Sweet Cherry Fruit Firmness Evaluation Using Compression Distance Methods

Round 1

Reviewer 1 Report (Previous Reviewer 1)

- The authors have not responded to the suggestions of the reviewer.

- The line numbers indicated in the responses do not correspond to modifications in the draft manuscript presented.

- No actual substantial modifications have been carried out. No discussion about the questions indicated by the reviewer have been addressed.

Particular comments:

-          A deep review of the texture analysis methods (and commercial devices) should be addressed. Lines 53-63 are still not enough to reference the background of the proposed study. It is necessary to justify the study with a clear literature review.

-          The objective is still not clearly defined (lines 67-69). It is clear to stablish the purpose of the study. Lines 179-182 (“In order to examine the firmness of sweet cherries, tests on two cultivars (Canada Giant and Regina) were conducted using different compression distances based on fruit size (1%, 5%, and 10%), as well as a specific compression distance of 0.16 mm in the smallest dimension of the fruit.”) seems to show the purpose of the study. However, this content is in the Result section (also part of the content that should be explained in the M & M section). Lines 213-214 (“The purpose of these tests was to assess the effectiveness of monitoring the firmness of cherries' flesh, as depicted in Figure 2ª”) also explained the purpose of the test in the Result section.

-           If the aim of the study is to demonstrate that 1% compression test is not modifying the physiological characteristics of the fruit, compared to 5% and 10% compression, this fact should be remarked.

-          The advantage of a semi-destructive method is still not defined or discussed. The authors have removed the “semi-destructive” concept. However, the final objective of the compression tests (control, 1%, 5% and 10%) should be clearly indicated. It is also crucial to define and discuss if this 1% test could be considered a non-destructive test (before the word “semi-destructive” was used by the authors)

-          The information provided by the physiological parameters, evaluated after the different compression tests, should be clearly explained and justified.

-          It is crucial to determine the usability of the proposed method for large-scale, no rigorous results are confirming this idea.

-          Figure 3 and Figure 4 results are crucial. These to Figures are demonstrating the advantage of the 1% compression test (compared to 5% and 10%). The results obtained using the 1% test are not significantly different to the control. This fact should be clearly explained and discussed. This fact needs to be carefully remarked to show the study as reliable and creditable.

Author Response

- The authors have not responded to the suggestions of the reviewer.

- The line numbers indicated in the responses do not correspond to modifications in the draft manuscript presented.

- No actual substantial modifications have been carried out. No discussion about the questions indicated by the reviewer have been addressed.

Response: Our manuscript was rejected and resubmitted after modifications such as the term ‘semi-destructive’ is not appropriate and removed. This has as a result the current manuscript reconstructed by removing related to semidestructive sentences. Hence, the changes is not clear with the red colour, because the sentences were removed.

Particular comments:

-          A deep review of the texture analysis methods (and commercial devices) should be addressed. Lines 53-63 are still not enough to reference the background of the proposed study. It is necessary to justify the study with a clear literature review.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 53-60)

-          The objective is still not clearly defined (lines 67-69). It is clear to stablish the purpose of the study. Lines 179-182 (“In order to examine the firmness of sweet cherries, tests on two cultivars (Canada Giant and Regina) were conducted using different compression distances based on fruit size (1%, 5%, and 10%), as well as a specific compression distance of 0.16 mm in the smallest dimension of the fruit.”) seems to show the purpose of the study. However, this content is in the Result section (also part of the content that should be explained in the M & M section). Lines 213-214 (“The purpose of these tests was to assess the effectiveness of monitoring the firmness of cherries' flesh, as depicted in Figure 2ª”) also explained the purpose of the test in the Result section.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 70-74)

-           If the aim of the study is to demonstrate that 1% compression test is not modifying the physiological characteristics of the fruit, compared to 5% and 10% compression, this fact should be remarked.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 67-70)

-          The advantage of a semi-destructive method is still not defined or discussed. The authors have removed the “semi-destructive” concept. However, the final objective of the compression tests (control, 1%, 5% and 10%) should be clearly indicated. It is also crucial to define and discuss if this 1% test could be considered a non-destructive test (before the word “semi-destructive” was used by the authors)

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 395-399)

-          The information provided by the physiological parameters, evaluated after the different compression tests, should be clearly explained and justified.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 338-343)

-          It is crucial to determine the usability of the proposed method for large-scale, no rigorous results are confirming this idea.

