Tea Infusions as a Source of Phenolic Compounds in the Human Diet
Round 1
Reviewer 1 Report
The manuscript of Klepacka is linear, rigorous and clearly presented. The paper is well written and structured. Furthermore, the methods used and the results collected were correctly interpreted from a statistical point. The novelty of this study is not clear,
The document contains the appropriate updated references.
In my opinion, the manuscript can be published, without modification, in present form.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript addresses an interesting research topic; the results were well presented and discussed. However, I felt I was reading a review manuscript because the discussion was very extensive and descriptive.
It would significantly improve the quality of the manuscript a polyphenolic characterization by a chromatographic technique, like HPLC-DAD or even LC-MS. It would help relating the type of polyphenols with extraction times and will help explaining the differences observed between tea types.
The large description of other references in literature demonstrates the lack of novelty in this work. Is not clear in any part of the manuscript what this work came to add new information. There are a lot of variables responsible for polyphenols richness in teas, beside the extraction time, making not possible to make general conclusions about the ideal conditions for tea intake.
The title mention tea phenolics in the human diet. Yet any analysis related with human diet was performed. This relation is based on literature assumptions.
If manuscript had line numbers, it would be easier to identify the corrections.
Materials and methods
Section 2.2: space between numbers and units “14 %”; “0.04 mL”, 1 h and not 1 hour.
Section 2.3: 5 %; 6 °C; 5000 rpm should come in G’ force; 10 %.
Revise the entire document for units SI.
Results
This section should be called results and discussion.
Use 20 or 30 min instead 20/30 minutes.
Table 1 Extraction time had no units.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 3 Report
This paper by Klepacka presents an interesting study on the phenolic (and some mineral) content of different teas brewed for different times.
The introduction is of appropriate length and depth with good citation to relevant literature. The methods and materials are of appropriate depth and very clear and the results are well analysed, described and discussed. The conclusions are well-supported by the results.
Overall, this is an interesting (although not entirely novel, with other similar research having been published) and well-described study and I am in agreement of it being published, provided some changes are made (see details below):
- I would like the authors to add a Figure with the (general) structures of some of the compounds of interest mentioned in the introduction and/or results and discussion.
- The author does not state how the tea samples were stored, once made and prior to analysis. Were samples analysed immediately or were they frozen, etc?
- Line 226: instead of "statistically the same" the author should change their wording to "not significantly different".
- If the author could graphically represent the results in Table 1 (in addition to the table), I think this would greatly enhance the reading experience of the readers.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
I suggest this manuscript can be accepted in the present form.
