Impact of Pure, Co-, and Sequential Fermentations with Hanseniaspora sp. and Saccharomyces cerevisiae on the Volatile Compounds of Ciders

Round 1

Reviewer 1 Report

Review

Novelty: Is the question original and well-defined? Do the results provide an advancement of the current knowledge?

Yes, Non-Saccharomyces used in cider fermentation is a noval topic

Scope: Does the work fit the journal scope*?

Yes, it is so

Significance: Are the results interpreted appropriately? Are they significant? Are all conclusions justified and supported by the results? Are hypotheses carefully identified as such?

Yes, no standard deviations are drawn in the graphics. Please decribe the results more in details.

Quality: Is the article written in an appropriate way? Are the data and analyses presented appropriately? Are the highest standards for presentation of the results used?

It should be overworked. Eg. Standard derivation should be inculded in the graphis and please enter the number of repetitions

Scientific Soundness: Is the study correctly designed and technically sound? Are the analyses performed with the highest technical standards? Is the data robust enough to draw conclusions? Are the methods, tools, software, and reagents described with sufficient details to allow another researcher to reproduce the results? Is the raw data available and correct (where applicable)?

The study and the technical instruments are ok, but I can not find the amount of repitation of the samples. The sample volume of 1200ml ist very small. Therefore, only limited conclusions can be drawn about the practical applications.

Interest to the Readers: Are the conclusions interesting for the readership of the journal? Will the paper attract a wide readership, or be of interest only to a limited number of people? (Please see the Aims and Scope of the journal.)

This datas are very interseting for researcher und practitioner.

Overall Merit: Is there an overall benefit to publishing this work? Does the work advance the current knowledge? Do the authors address an important long-standing question with smart experiments? Do the authors present a negative result of a valid scientific hypothesis?

Yes, it is advance for the current knowledge.

English Level: Is the English language appropriate and understandable?

It is a very nice English and  good to understand.

Author Response

Manuscript ID: fermentation -2910081

Title: Impact of Pure, Co-, and Sequential Fermentations with Hanseniaspora sp and Saccharomyces cerevisiae on the Volatile Compounds of Ciders

Dear Dr. Ms. Katrina Xu

Fermentation

Thank you for your response to our manuscript fermentation-2910081.

The constructive criticism of the reviewers was much appreciated and we revised our manuscript accordingly. All suggestions were accepted. More information and details were included in the text, and the manuscript was revised thoroughly. All the modifications performed in the revised manuscript are highlighted. The accompanying document at the bottom of this letter contains a point-to-point reply to the reviewer.

Thank you in advance for your attention.

 Reviewer # 1

Question 1: Is the question original and well-defined? Do the results provide an advancement of the current knowledge?

Reviewer 1: Yes, Non-Saccharomyces used in cider fermentation is a noval topic

Answer: Thank you for your comments.

Question 2: Scope: Does the work fit the journal scope*?

Reviewer 1: Yes, it is so

Answer: Thank you for your comments.

Question 3: Significance: Are the results interpreted appropriately? Are they significant? Are all conclusions justified and supported by the results? Are hypotheses carefully identified as such?

Reviewer 1: Yes, no standard deviations are drawn in the graphics. Please describe the results more in detail.

Answer: Thank you for your comments. The suggestion was accepted and changes were performed accordingly. Please check the information in the text and Figure 2. Adding a standard deviation to Figure 1 would pollute the graphs and make it difficult to see the results.

Question 4: Quality: Is the article written in an appropriate way? Are the data and analyses presented appropriately? Are the highest standards for presentation of the results used?

 Reviewer 1: It should be overworked. Eg. Standard derivation should be included in the graphics and please enter the number of repetitions

Answer: Thank you for your comments. The suggestion was accepted and changes were performed accordingly. Please check the information in the text and graphics. Adding a standard deviation to Figure 1 would pollute the graphs and make it difficult to see the results.

