Color and Its Effect on Dietitians’ Food Choices: Insights from Tomato Juice Evaluation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript offers an interesting evaluation of tomato juice color measures (CIELAB color space) and its relationship with perceptions. The document flows with detailed methodological descriptions that could be improved regarding the participants' cognitive assessment.

As the authors mention in the strengths and limitations section, sample characteristics are a significant study limitation. It is unclear to what extent dietitians' color and taste assessments are similar to those of regular consumers. I suggest strengthening this argument because dietitians’ recommendations are not the main cause of tomato juice sales (line 67). The introduction could explain why or how tomato juice is usually consumed (e.g., as a meal substitute, snack, or ingredient). 

At first glance, the results appear contradictory (the more appealing, the less tasty). How is a more appealing juice (to a dietitian) less tasty? From a dietitian's perspective, a more appealing beverage should also be healthier (line 70). Thus, I'd expect the color to be less intense (if thinking about a healthy product). I recommend the literature review on healthy products by Fenko (2019); food with less saturated colors is expected to be healthier. Therefore, I recommend the authors explain the concept of “appealing” from a dietitian’s perspective. 

Likewise, participants evaluate taste as a general concept. However, dietitians may not consider a sweet taste a positive attribute. That is, regarding both cognitive variables (appeal and taste), there should be a better explanation that considers the participant's judgment. "Strenght" is another example that clarifies the idea of taste (van Rompay et al., 2016).

Another methodological procedure that should be clarified is the dependence between the two perceptual variables (lines 143-146). The ratting of taste followed the ratting of the color. However, it is unclear if participants could see the color while tasting it, or if these two evaluations were independent (presenting the stimuli in random order each time and without sight when tasting).

Suggested references:

Fenko, A. (2019). Influencing Healthy Food Choice through Multisensory Packaging Design: Designing New Product Experiences. In S. C. Velasco C. (Ed.), Multisensory Packaging (pp. 225–255). Palgrave Macmillan. https://doi.org/10.1007/978-3-319-94977-2_9

van Rompay, T. J. L., Deterink, F., & Fenko, A. (2016). Healthy package, healthy product? Effects of packaging design as a function of purchase setting. Food Quality and Preference, 53, 84–89. https://doi.org/https://doi.org/10.1016/j.foodqual.2016.06.001 

 

Author Response

Thank you so much for taking the time to evaluate our work. We have tried to incorporate all your valuable suggestions. If we could improve our work in any way, please let us know.

Comment 1.

1) As the authors mention in the strengths and limitations section, sample characteristics are a significant study limitation. It is unclear to what extent dietitians' color and taste assessments are similar to those of regular consumers. I suggest strengthening this argument because dietitians’ recommendations are not the main cause of tomato juice sales (line 67). The introduction could explain why or how tomato juice is usually consumed (e.g., as a meal substitute, snack, or ingredient).

Thank you very much for your suggestions, the introduction has been corrected.

Comment 2.

At first glance, the results appear contradictory (the more appealing, the less tasty). How is a more appealing juice (to a dietitian) less tasty? From a dietitian's perspective, a more appealing beverage should also be healthier (line 70). Thus, I'd expect the color to be less intense (if thinking about a healthy product). I recommend the literature review on healthy products by Fenko (2019); food with less saturated colors is expected to be healthier. Therefore, I recommend the authors explain the concept of “appealing” from a dietitian’s perspective.

Thank you very much for pointing out very interesting items. After reviewing them, we have added the relevant passage to the introduction of the study.

Comment 3.

Likewise, participants evaluate taste as a general concept. However, dietitians may not consider a sweet taste a positive attribute. That is, regarding both cognitive variables (appeal and taste), there should be a better explanation that considers the participant's judgment. "Strenght" is another example that clarifies the idea of taste (van Rompay et al., 2016).

Thank you very much for your comment, we have supplemented the discussion as suggested by the Reviewer.

Comment 4.

Another methodological procedure that should be clarified is the dependence between the two perceptual variables (lines 143-146). The ratting of taste followed the ratting of the color. However, it is unclear if participants could see the color while tasting it, or if these two evaluations were independent (presenting the stimuli in random order each time and without sight when tasting).

