Environmental and Economic Analysis of the Production of Oregano Oil Microparticles

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript “Environmental and economic analysis of the production of oregano oil microparticles” presents important objectives by carrying out an analysis considering various economic and environmental factors in the production of oregano essential oil microparticles, looking for more advantageous processes, with less impact, which is a current demand of industries around the world.

Below are my contributions:

- How were the encapsulants (modified starch, gum arabic and maltodextrin) chosen for the microencapsulation of oregano essential oil? Was the choice of encapsulants based solely on the literature or were preliminary tests carried out to confirm their effectiveness?

- Did the reuse of water in the steam distillation process have any impact on the quality of the extracted essential oil?

- What were the reasons for choosing the distillation time? Was there any significant variation in the composition of the essential oil with shorter or longer distillation times?

- What were the main environmental factors considered when assessing the environmental impact of the microencapsulation process?

- Did the economic analysis only consider direct operating costs or did it also include factors such as product stability and other costs?

- Did the microparticles produced with different encapsulants show significant variations in their properties, such as density?

- Considering the growing demand for sustainable processes, what would be the next steps to further optimize the microencapsulation process of oregano essential oil?

- Are there any plans to expand this research to other essential oils? Which oils would be the most promising?

- What challenges can the authors foresee in the transition from the laboratory microencapsulation process to an industrial scale?

- How would stabilizing production costs on smaller quantities of processed oregano leaves impact economic viability on a large scale?

 

Author Response

Reviewer(s)' Comments to Author:

The authors would like to thank the Editor and Reviewers for allowing the opportunity to improve the quality of the manuscript. The Reviewers made significant comments and raised some queries, which during the writing process had passed unnoticed, demonstrating their dedication to the revision process. The revised version of the manuscript addresses all relevant comments and suggestions made by the Reviewers. All changes made in the manuscript are presented in the files named "Manuscript_rev", while an additional document entitled "Supporting Information_rev" was prepared with supporting data.

Below is the reply to the Reviewers' comments to support the decisions that the authors took in the revision process of this work.

Reviewer: 1

Comments:

The manuscript “Environmental and economic analysis of the production of oregano oil microparticles” presents important objectives by carrying out an analysis considering various economic and environmental factors in the production of oregano essential oil microparticles, looking for more advantageous processes, with less impact, which is a current demand of industries around the world.

Below are my contributions:

- How were the encapsulants (modified starch, gum arabic and maltodextrin) chosen for the microencapsulation of oregano essential oil? Was the choice of encapsulants based solely on the literature or were preliminary tests carried out to confirm their effectiveness?

Author: The selection of encapsulants was guided by the literature and preliminary tests based on the methodology described by Hijo et al. (2017): Understanding the Influence of Encapsulating Matrix on the Physical and Thermal Properties of Oregano Essential Oil. To clarify this for the reader, a sentence was added to section 2.2.

 "The choice of encapsulants was based on the methodology described by Hijo et al. [38] especially considering the wide applications of this oil in different sectors of industry, such as food, pharmaceuticals and cosmetics.”

- Did the reuse of water in the steam distillation process have any impact on the quality of the extracted essential oil?

Author: The methodology applied in the oil extraction process allows the water to be reused in the process. However, the yield of the oil obtained was sufficient for this study. Therefore, the quality of the extracted essential oil was not evaluated with reused water.

- What were the reasons for choosing the distillation time? Was there any significant variation in the composition of the essential oil with shorter or longer distillation times?

Author: The maximum yield of oregano essential oil in short distillation times was the reason for choosing the distillation time. There was no significant variation in the composition of the essential oil with shorter or longer distillation times.

- What were the main environmental factors considered when assessing the environmental impact of the microencapsulation process?

Author: The main environmental factor that is the major contributor to the microencapsulation impacts is electricity consumption in Brazil, as stated in the previous version of the manuscript, Pg. 9, lines 307-308, and Table 1. The electricity mix of Brazil is mainly based on renewable energy from hydropower (more than 60%), biofuel, wind and solar (around 25%), and in a lesser proportion generated by fossil fuels such as natural gas, hard coal and fuel oil (less than 10%) and nuclear (less than 5%). With electricity mix sources, the depletion of hard coal, fuel oil and natural gas for electricity generation is the main contributor to the environmental impacts of electricity generation used during microencapsulation.