Question 5: Scientific Soundness: Is the study correctly designed and technically sound? Are the analyses performed with the highest technical standards? Is the data robust enough to draw conclusions? Are the methods, tools, software, and reagents described with sufficient details to allow another researcher to reproduce the results? Is the raw data available and correct (where applicable)?

Reviewer 6: The study and the technical instruments are ok, but I cannot find the amount of repetition of the samples. The sample volume of 1200mL is very small. Therefore, only limited conclusions can be drawn about the practical applications.

Answer: Thank you for your comments. The experiments were carried out in triplicate. Please check the information in the text.

Question 6: Interest to the Readers: Are the conclusions interesting for the readership of the journal? Will the paper attract a wide readership, or be of interest only to a limited number of people? (Please see the Aims and Scope of the journal.)

Reviewer 1: This data is very interesting for researchers and practitioners.

Answer: Thank you for your comments.

Question 7: Overall Merit: Is there an overall benefit to publishing this work? Does the work advance the current knowledge? Do the authors address an important long-standing question with smart experiments? Do the authors present a negative result of a valid scientific hypothesis?

Reviewer 7: Yes, it is advanced for the current knowledge.

Answer: Thank you for your comments.

Question 8: English Level: Is the English language appropriate and understandable?

Reviewer 1: It is a very nice English and good to understand.

Answer: Thank you for your comments.

We think we were able to respond adequately to all issues raised by the reviewer and hope you will find our manuscript now acceptable for publication in Fermentation. If any further modifications are necessary, please inform us, and we will make every effort to implement them.

On behalf of all authors,

Yours sincerely,

Prof. Alessandro Nogueira,

State University of Ponta Grossa

Reviewer 2 Report

The work submitted for review is interesting and well-written. The errors noted are listed below:

Page 2, line 88:

Please correct the names of chemical compounds:

3-methyl ethyl butanoate -> ethyl 3-methylbutanoate (?)

2-methyl propyl ethanoate -> 2-methylpropyl ethanoate

3-methyl butyl ethanoate  -> 3-methylbutyl ethanoate 

2-hydroxy ethyl propanoate -> 2-hydroxyethyl propanoate

2-phenyl-ethanol ->  2-phenylethanol

Page 2, line 98:

… apple must (?)

Page 2, line 101:

Why was the enzyme preparation added to the must and not to the crushed fruit?

Page 3, 148

Standardize the units of ethanol concentration throughout the work:

% vol, °GL, % (Page 6, line 217-220; Table 1)

Page 3, line 256

Heptanoic acid -> heptanoic acid

Only heptanoic acid was used as an internal standard? Acid is not an optimal internal standard when determining esters, alcohols or aldehydes. This decision could have significantly influenced the results obtained.

Page 4, line 160

 The name and model of the gas chromatograph, detector type, column used and chromatographic separation parameters were not provided.

Page 4, line 170

The name and model of HPLC, detector type and chromatographic separation parameters were not provided.

Page 6, line 219

Please explain the inaccuracy in the sentence:

„higher ethanol yields” or  „higher ethanol concentration/content”

Page 6, line 217-220

The concentration of ethanol is traditionally given in % vol.

Page 6, line 228

The sentence is imprecise.

“The nitrogen”  ->  “Total Kjeldahl nitrogen”

Page 7, Note in Table 1

gCO2/L/d  ->  CO₂ g/L/d;

Page 8, line 276 and Fig 2.A

From the text it appears that Fig 2.A was prepared as the sum of identified and unidentified compounds. In my opinion, this is a substantive error because the concentration of unidentified compounds cannot be provided. For obvious reasons, their response factors are not known. The chart should be corrected and refer to the sum of the identified compounds.

Page 9, Table 2

2-hydroxy ethyl propanoate -> 2-hydroxyethyl propanoate

2-phenyl ethanol -> 2-phenylethanol

 Please check: “1,4-ethyl butanoate” (?)