Response: Thank you for your constructive comment. In the revised manuscript large-scale application was removed.

-          Figure 3 and Figure 4 results are crucial. These to Figures are demonstrating the advantage of the 1% compression test (compared to 5% and 10%). The results obtained using the 1% test are not significantly different to the control. This fact should be clearly explained and discussed. This fact needs to be carefully remarked to show the study as reliable and creditable.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 338-343)

Reviewer 2 Report (New Reviewer)

In the introduction section, the compressed-air shock methods and acoustic methods should also be reviewed and discussed.

Author Response

In the introduction section, the compressed-air shock methods and acoustic methods should also be reviewed and discussed.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 53-57)

Reviewer 3 Report (New Reviewer)

Dear Authors,

compliments on a very well-structured and written paper.

Please consider those minor changes when revising your paper.

Line 72: please add an explanation of why those exact cultivars were chosen, is it preference, availability, or market price... Two cultivars are very few so please elaborate on this.

Please explain if this refers to the fruit thickness: 'in their small fruit dimension'. If yes, please explain and consider moving Figure 5, or some of its parts into the M&M section. It should be clear from the start, not at the end of the manuscript.

Lines 348-352 do not belong to the discussion section or should be rephrased. 

Otherwise, the manuscript is in the publishable form. 

Author Response

Dear Authors,

compliments on a very well-structured and written paper.

Please consider those minor changes when revising your paper.

Line 72: please add an explanation of why those exact cultivars were chosen, is it preference, availability, or market price... Two cultivars are very few so please elaborate on this.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 79-81)

Please explain if this refers to the fruit thickness: 'in their small fruit dimension'. If yes, please explain and consider moving Figure 5, or some of its parts into the M&M section. It should be clear from the start, not at the end of the manuscript.

Response: Thank you for your constructive comment. We revised the whole manuscript accordingly

Lines 348-352 do not belong to the discussion section or should be rephrased. 

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 363-367)

Otherwise, the manuscript is in the publishable form. 

Round 2

Reviewer 1 Report (Previous Reviewer 1)

The authors clarify the objective of the study, improved the literature review (based on the different destructive and non-destructive methods to assess firmness in cherry fruit). They have remarked the results obtained by the 1 % compression test (not significantly different to the control, and significantly different to the 5 % and 10 % compression test), specially showed in Figures 3 and 4. And focus the discussion on the non-destructive justification of the 1% test and the practical usability of the method.

The authors could include the “significant” or “no significant differences” in the comments about Figure 3. They could also remark in the conclusion section the no significant differences between control and 1% treatment in some variables. And the significant differences between control-1% and 5%-10%.

Author Response

The authors clarify the objective of the study, improved the literature review (based on the different destructive and non-destructive methods to assess firmness in cherry fruit). They have remarked the results obtained by the 1 % compression test (not significantly different to the control, and significantly different to the 5 % and 10 % compression test), specially showed in Figures 3 and 4. And focus the discussion on the non-destructive justification of the 1% test and the practical usability of the method.

The authors could include the “significant” or “no significant differences” in the comments about Figure 3. They could also remark in the conclusion section the no significant differences between control and 1% treatment in some variables. And the significant differences between control-1% and 5%-10%.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 464-467)

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

The study is based on the measurement of cherry firmness.

- The purpose of the research is not clearly defined.

- Line 11 (“…”): this sentence is confusing. How were the compression percentages assessed?

- The title of the manuscript does not define the objective of the study. The word “Monitoring” does not refer to the methodology used in the tests.

- The introduction is not clearly related to the purpose of the study. Previously developed procedures used to assess cherry firmness should be extensively review in order to justify the advantage (or the necessity) of the new proposed system.

