Properties of Green Tea Waste as Cosmetics Ingredients and Rheology Enhancers

Round 1

Reviewer 1 Report

The article entitled “Properties of Green Tea Waste as Cosmetics Ingredients and Rheology Enhancer” is very interesting from a practical and fundamental point of view due to the necessity to expand the knowledge about the application of green tea waste. The paper is well-written: However, I think the rheological results are very limited.  In general, a deeper insight into rheological measurements is necessary.

Line 177. I wonder if the geometry used is serrated or smooth since a serrated one is necessary for nanoparticles dispersions.

Line 180. Please use superscripts.

Line 227-235. If the authors prepare nanoemulsions and nanoparticles, the zeta potential is also important for the aggregation of the particles.

Figure 4. Firstly, the authors should mark the differences between the behaviours of DS 0 and DS0.3/ DS 0.4 (Newtonian, not Newtonian character). In addition, they could fit the flow curves to some rheological models such as power law, Cross model…

Figure 5. The analysis of rheology is poor. If the authors have measured the strain sweep, they should measure the frequency sweeps to characterize the samples' microstructure.

The following article can be helpful:

Santos, J., Trujillo-Cayado, L. A., Barquero, M., & Calero, N. (2022). Influence of Type and Concentration of Biopolymer on β-Carotene Encapsulation Efficiency in Nanoemulsions Based on Linseed Oil. Polymers, 14(21), 4640.

Author Response

Open Review

(x) I would not like to sign my review report

( ) I would like to sign my review report

English language and style

( ) English very difficult to understand/incomprehensible

( ) Extensive editing of English language and style required

( ) Moderate English changes required

( ) English language and style are fine/minor spell check required

(x) I don't feel qualified to judge about the English language and style

Yes       Can be improved Must be improved          Not applicable

Does the introduction provide sufficient background and include all relevant references?

(x)        ( )        ( )        ( )

Are all the cited references relevant to the research?

( )        (x)        ( )        ( )

Is the research design appropriate?

( )        ( )        (x)        ( )

Are the methods adequately described?

( )        (x)        ( )        ( )

Are the results clearly presented?

( )        (x)        ( )        ( )

Are the conclusions supported by the results?

( )        (x)        ( )        ( )

Comments and Suggestions for Authors

The article entitled “Properties of Green Tea Waste as Cosmetics Ingredients and Rheology Enhancer” is very interesting from a practical and fundamental point of view due to the necessity to expand the knowledge about the application of green tea waste. The paper is well-written: However, I think the rheological results are very limited.  In general, a deeper insight into rheological measurements is necessary.

Line 177. I wonder if the geometry used is serrated or smooth since a serrated one is necessary for nanoparticles dispersions.

• Parallel-plate geometries with the stationary bottom plate sandblasted surfaces and smooth surface upper plate are used. This geometry usually uses for pharmaceutical, cosmetics, medical, and food industries samples.
• For very slippery samples and for materials exhibiting interfacial slippage or gliding effects along external surfaces, and for sliding rigid solids, it is necessary to use a measuring geometry with a serrated surface, like waxes, elastomers, rubbers, or hard cheese. However, GTW nanoparticles hydrogel is not a very slippery sample, smooth geometry is enough to use.

Here are other articles that used smooth geometry:

Datta, A., Tanmay, V. S., Tan, G. X., Reynolds, G. W., Jamadagni, S. N., & Larson, R. G. (2020). Characterizing the rheology, slip, and velocity profiles of lamellar gel networks. Journal of Rheology, 64(4), 851-862.

Ozkan, S., Gillece, T. W., Senak, L., & Moore, D. J. (2012). Characterization of yield stress and slip behaviour of skin/hair care gels using steady flow and LAOS measurements and their correlation with sensorial attributes. International journal of cosmetic science, 34(2), 193-201.

Shafi, W. K., & Charoo, M. S. (2019). Experimental study on rheological properties of vegetable oils mixed with titanium dioxide nanoparticles. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 41(10), 1-13.

Lade, R., Wasewar, K., Sangtyani, R., Kumar, A., Shende, D., & Peshwe, D. (2019). Effect of aluminum nanoparticles on rheological behavior of HTPB-based composite rocket propellant. Journal of Energetic Materials, 37(2), 125-140.

Line 180. Please use superscripts.

• Solved

Line 227-235. If the authors prepare nanoemulsions and nanoparticles, the zeta potential is also important for the aggregation of the particles.

• I only make GTW DS nanoparticles, this sample only contains a negative charge (anion) from carboxyl groups and glucuronic acid, so it does not have aggregation. I did not make nanoemulsion, I cited from other papers. I already corrected the manuscript (lines 251-256).

Figure 4. Firstly, the authors should mark the differences between the behaviours of DS 0 and DS0.3/ DS 0.4 (Newtonian, not Newtonian character). In addition, they could fit the flow curves to some rheological models such as power law, Cross model…

•  

This figure is Viscosity functions show dynamic viscosity vs. shear rate. Different types of flow behavior: Newtonian = ideally viscous (1) | Shear-thinning (2) | Shear-thickening (3)

• The DS 0 was shear thinning but the viscosity is really low, while DS 0.3 and DS 0.4 have higher viscosity that has the type of non-Newtonian behavior were shear thinning, where the fluid viscosity decreases with increasing shear, with the value closer to zero indicates a more shear-thinning material.