Author Response

Manuscript ID: fermentation -2910081

Title: Impact of Pure, Co-, and Sequential Fermentations with Hanseniaspora sp and Saccharomyces cerevisiae on the Volatile Compounds of Ciders

Dear Dr. Ms. Katrina Xu

Fermentation

Thank you for your response to our manuscript fermentation-2910081.

The constructive criticism of the reviewers was much appreciated and we revised our manuscript accordingly. All suggestions were accepted. More information and details were included in the text, and the manuscript was revised thoroughly. All the modifications performed in the revised manuscript are highlighted. The accompanying document at the bottom of this letter contains a point-to-point reply to the reviewer.

Thank you in advance for your attention.

Reviewer # 2

Reviewer 2: The work submitted for review is interesting and well-written. The errors noted are listed below:

Answer: Thank you for your comments.

Reviewer 2: Page 2, line 88:

Please correct the names of chemical compounds:

3-methyl ethyl butanoate -> ethyl 3-methylbutanoate (?)

2-methyl propyl ethanoate -> 2-methylpropyl ethanoate

3-methyl butyl ethanoate -> 3-methylbutyl ethanoate

2-hydroxy ethyl propanoate -> 2-hydroxyethyl propanoate

2-phenyl-ethanol -> 2-phenylethanol

Answer: Thank you for your comments. The suggestion was accepted and changes were performed accordingly. Please check the information in the text and table.

Reviewer 2: Page 2, line 98:

… apple must (?)

Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 2, line 101:

Why was the enzyme preparation added to the must and not to the crushed fruit?

Answer: Thank you for your comment. The use of the pectinase enzyme was for the apple juice depectinization, as a pre-clarification treatment. In this research, the application of maceration/liquefaction enzymes to the crushed apple was not one of the objectives.

Reviewer 2: Page 3, 148

Standardize the units of ethanol concentration throughout the work:

% vol, °GL, % (Page 6, line 217-220; Table 1)

Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 3, line 256

Heptanoic acid -> heptanoic acid

Only heptanoic acid was used as an internal standard? Acid is not an optimal internal standard when determining esters, alcohols or aldehydes. This decision could have significantly influenced the results obtained.

Answer: Thank you for your comment. The method was revised and 4-methyl-1-amyl alcohol was used as an internal standard with heptanoic acid.

Reviewer 2: Page 4, line 160

The name and model of the gas chromatograph, detector type, column used, and chromatographic separation parameters were not provided.

Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 4, line 170

The name and model of HPLC, detector type and chromatographic separation parameters were not provided.

Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 6, line 219

Please explain the inaccuracy in the sentence:

„higher ethanol yields” or higher ethanol concentration/content”

 Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 6, line 217-220

The concentration of ethanol is traditionally given in % vol.

Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 6, line 228

The sentence is imprecise.

“The nitrogen”  ->  “Total Kjeldahl nitrogen”

Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 7, Note in Table 1

gCO2/L/d  ->  CO₂ g/L/d;

 Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

Reviewer 2: Page 8, line 276 and Fig 2.A

From the text it appears that Fig 2.A was prepared as the sum of identified and unidentified compounds. In my opinion, this is a substantive error because the concentration of unidentified compounds cannot be provided. For obvious reasons, their response factors are not known. The chart should be corrected and refer to the sum of the identified compounds.

 Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly.

Reviewer 2: Page 9, Table 2

2-hydroxy ethyl propanoate -> 2-hydroxyethyl propanoate

2-phenyl ethanol -> 2-phenylethanol

 Please check: “1,4-ethyl butanoate” (?)

 Answer: Thank you for your comment. The suggestion was accepted and changes were performed accordingly. Please check the information in the text

We think we were able to respond adequately to all issues raised by the reviewer and hope you will find our manuscript now acceptable for publication in Fermentation. If any further modifications are necessary, please inform us, and we will make every effort to implement them.

On behalf of all authors,

Yours sincerely,

Prof. Alessandro Nogueira,

State University of Ponta Grossa

Round 2

Reviewer 1 Report