Explained in the methodology description according to the commentary.

Comment 5.

Fenko, A. (2019). Influencing Healthy Food Choice through Multisensory Packaging Design: Designing New Product Experiences. In S. C. Velasco C. (Ed.), Multisensory Packaging (pp. 225–255). Palgrave Macmillan. https://doi.org/10.1007/978-3-319-94977-2_9

van Rompay, T. J. L., Deterink, F., & Fenko, A. (2016). Healthy package, healthy product? Effects of packaging design as a function of purchase setting. Food Quality and Preference, 53, 84–89. https://doi.org/https://doi.org/10.1016/j.foodqual.2016.06.001

The indicated research items were used when improving the manuscript. Thank you.

Thank you for your help. Your guidance is invaluable.

Kind regards,

Authors.

Reviewer 2 Report

Comments and Suggestions for Authors

Hi dear Editorial board and the respected authors

This article "Color and Its Effect on Dietitians' Food Choices: Insights from Tomato Juice Evaluation” was revised and has a novelty and I recommend it for publication after consideration of the following comments.

The study investigates the impact of color on dietitian food preferences using tomato juices. Dietitians were chosen as the study population due to their sensitivity to color perception. The color of the juices was evaluated using a Tri-Color SF80 spectrophotometer. Not all tested pairs had noticeable color differences, suggesting that human visual perception is sensitivity.

There was no clear correlation between specific color parameters and dietitians' choices. The abstract suggests that other factors beyond color might have influenced dietitians' preferences for tomato juices. This finding has implications for product marketing strategies, particularly in the food industry. Companies must balance the importance of color with other product attributes to effectively appeal to their target consumers. The findings could provide insights into how to balance the importance of color with other product attributes in the food industry.

Abstract:

·         According to the abstract, the study attempted to evaluate the influence of color on dietician meal choices by using tomato juice as an example. Why were dietitians selected as the research population? What is the significance of understanding color preferences among this specific group?

·         According to the abstract, the color of tomato juices was measured using a Tri-Color SF80 spectrophotometer. Can you elaborate on the particular color metrics or features that were measured with this instrument? How were the color variations among the juices quantified?

·         According to the abstract, not all of the examined juice combinations displayed color changes that would be evident to a "inexperienced observer". What does this say about the sensitivity of human visual perception in relation to the instrumental color?

·         According to the abstract, there was no apparent association between the precise color factors and dietitians' selections. Can you hypothesize on what other variables, other from color, may have impacted the dietitians' preferences for tomato juice? What more insights may be gleaned from investigating these other possible factors?

·         The abstract finds that, while color is essential in customer preferences, it is not the only determinant. What is the significance of this discovery for product marketing efforts, particularly in the food industry? How can businesses effectively appeal to their target audiences by balancing the importance of color with other product attributes?

·         Keywords: Please choose keywords other than the main words of the title. In this case, other researchers can find your article by searching a wide range of words through databases.

 

Materials:

·                       Please write materials as Company Name (City, Country), especially for chemical analysis assessment which used in the study.

Methodology:

·         Some methods do not have references. Please cite Food Science and Technology 42, e60820 “for Line 111-124.

“Results:

·         All Tables and figures: The alphabetical statistical letters for the means should all be modified such that the greatest number has the letter a and as the numbers go lower, letters b, c etc.

·         All of the Figures and Tables ought to provide as self-explanatory.

·         Few studies have concentrated solely on determining the color of tomato juice, with greater emphasis on the nutritional content and health advantages of tomatoes.
According to recent studies, color has a considerable impact on customer choices and perceptions of food goods. Consumers like brighter, more crimson colors that represent ripeness, sweetness, and quality.

·         The red color of tomato juice indicates not just freshness and quality, but also the presence of lycopene, a valuable antioxidant. This dual relevance emphasizes the role of color in both sensory perception and health-related characteristics.

·         Previous research employed spectrophotometric techniques to assess the color characteristics (lightness, redness, and yellowness) of various tomato juice products. The results demonstrate variances in hue, even amongst juices.

·         Consumer preference surveys have revealed that the deepest, reddest, and least yellow tomato juices are often considered as the best in flavor, even if they are not the brightest or most physically pleasing.