- In the introduction, the necessity of developing a semi-destructive procedure to assess cherry firmness should be marked.

- A review of sensory quality attributes in cherry fruit should be addressed.

- The definition of “semi-destructive” should be based on previous experiments.

- The experimental design is confusing. Different measuring methods have been used but a clear explanation of the complete procedure and experimental design is missing.

- Lines 67-69: deviations (or standard error) should be added. Are these values referred to fruit quality at harvest? Are they average values from the same tested samples?

- Lines 86-88 (“In particular, fruit firmness of 100 fruit of each condition (1, 5, and 10 % fruit size and deformation forces) and cultivar was measured”) and lines 99-109  (“another 3 tests were performed for each condition (1, 5, and 10 % fruit deformation forces) and cultivar using 10 cherries for each test, as follows:”): were then 300 + 90 fruits per variety  tested (or 300+270)?

- Related to the sensory test: have the selected panelists been previously trained to test cherry attributes?

- Section 3.2. is confusing.

- Why were the samples tested using relative electrical conductivity? Why was membrane integrity of sweet cherries a reliable parameter? This measurement should be justified based on previous studies.

- Lines 178-180 (“Thereafter, a scatter plot was built between the deformation force for the specific and the size-dependent compression distance to explore the linear regression match.”: the necessity of analysing this relation should be justified.

- Figure 2.b.: A discriminant analysis (or another statistical classification method) could have been used to determine the accuracy of the firmness measurements related to the panelists classification.

- A classification of only two firmness categories seems to be very poor to be used as a reference to assess firmness. Sensory evaluation of cherry firmness should be based on many other quality attributes.

- The discussion of the results is not clearly related to the purpose of the proposed system. Some sentences (and paragraphs) are confusing (as an eample “The need for a fast and accurate firmness determination first came up due to the short window between sweet cherry handling and supply chains, and secondly, based on the applied hydro-cooling to prevent fruit senescence [30,31]” is not related to the previous eplanation a the following eplanation).

- The conclusion of the study does not effectively communicate the proposed research should be relevant to the reader once they have completed reading the paper.

Author Response

The study is based on the measurement of cherry firmness.

- The purpose of the research is not clearly defined.

Response: Thank you for the constructive comment. We revised the manuscript accordingly (Lines 8-12)

- Line 11 (“…”): this sentence is confusing. How were the compression percentages assessed?

Response: Thank you for your comment. We revised the manuscript accordingly (Lines 12-15).

- The title of the manuscript does not define the objective of the study. The word “Monitoring” does not refer to the methodology used in the tests.

Response: Thank you for your observation. We have changed the title so that it can be more accurate.

- The introduction is not clearly related to the purpose of the study. Previously developed procedures used to assess cherry firmness should be extensively review in order to justify the advantage (or the necessity) of the new proposed system.

Response: We would like to thank the Reviewer for his/her comment. We revised the introduction section accordingly (lines 52-55)

- In the introduction, the necessity of developing a semi-destructive procedure to assess cherry firmness should be marked.

Response: Thank you for your observation which improves the structure and scientific consistency of the text. We highlighted the importance in the revised manuscript (lines 61-63)

- A review of sensory quality attributes in cherry fruit should be addressed.

Response: Thank you for your comment. We understand that the term 'sensory’ does not fulfill the criteria in order to be used, so we revised it to ‘firmness assessment’ in the revised manuscript. Thus, the review of other sensory quality attributes in cherry fruit is not necessary in the present form of the manuscript.

- The definition of “semi-destructive” should be based on previous experiments.

Response: Thank you for your suggestion, however, this definition is derived from the results of the current manuscript and the impact of proposed distances in fruit physiology against destructive approaches (distance equal to 5 and 10% of the small diameter of the fruit).

- The experimental design is confusing. Different measuring methods have been used but a clear explanation of the complete procedure and experimental design is missing.