Based on this figure the GTW nanoparticles were shear thinning (looks like line number 2). I have changed in the script (lines 293, 305)

Figure 5. The analysis of rheology is poor. If the authors have measured the strain sweep, they should measure the frequency sweeps to characterize the samples' microstructure.

The following article can be helpful:

Santos, J., Trujillo-Cayado, L. A., Barquero, M., & Calero, N. (2022). Influence of Type and Concentration of Biopolymer on β-Carotene Encapsulation Efficiency in Nanoemulsions Based on Linseed Oil. Polymers, 14(21), 4640.

• Thank you for the reference. I think the initial identification of existing data was sufficient, but the frequency sweep is important. Unfortunately, I need more time to measure the sweep frequency. I prefer will to be added later as supplementary data.

 

 

Submission Date

11 November 2022

Date of this review

28 Nov 2022 10:20:05

© 1996-2022 MDPI (Basel, Switzerland) unless otherwise stated

Author Response File: Author Response.docx

Reviewer 2 Report

Dear Author,

The work is very interesting, but I want to suggest something for the value addition of the manuscript.

1. Keywords should be in alphabetic order.
2. In the Introduction part, page no. 02, line no. 67, first line: gr refers to a gram or something else?
3. Pennells et al, 2020, repetition of the same citation, kindly remove the previous one (i.e., line no. 89, page no. 02).
4. Page no. 3-4, in materials and methods, for 2.3, kindly provide proper citations for each analysis method.
5. Page no. 7, section 3.3, line no. 249, for this citation (Plappert et al.,), year is missing.
6. Page no. 7, line no. 256, section numbering is wrong, it should be 3.4.
7. Fewer citations are recent, all other citations are old in the discussion part. It will be better to cite recent references at least within the last 5 years.
8. In the conclusion part, what is the range of these compositions which is suitable for skincare in general?
9. Format the references as per journal guidelines by referring latest papers. The scientific name should be in italics with proper format.

 

In the revised manuscript, the corrected part should be marked with some color or highlighted with a different color so that corrections/changes can be identified.

Comments for author File: Comments.pdf

Author Response

Open Review

( ) I would not like to sign my review report

(x) I would like to sign my review report

English language and style

( ) English very difficult to understand/incomprehensible

( ) Extensive editing of English language and style required

( ) Moderate English changes required

(x) English language and style are fine/minor spell check required

( ) I don't feel qualified to judge about the English language and style

Yes       Can be improved Must be improved          Not applicable

Does the introduction provide sufficient background and include all relevant references?

(x)        ( )        ( )        ( )

Are all the cited references relevant to the research?

(x)        ( )        ( )        ( )

Is the research design appropriate?

(x)        ( )        ( )        ( )

Are the methods adequately described?

( )        (x)        ( )        ( )

Are the results clearly presented?

(x)        ( )        ( )        ( )

Are the conclusions supported by the results?

(x)        ( )        ( )        ( )

Comments and Suggestions for Authors

Dear Author,

 

The work is very interesting, but I want to suggest something for the value addition of the manuscript.

Karyanya sangat menarik, tetapi saya ingin menyarankan sesuatu untuk nilai tambah naskah.

Keywords should be in alphabetic order.

• Solved

In the Introduction part, page no. 02, line no. 67, first line: gr refers to a gram or something else?

• Im sorry for the typo, it should be gram and I already solved it.

Pennells et al, 2020, repetition of the same citation, kindly remove the previous one (i.e., line no. 89, page no. 02).

• Solved

Page no. 3-4, in materials and methods, for 2.3, kindly provide proper citations for each analysis method.

• Solved

Page no. 7, section 3.3, line no. 249, for this citation (Plappert et al.,), year is missing.

• Solved

Page no. 7, line no. 256, section numbering is wrong, it should be 3.4.

• Solved

Fewer citations are recent, all other citations are old in the discussion part. It will be better to cite recent references at least within the last 5 years.

• Thank you, I find it as much as I can for this week but some of them are still older than 5 years.

In the conclusion part, what is the range of these compositions which is suitable for skincare in general?

• The composition of skincare cosmetics is different for every type so I cannot generate it because it depends on the type of skincare. Every skincare has a different component and composition. So, I don’t know how much our material should be in different skincare types.

Format the references as per journal guidelines by referring latest papers. The scientific name should be in italics with proper format.

• Solved

 

In the revised manuscript, the corrected part should be marked with some color or highlighted with a different color so that corrections/changes can be identified.

• Yes, for correcting I made it with red color.

 

peer-review-24708305.v1.pdf

Submission Date

11 November 2022

Date of this review

01 Dec 2022 23:58:20

© 1996-2022 MDPI (Basel, Switzerland) unless otherwise stated

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

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