·         Color variations in food goods can indicate quality changes during storage, and color influences customer perception and acceptance of food products.

Discussion:

·         Discussion text must grammar improve and in some cases it is very weak and maybe there is no discussion at all.

Strengths and limitations

·         The research study has limitations, including sampling bias, homogeneity of the sample, and subjectivity of sensory evaluations. The sample was limited to female dietetics students, which may not be representative of the broader dietitian population. The participants had similar ages and educational backgrounds, which may not reflect the experiences of dietitians with more varied backgrounds. Sensory tests used in the study rely on subjective human assessments, which can introduce personal biases and preferences, limiting the objectivity of the results. Future studies should recruit a more diverse and representative sample of dietitians to increase the generalizability of the findings.

Conclusions:

·         Conclusion is very general, try to make it more scientific, comprehensive and concise in detail, especially.

·         The study reveals that color perception significantly influences dieters' ratings of tomato juices. The least attractive juice received high ratings for flavor, suggesting color and flavor preferences may differ. Dieters may prefer natural-looking products, even if less intense in color. The study partially confirms the relationship between color intensity and shade and dieters' preferences. However, other factors like composition or production method may also influence ratings. This study highlights the complex dynamics between visual perception and food product evaluation.

References: It is OK.

The article has many flaws in express and concept of English, it is suggested to be revised in a scientific and native way.

Please utilize the new reference in the manuscript text as the following:

Heidari M, Khodadadi Jokar Y, Madani S, Shahi S, Shahi MS, Goli M. Influence of Food Type on Human Psychological-Behavioral Responses and Crime Reduction. Nutrients. 2023 Aug 25;15(17):3715. doi: 10.3390/nu15173715. PMID: 37686747; PMCID: PMC10490081.

 

Comments on the Quality of English Language

The article has many flaws in express and concept of English, it is suggested to be revised in a scientific and native way.

 

 

Author Response

Response to Reviewer 3

Thank you so much for taking the time to evaluate our work. We have tried to incorporate all your valuable suggestions. If we could improve our work in any way, please let us know.

Comment 1.

According to the abstract, the study attempted to evaluate the influence of color on dietician meal choices by using tomato juice as an example. Why were dietitians selected as the research population? What is the significance of understanding color preferences among this specific group?

Described in lines 53-57.

Comment 2.

According to the abstract, the color of tomato juices was measured using a Tri-Color SF80 spectrophotometer. Can you elaborate on the particular color metrics or features that were measured with this instrument? How were the color variations among the juices quantified?

Described in lines 156-158.

Comment 3.

According to the abstract, not all of the examined juice combinations displayed color changes that would be evident to a "inexperienced observer". What does this say about the sensitivity of human visual perception in relation to the instrumental color?

The study highlighted that while spectrophotometric analysis can detect minute differences in color, these differences are not always perceptible to the human eye, particularly for inexperienced observers​​. This suggests that human visual perception is less sensitive than instrumental methods like the CIELAB color system, which can quantify small changes in color with high precision.

The findings indicate that the ΔE values between some juice pairs were discernible only by experienced observers or not at all by the human eye, despite being measurable instrumentally. This demonstrates that human visual perception, particularly among those without training, may not be reliable for detecting subtle color variations that could be critical for quality control in food products. Therefore, while human perception is crucial for consumer preferences and market acceptance, instrumental measurements are essential for ensuring consistency and quality in food production.

An appropriate description has been added to the results.

Comment 4.

According to the abstract, there was no apparent association between the precise color factors and dietitians' selections. Can you hypothesize on what other variables, other from color, may have impacted the dietitians' preferences for tomato juice? What more insights may be gleaned from investigating these other possible factors?

Thank you for the comment. In response to the reviewer's remark, it can be hypothesized that various other factors besides color may have influenced dietitians' preferences for tomato juice, such as taste, texture, aroma, and processing method. Dietitians might prefer fresher juices, which could result from differences in processing methods (e.g., pasteurization, concentrates) that affect taste and nutritional value. Additionally, personal preferences and previous experiences can shape dietitians' choices. The context in which the juice is consumed may also impact preferences, for instance, as a breakfast beverage, cocktail ingredient, or food accompaniment.