- Did the economic analysis only consider direct operating costs or did it also include factors such as product stability and other costs?

Author: The economic analysis presented in this work considered only costs associated with the production process. Other costs that are outside the production, such as product stability, distribution, packaging, storage, etc. were not included.

- Did the microparticles produced with different encapsulants show significant variations in their properties, such as density?

Author: The particle density was not evaluated in this study. However, it is inferred that the variation of different encapsulants can alter the properties of the powder obtained considering the proportion used and the distinct physical characteristics of each material.

- Considering the growing demand for sustainable processes, what would be the next steps to further optimize the microencapsulation process of oregano essential oil?

Author: The next steps to optimize the microencapsulation process of oregano essential oil would involve evaluating the stability and quality of microparticles produced by spray drying to improve production. To make this clear to the reader, we have added the following sentence to the conclusion:

“Research on the stability and quality of microparticles by spray drying should be further investigated; however, recent studies show trends to improve production such as the use of different encapsulation methods, variation in operational conditions and the influence of new encapsulants.”

- Are there any plans to expand this research to other essential oils? Which oils would be the most promising?

Author: The promising oils to be evaluated are essential and non-essential, such as tamarind seed oil, passion fruit seed oil, pequi oil, buriti oil, and Brazil nut oil. Work is in progress.

- What challenges can the authors foresee in the transition from the laboratory microencapsulation process to an industrial scale?

Author: The choice of the technologies for microencapsulation at a laboratory scale is a key issue, as these technologies must be employed at an industrial scale. Like this, the main challenges are keeping the performance of the oil extraction, emulsification and selection of the correct operating conditions during the scale-up, are then crucial to the success of the process transfer. The stability and the composition of the oleo should not be affected during the microencapsulation process, yield and oil encapsulation efficiency should be high, microsphere quality and the oleo release profile should be reproducible within specified limits, microspheres should not exhibit aggregation or adherence, the process should be usable at an industrial scale, and the residual level of organic solvent should be lower than the limit value imposed by the European Pharmacopeia.

- How would stabilizing production costs on smaller quantities of processed oregano leaves impact economic viability on a large scale?

Author: Stabilizing production costs for smaller quantities of processed oregano leaves may increase unit costs due to the loss of economies of scale and operational efficiency, negatively impacting large-scale economic viability. However, this approach offers greater flexibility for quick adjustments, allowing for responses to market fluctuations, albeit with potentially higher costs. To compensate, it is essential to seek process optimizations that reduce these inefficiencies.

Reviewer 2 Report

Comments and Suggestions for Authors

The Authors have done good job and elaborated study effectively integrates environmental impact assessment and economic evaluation to compare three scenarios for producing oregano oil microparticles. Scenario B, which uses Gum Arabic as the emulsifying agent, is highlighted as the most favorable environmental performance and Scenarios A and C show better environmental outcomes in the composting of bio-waste.

Major comments:

1-    I suggested to include ANOVA table and also mean comparison table of single and multi-environment

2-    Many mistakes were found grammatically

3-    Include latest literature in introduction and discussion

Comments on the Quality of English Language

Moderately English editing required  

Author Response

Reviewer(s)' Comments to Author:

The authors would like to thank the Editor and Reviewers for allowing the opportunity to improve the quality of the manuscript. The Reviewers made significant comments and raised some queries, which during the writing process had passed unnoticed, demonstrating their dedication to the revision process. The revised version of the manuscript addresses all relevant comments and suggestions made by the Reviewers. All changes made in the manuscript are presented in the files named "Manuscript_rev", while an additional document entitled "Supporting Information_rev" was prepared with supporting data.

Below is the reply to the Reviewers' comments to support the decisions that the authors took in the revision process of this work.

 

Reviewer: 5

The Authors have done a good job and elaborated study effectively integrates environmental impact assessment and economic evaluation to compare three scenarios for producing oregano oil microparticles. Scenario B, which uses Gum Arabic as the emulsifying agent, is highlighted as the most favorable environmental performance and Scenarios A and C show better environmental outcomes in the composting of bio-waste.