Response: We would like to thank the Reviewer for his/her constructive comment. The methods are described better in the revised manuscript, and an experimental design is also added. (Lines 79-80 and 84-85)

- Lines 67-69: deviations (or standard error) should be added. Are these values referred to fruit quality at harvest? Are they average values from the same tested samples?

Response: Thank you for your observation. SD is added, the stage of harvest is clarified in the revised manuscript and is also defined the samples. (Lines 72-75)

- Lines 86-88 (“In particular, fruit firmness of 100 fruit of each condition (1, 5, and 10 % fruit size and deformation forces) and cultivar was measured”) and lines 99-109  (“another 3 tests were performed for each condition (1, 5, and 10 % fruit deformation forces) and cultivar using 10 cherries for each test, as follows:”): were then 300 + 90 fruits per variety  tested (or 300+270)?

Response: Thank you for your observation. This point is clarified in lines 108-109 and it is 90 fruit per cultivar.

- Related to the sensory test: have the selected panelists been previously trained to test cherry attributes?

Response: Our panelists were trained only for firmness assessments. We removed sensory because our goal was not to perform a regular sensory analysis of cherry traits because we wanted to test the applied firmness methods and how accurately we could determine firmness that was previously classified by panelists assessment. In the revised manuscript remove sensory from section 2.3 and clarified our approach in lines 121-123.

- Section 3.2. is confusing.

Response: Indeed, is confusing. In the revised manuscript rewrite a large part of this section. (Lines 259-272)

- Why were the samples tested using relative electrical conductivity? Why was membrane integrity of sweet cherries a reliable parameter? This measurement should be justified based on previous studies.

Response: Thank you for your observation. Relative electrical conductivity is a parameter used for testing membrane integrity during firmness assessment. Our goal was to test if membranes are corrupted during the different deformation forces were applied. As pinpointed in the discussion section (lines 400-401) REC and damaged strawberries are positively correlated.

- Lines 178-180 (“Thereafter, a scatter plot was built between the deformation force for the specific and the size-dependent compression distance to explore the linear regression match.”: the necessity of analysing this relation should be justified.

Response: Thank you for the constructive comment. In the revised manuscript the necessity justified (Lines 188-190)

- Figure 2.b.: A discriminant analysis (or another statistical classification method) could have been used to determine the accuracy of the firmness measurements related to the panelists classification.

Response: Our purpose was to test the accuracy of applied deformation approaches (1, 5, and 10%) regarding panelists firmness assessment. So, we ask from the panelists to discriminate cherries into high and low firmness and then we measure the firmness in order to verify or reject the relevant split based on applied methodologies. We didn't have standards for compression, for example press sponge is 1 and wood is 9 based on these standards rate the cherries. Panelists simply separated fruit with high and low firmness for each cultivar separately, i.e. it was comparative and therefore not a sensory evaluation could be mentioned, forcing us to reconstruct the term ‘sensory’ into ‘firmness assessment’. Taking into account the above-mentioned we consider that our analysis is accurate.

- A classification of only two firmness categories seems to be very poor to be used as a reference to assess firmness. Sensory evaluation of cherry firmness should be based on many other quality attributes.

Response: Thank you for your observation. The current comment is answered above.

- The discussion of the results is not clearly related to the purpose of the proposed system. Some sentences (and paragraphs) are confusing (as an example “The need for a fast and accurate firmness determination first came up due to the short window between sweet cherry handling and supply chains, and secondly, based on the applied hydro-cooling to prevent fruit senescence [30,31]” is not related to the previous explanation a the following explanation).

Response: Thank you for your suggestion. We revised the manuscript accordingly (Lines 354-358)

- The conclusion of the study does not effectively communicate the proposed research should be relevant to the reader once they have completed reading the paper.

Response: Thank you for the constructive comment. We revised the manuscript accordingly (Lines 426-451)

Reviewer 2 Report

Dear Editor, it was develped a semi-destructive method for flesh firmness determination in sweet cherries and its impact on fruits’ physiological and metabolic status. The ms was well prepared and discussed. Our main comment is about the text of the Conclusion section (see attached file). After a minor revision, the ms can be considered for publication in Horticulturae.

