095, Jiangsu, People’s Republic of China
E-mail: [email protected]
Response to Reviewer #3
Q1:Abstract:
- Line 22: Some properties of the composite film were improved
Abstract should be more precised and without general statements
Response: I have added some specific properties of the film.
Materials and methods: 2.2. Film preparation:
Q2:- Line 92: To control the film thickness, the volume of each film-forming solution was fixed
Please, provide the volume of film-forming solution
Response: Yes, the volume of film-forming solution is 100mL.
2.4. Application in the preservation of chilled meat
2.4.1. Packing chilled meat with the blending film
Q3:- Line 148:
Please provide what kind of meat was used - which part of pork muscle (as pork was mentioned later in the manuscript)
Response: The meat we used was black pork tenderloin.
Q4:- Table with details of 5 groups will be more readable (suggestion)
Response: Yes , I've tabulated the groups.
Q5:- What was the blank control? Fresh meat?
Response: The blank control is cold fresh meat without films.
Q6:- Lines 152- 153: it was mentioned that the samples were stored for 20 days. In the results section Authors only provided information (results) until day 9th.
Response: Sorry, there is a clerical error here.
Q7:- Line 153-154: The samples were measured every two days until the end of storage， What exactly was measured?
Response: We measured the color, pH, colony counts, TBARS and TVB-N of samples.
2.4.2. Antibacterial activity analysis
Q8:- Please, specify used bacterial strains and what was the reason of choosen such bacteria in the research.
Response: Yes, this part has been added in the article.
Q9:- How antimicrobial analysis with pathogens was performed? Was meat incubated with certain amount of bacteria? If yes, what was the initial concentration? Where are the results with pathogens?
Response:①The bacteriostasis was analyzed by plate counting method.
②No, meat itself contains a certain amount of bacteria. The result is expressed as the total bacterial counts. Results and discussion
Q10:- Page 7: Please add Fig.1 to DPPH graph
Response: Yes , we have added it.
3.1.4. Scanning electron microscopy (SEM) analysis
Q11:- 3.1.4 should be on the left of the page
Response: Yes, this part has been modified.
Q12:- Line 252: At the same time, there are many tea polyphenols aggregated in the composite film ，Where it is shown in the picture?
Response: The small particles in the figure are formed by the aggregation of some tea polyphenols, and the remaining tea polyphenols may bind to curdlan or chitosan.
Q13:- Page 10: Figure 3 – poor quality of graphs
Response: Yes, this part has been modified.
3.2. Application in chilled meat preservation
3.2.1. Microbial assay
Q14:- Lines 264-266:
Compared with the Control group and the L.0 group, the total colony total of treatment groups of L.1, L.2 and L.3 decreased obviously, and there was no significant difference between the three groups during the whole storage period (P > 0.05)。 I do not understand
Response: The expression of this part is wrong, and this part has been modified in the article.
Q15:- Page 8 Table 2
How was established statistical significance of the group? ( sit shown between verses or between columns?)
Response: It sit shown between verses.
Q16:The results should be reflected as a log reduction (with the initial value of fresh meat sample)
Response: All data is collected from the first day, and there is no initial value, so there is no way to reflect it as a log reduction.
Q17:- Line 275: The total number of colonies of the other three treatment groups was not more than 106 CFU/g at the end of the storage time, but the total number of colony in the L.1 group was 5.805, close to the spoilage meat
It is mentioned about the results which are not in the table
Response: Sorry, there is a clerical error here.
Q18:General comments to the Results and Discussion sections: Lack/not enough discussion and comparison with other studies in sections:
- 3.1.4 Scanning electron microscopy (SEM) analysis
- 3.2.2. TVB-N
- 3.2.3. TBARS
- 3.2.4. pH
Response: Yes, I have supplemented the discussion on these indicators.