Major comments:

1-    I suggested to include ANOVA table and also mean comparison table of single and multi-environment

 Author: Thank you for your valuable suggestion. While an ANOVA table and mean comparison table for single and multi-environment scenarios could provide additional insights, the primary focus of this study was on evaluating the environmental and economic feasibility of different scenarios for the production of oregano oil microparticles through microencapsulation. As such, we did not include these specific statistical analyses in our current work. However, we appreciate the potential value of these analyses and will consider incorporating them in future studies to provide a more detailed comparison and enhance the depth of our research

2-    Many mistakes were found grammatically

 Author: The text has been carefully reviewed and updated, with all grammatical errors corrected.

3-    Include latest literature in introduction and discussion

 Author: The most recent literature related to the topic of the proposed study has been incorporated into the introduction and conclusion sections. The following references have been added:

Hijo, A.A.C.T. ; Costa, J.M.G.; Silva, E.K.; Azevedo, V.M.; Yoshida, M.I.; Borges, S.V.. Understanding the Influence of Encapsulating Matrix on the Physical and Thermal Properties of Oregano Essential Oil Powder. International Journal of Horticulture & Agriculture, v. 2, p. 1-8, 2017.

Lima, N.G.; Lima, G.N.; Abreu, V.G.C.; Lopes, P.H.S; Costa, J.M.G, Effects of native oat starch on vitamin B12 microencapsulation: New perspectives on encapsulants. Powder Technology, v. 434, 2024, 119325, ISSN 0032-5910, https://doi.org/10.1016/j.powtec.2023.119325.

Meng, W; Sun, H; Mu, T; Garcia-Vaquero, M. Future trends in the field of Pickering emulsions: Stabilizers, spray-dried microencapsulation and rehydration for food applications, Trends in Food Science & Technology, v. 150, 2024, 104610, ISSN 0924-2244, https://doi.org/10.1016/j.tifs.2024.104610.

Moderately English editing required 

 Author: The text has been carefully reviewed and updated, with all grammatical errors corrected.

Reviewer 3 Report

Comments and Suggestions for Authors

After reviewing the document, different doubts, recommendations or comments arose.

It is recommended to improve the summary. It is not clear why and what the study is for.

In the emulsion preparation step. A dissolution in water at 60°C and 82°C is mentioned in the text in the different scenarios, but not in figure 1.

It is suggested to include in table 1. In the extraction stage. The yield of oregano essential oil per gram of oregano (raw material used) in the three scenarios.

It is attributed to the fact that the stages of preparation of the emulsion and essential oil extraction stage have the greatest environmental impacts specifically in freshwater eutrophication and ME = marine eutrophication.

In the conclusions, it is recommended to improve. The best conditions from the economic and environmental perspective for the microencapsulation of oregano essential oil using different ingredients or matrices are mentioned. However, there is no talk about the stability and quality of the final product or future trends in the study on this subject.

What is oregano oil specifically used for and what can its microencapsulation be used for?

Tap water is the fresh water used throughout the microencapsulation production process of oregano oil? Could it be represented as the volume of water used (mL or L) per g of encapsulated oil produced? Yes or no, why?

 

Comments on the Quality of English Language

Various typographical errors need to be corrected. Also, some words need to be corrected.

Author Response

Reviewer(s)' Comments to Author:

The authors would like to thank the Editor and Reviewers for allowing the opportunity to improve the quality of the manuscript. The Reviewers made significant comments and raised some queries, which during the writing process had passed unnoticed, demonstrating their dedication to the revision process. The revised version of the manuscript addresses all relevant comments and suggestions made by the Reviewers. All changes made in the manuscript are presented in the files named "Manuscript_rev", while an additional document entitled "Supporting Information_rev" was prepared with supporting data.

Below is the reply to the Reviewers' comments to support the decisions that the authors took in the revision process of this work.

 

Reviewer: 2

After reviewing the document, different doubts, recommendations or comments arose.

It is recommended to improve the summary. It is not clear why and what the study is for.

Author: The abstract has been updated with additional information to clarify the study's objective.

“The interest in using essential oils for biotechnological and biomedical applications has been increasing due to their unique properties, such as their roles as preservatives, antioxidants, antimicrobial agents, and therapeutic agents, with oregano oil being a notable example. However, the bioactivity and stability of oregano oil can be compromised due to its volatile nature and external factors like exposure to light, heat, or oxygen. To protect oregano oil from these adverse effects and enhance its potential, microencapsulation has been employed. Nevertheless, studies evaluating the economic feasibility of this process are still limited. In this context, this study combines an environmental impact assessment by applying the life cycle assessment (LCA) methodology and an economic evaluation for three different scenarios (A, B, and C) for the production of oregano oil microparticles by a spray dryer.”