Comments for author File: Comments.pdf

Author Response

Dear Editor, it was developed a semi-destructive method for flesh firmness determination in sweet cherries and its impact on fruits’ physiological and metabolic status. The ms was well prepared and discussed. Our main comment is about the text of the Conclusion section (see attached file). After a minor revision, the ms can be considered for publication in Horticulturae.

Response: Thank you for your constructive comment. We removed figure 5 from the conclusion and placed it to the discussion part of the manuscript.

Reviewer 3 Report

The manuscript presented by Karageorgiadou et al., presents an original investigation of Sweet cherry fruit firmness monitoring using a semi-destructive testing method.

From my point of view, the manuscript should not be accepted in its current form. In general, it is well structured in most of its sections, with the conclusion section being where it presents the greatest area of opportunity. The conclusions should not present results or images, on the contrary, they must be conclusive in the stated objectives and have the support of the results shown previously, and they must be punctual in the findings found. It is necessary to check the grammar and spelling throughout the document, as there are confusing sentences.

The following points are required to be addressed:

Avoid space between the numbers and the percentage symbol and the °C symbol (correct throughout the document). Line 128-place the unit cm-1 (superscript) correctly. Line 137, 145-change to “g” instead of “gr”.

Some sentences need to be revised to make them clearer. Review throughout the document.

Author Response

The manuscript presented by Karageorgiadou et al., presents an original investigation of Sweet cherry fruit firmness monitoring using a semi-destructive testing method.

From my point of view, the manuscript should not be accepted in its current form. In general, it is well structured in most of its sections, with the conclusion section being where it presents the greatest area of opportunity. The conclusions should not present results or images, on the contrary, they must be conclusive in the stated objectives and have the support of the results shown previously, and they must be punctual in the findings found. It is necessary to check the grammar and spelling throughout the document, as there are confusing sentences.

Response: Thank you for your constructive comments and kind words. We removed figure 5 from the conclusions. We checked the grammar and spelling throughout the manuscript.

The following points are required to be addressed:

Avoid space between the numbers and the percentage symbol and the °C symbol (correct throughout the document). Line 128-place the unit cm-1 (superscript) correctly. Line 137, 145-change to “g” instead of “gr”.

Response: Thank you for your observations. We corrected everything as proposed.

Round 2

Reviewer 1 Report

It is still necessary to clearly justify the aim of the study.

Why the normalized firmness test (deformation force, determining the required force for a distance equal to 5 or 10% of the diameter of the cherries) is not a reliable test?

Why are the advantages of the proposed system (and the substantial differences to the previous standard tests)

Lines 10-11 (“However, a firmness method involving a defined distance is quite suitable for large-scale applications. What do you mean by “large scale applications”). It has not been justified the advantage of the proposed method compared to the normalized ones related to large scale applications.

Why is the new method advantageous for large scale applications, the texture tests have been carried out using a laboratory device (Texture Analyzer). No new device has been designed; no new protocol compared to similar ones have been added. This ideas should be clearly discussed.

The information added in lines 52-55 does not justify the purpose of the study. A clear literature review should reference and help to justify the objective of the proposed study.

Why is the new method “semi-destructive” compared to the destructive standard ones? Which criteria was used to classify the proposed method used in the present study as semi-destructive?

Which is the advantage of developing a semi-destructive method? This fact is crucial, and it has not been explained in the manuscript.

Lines 61-63 (“It is of great importance that a semi-destructive protocol is established, that can provide accurate results while imitating consumer pressure applied while selecting sweet cherry fruit”), other measurement methods (and devices) have been developed to imitate consumer pressure applied while selecting the fruit. A literature review to critically compared the previous systems to the proposed one should be addressed.

Paragraph “2.3. Firmness assessment by panelist”, the experimental design is not clear.

A literature review should be addressed to confirm the validity of the proposed methos to assess firmness using seven panellists. Have the panellists been trained to assess firmness?