Comment 5.

The abstract finds that, while color is essential in customer preferences, it is not the only determinant. What is the significance of this discovery for product marketing efforts, particularly in the food industry? How can businesses effectively appeal to their target audiences by balancing the importance of color with other product attributes?

84-104 described.

Comment 6.

Keywords: Please choose keywords other than the main words of the title. In this case, other researchers can find your article by searching a wide range of words through databases.

Corrected as suggested.

Comment 7.

Please write materials as Company Name (City, Country), especially for chemical analysis assessment which used in the study.

Corrected as suggested.

Comment 8.

Some methods do not have references. Please cite Food Science and Technology 42, e60820 “for Line 111-124.

Please point out the specific citation you think is appropriate...

Comment 9.

All Tables and figures: The alphabetical statistical letters for the means should all be modified such that the greatest number has the letter a and as the numbers go lower, letters b, c etc..

Please clarify your comment, I don't know how I am supposed to correct the averages in the tables.

Comment 10.

All of the Figures and Tables ought to provide as self-explanatory..

All Tables and Figures are clear.

Comment 11.

  Discussion text must grammar improve and in some cases it is very weak and maybe there is no discussion at all.

Corrected the entire discussion grammatically.

Comment 12.

The research study has limitations, including sampling bias, homogeneity of the sample, and subjectivity of sensory evaluations. The sample was limited to female dietetics students, which may not be representative of the broader dietitian population. The participants had similar ages and educational backgrounds, which may not reflect the experiences of dietitians with more varied backgrounds. Sensory tests used in the study rely on subjective human assessments, which can introduce personal biases and preferences, limiting the objectivity of the results. Future studies should recruit a more diverse and representative sample of dietitians to increase the generalizability of the findings.

The indicated passage was added.

Comment 13.

Conclusion is very general, try to make it more scientific, comprehensive and concise in detail, especially..

Corrected.

Comment 14.

Please utilize the new reference in the manuscript text as the following:

Heidari M, Khodadadi Jokar Y, Madani S, Shahi S, Shahi MS, Goli M. Influence of Food Type on Human Psychological-Behavioral Responses and Crime Reduction. Nutrients. 2023 Aug 25;15(17):3715. doi: 10.3390/nu15173715. PMID: 37686747; PMCID: PMC10490081...

Added as suggested.

Thank you very much for your valuable suggestions.

Kind regards,

Authors.

Reviewer 3 Report

Comments and Suggestions for Authors

The 3.1 heading "3.1 Instrumental color analysis of orange juice by  spectrophotometric ..." leads the reader initially to think that you are not dealing with tomato juice but orange juice. You have an earlier study (which you cite) in which you looked at orange juice preferences and have reused some of the technical language. I have no problem with this, but you should go back over the text to be sure that there are no other similar typographic errors. For example, in that section, you also refer to a juice by an incorrect name (HF) when it appears as HT in your tables.

I enjoyed reading this paper. I especially enjoyed the results and discussion which were quite interesting. The dietitians had color and taste preferences, but those two did not interact significantly. I guess we should not be surprised that the old adage against judging a book by its cover still rings true.

Author Response

Thank you so much for taking the time to evaluate our work. We have tried to incorporate all your valuable suggestions. If we could improve our work in any way, please let us know.

Comment 1.

The 3.1 heading "3.1 Instrumental color analysis of orange juice by  spectrophotometric ..." leads the reader initially to think that you are not dealing with tomato juice but orange juice. You have an earlier study (which you cite) in which you looked at orange juice preferences and have reused some of the technical language. I have no problem with this, but you should go back over the text to be sure that there are no other similar typographic errors. For example, in that section, you also refer to a juice by an incorrect name (HF) when it appears as HT in your tables.

The entire manuskrupt was checked to eliminate confusion. Thank you very much for noticing our oversight.

Thank you for your help. Your guidance is invaluable.

Kind regards,

Authors.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

By examining the revised article by the respected authors, it seems that the quality of the article has reached a higher level of scientific approach, and in my opinion, it is capable of being published in the journal.