It is suggested to include in table 1. In the extraction stage. The yield of oregano essential oil per gram of oregano (raw material used) in the three scenarios.

Author: Dried oregano leaves purchased from the Central Market of Belo Horizonte were used. The average yield was 2.8 ml of oregano oil per 100 g of dried leaves, with a controlled moisture content of 9.4%. To clearly convey this information, the following sentence was added to the Materials and Methods section:

“With this process, it was possible to obtain an average yield of 2.8 ml of oregano oil per 100 g of dried leaves.”

It is attributed to the fact that the stages of preparation of the emulsion and essential oil extraction stage have the greatest environmental impacts specifically in freshwater eutrophication and ME = marine eutrophication.

Author: We agree that the stages of emulsion preparation and essential oil extraction have significant environmental impacts, particularly in freshwater and marine eutrophication. However, it is important to highlight that the encapsulation of oregano oil can mitigate these impacts by increasing the stability and efficiency of the essential oil use, thus reducing the need for production and, consequently, the associated impacts throughout the product’s life cycle.

In the conclusions, it is recommended to improve. The best conditions from the economic and environmental perspective for the microencapsulation of oregano essential oil using different ingredients or matrices are mentioned. However, there is no talk about the stability and quality of the final product or future trends in the study on this subject.

Author: An economic and environmental perspective for the microencapsulation of oregano essential oil using different ingredients was added to the conclusion. The following sentence was included:

“Research on the stability and quality of microparticles by spray drying should be further investigated; however, recent studies show trends to improve production such as the use of different encapsulation methods, variation in operational conditions and the influence of new encapsulants.”

What is oregano oil specifically used for and what can its microencapsulation be used for?

Author: Oregano oil is a potent essential oil derived from plants with antibiotic-like properties, including antibacterial, antiviral, and antifungal effects. It can be used topically, typically mixed with a carrier oil to minimize irritation, or taken orally as an emulsified supplement, usually around 600 milligrams per day. Microencapsulation of oregano oil offers a significant advantage by protecting it from degradation due to environmental factors such as light, heat, and oxygen, thus enhancing its stability and effectiveness. This method also improves controlled release and bioavailability, making oregano oil more effective in various applications including dietary supplements and topical products.

Tap water is the fresh water used throughout the microencapsulation production process of oregano oil? Could it be represented as the volume of water used (mL or L) per g of encapsulated oil produced? Yes or no, why?

Author: Yes, tap water is the freshwater used throughout the oregano oil microencapsulation production process and could also be represented as the volume of water used (mL or L) per g of encapsulated oil produced.

Various typographical errors need to be corrected. Also, some words need to be corrected.

Author: The text has been carefully reviewed and updated, with all grammatical errors corrected.

Reviewer 4 Report

Comments and Suggestions for Authors

This study combines an environmental impact assessment by LCA and economic evaluation for the production of oregano oil microparticles by spray drying, finding out the most promising method of the scenario to satisfy the economic and environmental demands. It provides production references for the industry. I recommend this study in publication with several points being addressed.

1 In the Materials and Methods section, the background from line 96 page 2 should be arranged in the Introduction part.

2 Figure 4, why the production cost per gram of MS is higher than MS+GA+MD is not very clearly explained in the text.

3 The environmental and economic evaluation is given to what quantity of the processed oregano leaves per year?

Comments on the Quality of English Language

There are several grammar errors in the language.

Author Response

Reviewer(s)' Comments to Author:

The authors would like to thank the Editor and Reviewers for allowing the opportunity to improve the quality of the manuscript. The Reviewers made significant comments and raised some queries, which during the writing process had passed unnoticed, demonstrating their dedication to the revision process. The revised version of the manuscript addresses all relevant comments and suggestions made by the Reviewers. All changes made in the manuscript are presented in the files named "Manuscript_rev", while an additional document entitled "Supporting Information_rev" was prepared with supporting data.

Below is the reply to the Reviewers' comments to support the decisions that the authors took in the revision process of this work.