The definition of “semi-destructive” should be based on previous experiments.

The experimental design is still confusing. Different measuring methods have been used but a clear explanation of the complete procedure and experimental design is missing.

The explanation about why only two categories were used is still not clear. A classification of only two firmness categories seems to be very poor to be used as a reference to assess firmness. The authors said that “Our purpose was to test the accuracy of applied deformation approaches (1, 5, and 10%) regarding panelists firmness assessment. So, we ask from the panelists to discriminate cherries into high and low firmness and then we measure the firmness in order to verify or reject the relevant split based on applied methodologies. We didn't have standards for compression, for example press sponge is 1 and wood is 9 based on these standards rate the cherries”. However, the classification in two categories based on the panelist is very poor. The evaluation of cherry firmness should be based also on other parameters (colour, soluble solid content, weight loss…). Besides, a discriminant analysis (or another statistical classification method) could have been used to determine the accuracy of the firmness measurements related to the panelists classification.

The conclusions have been modified. However, they do not effectively communicate the proposed research should be relevant to the reader once they have completed reading the paper.

Author Response

It is still necessary to clearly justify the aim of the study.

Response: The aim of the study is clearly presented in lines 63-65.

Why the normalized firmness test (deformation force, determining the required force for a distance equal to 5 or 10% of the diameter of the cherries) is not a reliable test?

Response: It is reliable, but it is destructive based on our work. The results are summarized in Fig. 5.

Why are the advantages of the proposed system (and the substantial differences to the previous standard tests)

Response: The pros and cos of the proposed system are summarized in Fig. 5.

Lines 10-11 (“However, a firmness method involving a defined distance is quite suitable for large-scale applications. What do you mean by “large scale applications”). It has not been justified the advantage of the proposed method compared to the normalized ones related to large scale applications.

Response: Instead of industrial application we use the term large-scale applications. Moreover, a specific distance against varied-one has the advantage that you do not need to define the distance in varied-ones, hence, in specific distance applied one measurement less than varied-ones.

Why is the new method advantageous for large scale applications, the texture tests have been carried out using a laboratory device (Texture Analyzer). No new device has been designed; no new protocol compared to similar ones have been added. This ideas should be clearly discussed.

Response: It is not a new method, both varied and specific distance compression forces used in sweet cherry firmness determination as referred in introduction section. In this work, we study the physiological impact of these approaches in cherries and conclude that 2 of them can be used as semi-destructive and the other two as destructive. We can use even more varied and specific distances to determine its impact on firmness reliability, but this is not the scope of the current manuscript.

The information added in lines 52-55 does not justify the purpose of the study. A clear literature review should reference and help to justify the objective of the proposed study.

Response: Once again, our aim is clearly presented in lines 63-65 and it is not to develop a new approach, but to study physiological impact of these approaches (regarding firmness that already used) in cherries.

Why is the new method “semi-destructive” compared to the destructive standard ones? Which criteria was used to classify the proposed method used in the present study as semi-destructive?

Response: Physiological impact of these approaches

Which is the advantage of developing a semi-destructive method? This fact is crucial, and it has not been explained in the manuscript.

Response: The pros and cos of the proposed system are summarized in Fig. 5.

Lines 61-63 (“It is of great importance that a semi-destructive protocol is established, that can provide accurate results while imitating consumer pressure applied while selecting sweet cherry fruit”), other measurement methods (and devices) have been developed to imitate consumer pressure applied while selecting the fruit. A literature review to critically compared the previous systems to the proposed one should be addressed.

Response: We already provide both destructive and non-destructive approaches for firmness determination in the introduction section (Lines 49-60)

Paragraph “2.3. Firmness assessment by panelist”, the experimental design is not clear.

Response: We provide additional details (line 128)

A literature review should be addressed to confirm the validity of the proposed methos to assess firmness using seven panellists. Have the panellists been trained to assess firmness?

Response: Yes, they have been trained. As we already mention, ‘We didn't have standards for compression, for example press sponge is 1 and wood is 9 based on these standards rate the cherries. Panelists simply separated fruit with high and low firmness for each cultivar separately, i.e. it was comparative and therefore not a sensory evaluation could be mentioned, forcing us to reconstruct the term ‘sensory’ into ‘firmness assessment’. Taking into account the above-mentioned we consider that our analysis is accurate.’

The definition of “semi-destructive” should be based on previous experiments.

Response: We use this definition based on our results about physiological impact of these approaches in cherries and conclude that 2 of them can be used as semi-destructive and the other two as destructive. They are not ‘non-destructive’ due to the fact that physiological status of cherries affected.

The experimental design is still confusing. Different measuring methods have been used but a clear explanation of the complete procedure and experimental design is missing.

Response: The methods are described in the revised manuscript, and an experimental design is added. (Lines 72-89)

The explanation about why only two categories were used is still not clear. A classification of only two firmness categories seems to be very poor to be used as a reference to assess firmness. The authors said that “Our purpose was to test the accuracy of applied deformation approaches (1, 5, and 10%) regarding panelists firmness assessment. So, we ask from the panelists to discriminate cherries into high and low firmness and then we measure the firmness in order to verify or reject the relevant split based on applied methodologies. We didn't have standards for compression, for example press sponge is 1 and wood is 9 based on these standards rate the cherries”. However, the classification in two categories based on the panelist is very poor. The evaluation of cherry firmness should be based also on other parameters (colour, soluble solid content, weight loss…). Besides, a discriminant analysis (or another statistical classification method) could have been used to determine the accuracy of the firmness measurements related to the panelists classification.

Response: We focused on firmness, and no other parameters were evaluated. Two-class discrimination is not the applied procedure, so we remove 'sensory’ because we did not apply sensory evaluation but firmness discrimination into low and high firmness.

The conclusions have been modified. However, they do not effectively communicate the proposed research should be relevant to the reader once they have completed reading the paper.

Response: In the conclusion section we summarize our results.

In general, thank you for the constructive comment.

Round 3

Reviewer 1 Report

·         The authors clarified in their responses that the purpose of the experiment was to “study physiological impact of these approaches”. However, in lines 63 -69 (“In the present study, the development of a semi-destructive method for flesh firmness determination in sweet cherries and its impact on fruits’ physiological and metabolic status were investigated…”) the authors explained the necessity to develop a semi-destructive method. It is crucial to clearly define the objective of the study. And if one of the objectives is to develop a semi-destructive method, the advantage of this method needs to be defined.

·         A literature review still needs to be developed to address the different texture methods to measure firmness of cherry fruit.

·         If the objective of the study is to demonstrate that the method used is semi-destructive, the definition of “semi-destructive” needs to be clarified. It is very important to clearly define and justify why the results obtained about the physiological and metabolic status defined a semi-destructive method.

·         The suitability of the used method for large-scale applications still needs to be justified.

·         Figure 5 explain the pros and cons of the system. However, a clearer discussion should be added. 

Author Response

The authors clarified in their responses that the purpose of the experiment was to “study physiological impact of these approaches”. However, in lines 63 -69 (“In the present study, the development of a semi-destructive method for flesh firmness determination in sweet cherries and its impact on fruits’ physiological and metabolic status were investigated…”) the authors explained the necessity to develop a semi-destructive method. It is crucial to clearly define the objective of the study. And if one of the objectives is to develop a semi-destructive method, the advantage of this method needs to be defined.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 71-76)

• A literature review still needs to be developed to address the different texture methods to measure firmness of cherry fruit.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 55-59)

• If the objective of the study is to demonstrate that the method used is semi-destructive, the definition of “semi-destructive” needs to be clarified. It is very important to clearly define and justify why the results obtained about the physiological and metabolic status defined a semi-destructive method.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 67-69)

• The suitability of the used method for large-scale applications still needs to be justified.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 69-71)

• Figure 5 explain the pros and cons of the system. However, a clearer discussion should be added.

Response: Thank you for your constructive comment. We revised the manuscript accordingly (Lines 386-389)