 

Reviewer: 3

This study combines an environmental impact assessment by LCA and economic evaluation for the production of oregano oil microparticles by spray drying, finding out the most promising method of the scenario to satisfy the economic and environmental demands. It provides production references for the industry. I recommend this study in publication with several points being addressed.

1 In the Materials and Methods section, the background from line 96 page 2 should be arranged in the Introduction part.

Author: The background information that was originally in the Materials and Methods section has been relocated to the Introduction.

2 Figure 4, why the production cost per gram of MS is higher than MS+GA+MD is not very clearly explained in the text.

Author: The resulting ranking of costs is mainly associated with the amount of materials required in each process option and in the amount of product generated. From the 3 encapsulation options, GA is the most expensive material, but the encapsulation yield is much larger compared to the other two options. When using MS alone, the yield is lower than the combination of the 3 materials, therefore increasing production costs per gram of final product. Additionally, when using the 3 materials simultaneously, the yield is higher and the amount of material of each is reduced which decreases the costs as well. This has been incorporated into the results to give more clarity:

“Moreover, when using MS alone, the yield is lower than the combination of the 3 materials, therefore increasing production costs per gram of the final product. Additionally, when using the 3 materials simultaneously, the yield is higher and the amount of material of each is reduced which decreases the costs as well.”

3 The environmental and economic evaluation is given to what quantity of the processed oregano leaves per year?

Author: For the economic evaluation, the quantity of oregano leaves is a variable value. As it can be noticed in Figure 4, we evaluated the range between 1 to 1,000 kg of leaves. This allowed us to analyze the impact of scalability and economy of scales in the costs of materials used. A small phrase (underlined) was incorporated into an existing sentence to reflect this:

“The quantity of materials needed per batch was calculated and extrapolated to different amounts of oregano (between 1 to 1,000 kg) leaves processed based on the scenarios presented in Figure 1”

There are several grammar errors in the language.

Author: The text has been carefully reviewed and updated, with all grammatical errors corrected.

Reviewer 5 Report

Comments and Suggestions for Authors

The present manuscript is based on a properly designed research idea and could be accepted for publication. 

 

However, a few questions require addressing before acceptance. 

 

The authors need to improve the introduction regarding the environmental and economic impacts of encapsulation of different ingredients, especially essential oils. 

 

In materials and methods, the procurement of oregano leaves is missing, but they should be added. Moreover, the age of leaves should be added to know the essential oil contents precisely. 

 

For the extraction of oil, the manufacturer of the distillation assembly and the exact extraction process should be mentioned. 

 

In the given results, statistical methods are not applied, which are required to identify the significance level. The authors should add the standard deviation and statistical symbols to express the level of significance, wherever necessary. 

 

The authors should elaborate on using landfilling or composting based on their benefits. 

 

The scientific names and abbreviations need to be revised throughout the manuscript, which should be written according to scientific guidelines. 

Author Response

Reviewer(s)' Comments to Author:

The authors would like to thank the Editor and Reviewers for allowing the opportunity to improve the quality of the manuscript. The Reviewers made significant comments and raised some queries, which during the writing process had passed unnoticed, demonstrating their dedication to the revision process. The revised version of the manuscript addresses all relevant comments and suggestions made by the Reviewers. All changes made in the manuscript are presented in the files named "Manuscript_rev", while an additional document entitled "Supporting Information_rev" was prepared with supporting data.

Below is the reply to the Reviewers' comments to support the decisions that the authors took in the revision process of this work.

 

Reviewer: 4

 

The present manuscript is based on a properly designed research idea and could be accepted for publication. However, a few questions require addressing before acceptance.

The authors need to improve the introduction regarding the environmental and economic impacts of encapsulation of different ingredients, especially essential oils.

 Author: The most recent literature related to the topic of the proposed study has been incorporated into the introduction and conclusion sections. The following references have been added:

Lima, N.G.; Lima, G.N.; Abreu, V.G.C.; Lopes, P.H.S; Costa, J.M.G, Effects of native oat starch on vitamin B12 microencapsulation: New perspectives on encapsulants. Powder Technology, v. 434, 2024, 119325, ISSN 0032-5910, https://doi.org/10.1016/j.powtec.2023.119325.

Meng, W; Sun, H; Mu, T; Garcia-Vaquero, M. Future trends in the field of Pickering emulsions: Stabilizers, spray-dried microencapsulation and rehydration for food applications, Trends in Food Science & Technology, v. 150, 2024, 104610, ISSN 0924-2244, https://doi.org/10.1016/j.tifs.2024.104610.

Mukurumbira, A.R.; Shellie, R.A.; Keast, R.; Palombo, E.A.; Jadhav, S.R. Encapsulation of Essential Oils and Their Application in Antimicrobial Active Packaging. Food Control 2022, 136, 108883, doi:10.1016/j.foodcont.2022.108883.

Sharma, S.; Mulrey, L.; Byrne, M.; Jaiswal, A.K.; Jaiswal, S. Encapsulation of Essential Oils in Nanocarriers for Active Food Packaging. Foods 2022, 11, 1–21, doi:10.3390/foods11152337.

In materials and methods, the procurement of oregano leaves is missing, but they should be added. Moreover, the age of leaves should be added to know the essential oil contents precisely.

 Author: The oregano leaves were purchased at the Central Market in Belo Horizonte, and the supplier did not provide information on the age of the leaves. Given the high turnover rate of products at the market, it is estimated that the age of the leaves is no more than one year.

For the extraction of oil, the manufacturer of the distillation assembly and the exact extraction process should be mentioned.

 Author: For the extraction of the oregano oil, a 2 L steam distillation apparatus of the Clevenger type was used, and the extractions were conducted for 240 minutes. This information was added to section 2.1 Extraction of Oregano Essential Oil (Step 1) to clarify for the reader.

“in which the oregano leaves, together with water, were extracted in a traditional method of steam distillation using 2 L steam distillation Clevenger type apparatus, using the extraction time of 240 minutes given the best oil yield (content) per 100 g of dry oregano leaves, finally obtaining the concentrated oregano essential oil and the residue of the leaves of the process.”

In the given results, statistical methods are not applied, which are required to identify the significance level. The authors should add the standard deviation and statistical symbols to express the level of significance, wherever necessary.

 Author: Thank you for your valuable feedback. The primary focus of this study was to evaluate the environmental and economic feasibility of different scenarios for the production of oregano oil microparticles using microencapsulation, with an emphasis on comparing the performance of various encapsulation materials and end-of-life scenarios. Given this focus, we did not include detailed statistical analyses or calculations of standard deviations in our current work. However, we recognize the importance of statistical evaluation and plan to incorporate these analyses in future research to enhance the robustness of our findings. Your suggestion is appreciated and will be addressed in our subsequent studies.

The authors should elaborate on using landfilling or composting based on their benefits.

 Author: The discussion on the benefits of using landfilling versus composting is covered at the beginning of Section 3. Generally, composting is considered preferable to landfilling, and this is discussed in the following text.

“The comparison of the EoL alternatives of biowaste shows that, for all scenarios, composting presents lower environmental impacts for ME and GW, reaching a reduction of around 17% for ME (due to lower emissions of nitrate and ammonium to water) and around 7% for GW (due to lower emissions of methane and nitrous oxide to air) compared to landfilling. However, composting increases by around 4% the TA (due to higher ammonia emissions) in comparison to landfilling. For the remaining impact categories, the impacts from biowaste landfilling and composting are similar.”

The scientific names and abbreviations need to be revised throughout the manuscript, which should be written according to scientific guidelines.

Author: The text has been carefully reviewed and updated.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Authors responded to my comments and improved the manuscript as accordingly 

Author Response

Reviewer(s)' Comments to Author:

The authors thank the Reviewers and Editor for their comments, which have been fully addressed in the second round of revisions. The updates are detailed in the revised files. Below is the reply to the Reviewers' comments to support the decisions that the authors took in the revision process of this work.

Reviewer: 1

Comments and Suggestions for Authors

Authors responded to my comments and improved the manuscript as accordingly 

Author: Thank you for your feedback and for helping improve the manuscript.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

After reviewing the document, the following questions and comments arise that the authors should address:

1.-In materials and methods. What is expressed in the text does not match what is indicated in figure 1 specifically for scenario A, it is not clear.

The text mentions: Then, these ingredients 156 were dissolved in distilled water at 60°C using the Ultra Turrax homogenizer at a speed 157 of 20,000 rpm for 30 min. Subsequently, they were refrigerated to a temperature below 158 10°C, where the essential oil of oregano was added, rotating at 20,000 rpm for 5 min, until 159 a completely homogeneous emulsion was obtained. (Not reflected in the figure)

2.-It is not clear in the manuscript. How do microencapsulation, preparation of the emulsion and oil extraction influence the phenomenon of freshwater eutrophication and marine eutrophication?

3.-It is mentioned that the oil extraction stage has the greatest impact on freshwater eutrophication and marine eutrophication. To what is this attributable? More information.

4.-It is not clear. If oil extraction has the greatest impact on freshwater eutrophication and marine eutrophication, it is between these two factors. Where would there be greater or lesser impact from oil extraction, microencapsulation and emulsion preparation? And why? More information.

 

Author Response

Reviewer(s)' Comments to Author:

The authors thank the Reviewers and Editor for their comments, which have been fully addressed in the second round of revisions. The updates are detailed in the revised files. Below is the reply to the Reviewers' comments to support the decisions that the authors took in the revision process of this work.

Reviewer: 2

Comments and Suggestions for Authors

After reviewing the document, the following questions and comments arise that the authors should address:

1.-In materials and methods. What is expressed in the text does not match what is indicated in figure 1 specifically for scenario A, it is not clear.

Author: Thank you for your valuable suggestion. The sentence “The modified starch was added at 82°C, maintaining homogeneity until complete dissolution of the wall materials”, was detailed in Materials and Methods in scenario A.

The text mentions: Then, these ingredients 156 were dissolved in distilled water at 60°C using the Ultra Turrax homogenizer at a speed 157 of 20,000 rpm for 30 min. Subsequently, they were refrigerated to a temperature below 158 10°C, where the essential oil of oregano was added, rotating at 20,000 rpm for 5 min, until 159 a completely homogeneous emulsion was obtained. (Not reflected in the figure)

Author: The figure has been updated with the correct conditions as described in the text.

2.-It is not clear in the manuscript. How do microencapsulation, preparation of the emulsion and oil extraction influence the phenomenon of freshwater eutrophication and marine eutrophication?

Author: The impact of freshwater eutrophication (FE) and marine eutrophication (ME) was assessed across different study scenarios using the ReCiPe 2016 midpoint method (refer to reference 44 of the article). This model quantifies the contributions of phosphorus (P) and nitrogen (N), which are key factors in FE and ME, respectively, in terms of kilograms. In Table S2, the reviewer can find the contribution of these two parameters for the production of 1 g of oregano essential oil microparticles considering the three scenarios analysed, and end-of-life alternatives of the biowaste (landfilling or composting).

3.-It is mentioned that the oil extraction stage has the greatest impact on freshwater eutrophication and marine eutrophication. To what is this attributable? More information.

Author:  The oil extraction stage has a substantial impact on freshwater and marine eutrophication, mainly due to nutrient runoff and pollution resulting from the cultivation of oilseed crops and the extraction processes. Additionally, pollution from the oil extraction methods, including the discharge of chemical residues and organic matter, further exacerbates nutrient imbalances in aquatic environments. Conventional vegetable oil production methods have a high environmental footprint, significantly contributing to these issues. To make this clear to the reader, the following text were added to the manuscript:

“For ME, the main contribution comes from the oregano cultivation, with an average of 80 %, mainly due to the use of organic fertilizers during oregano growth and the and pollution from oilseed crop cultivation and extraction processes.”

 “As seen by previous authors, the FE and ME are intrinsically connected to the amount of kg of P and N generated; and found to be present in vegetable oil extraction studies. [47,48]”

4.-It is not clear. If oil extraction has the greatest impact on freshwater eutrophication and marine eutrophication, it is between these two factors. Where would there be greater or lesser impact from oil extraction, microencapsulation and emulsion preparation? And why? More information.

Author:  As shown in Figure 2, essential oil extraction is the primary contributor to marine eutrophication (ME) due to its higher N emissions per gram of product. For freshwater eutrophication (FE), both essential oil extraction and microencapsulation have significant impacts, as they generate a higher amount of P per gram of product. For ME, the main contribution comes from the oregano cultivation (part of essential oil extraction), with an average of 80 %, mainly due to the use of organic fertilizers during oregano growth. For the FE, the contribution of oregano oil cultivation is also significant, but also the final step on the microencapsulation on the final packing and raw materials.