Glycaemic Index of Bakery Products and Possibilities of Its Optimization

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The review as a whole is well written. But there are problems. Reviews are often illustrated so that readers can easily understand the current research through pictures. However, this article lacks the support of pictures. Authors should consider providing more intuitive pictures.

Author Response

RESUBMISSION OF THE MANUSCRIPT ID applsci-3003103, Review: Glycaemic index of bakery products and possibilities of its optimization

COVER LETTER WITH RESPONSES TO REVIEWERS´ COMMENTS

Dear Editorial Office,

we have revised and modified the text according to the reviewers’ comments and suggestions. We have responded to reviewers’ comments and remarks as follow:

 

Reviewer 1:

The review as a whole is well written. But there are problems. Reviews are often illustrated so that readers can easily understand the current research through pictures. However, this article lacks the support of pictures. Authors should consider providing more intuitive pictures.

Authors´ answers and corrections: We would like to add pictures, but we are not sure if we understand what we should mean by “more intuitive pictures”. The extended table with the starch content and glycaemic index value of selected grains and seeds, and bakery products has been added.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Introduction:

Authors are recommended to strengthen the introduction section. Although there is an abundance of information about cereals and their health implications, some specific data can be added. For example, it is recommended to add the specific definition of glycemic index; add some glycemic index data of the most common cereals; the starch content in the main cereals; the classification of starch based on its digestibility.

It is also recommended to cite relevant articles that precede this manuscript. For example, are there any reviews on the glycemic index of cereals and baking products? This information should be cited here. The novelty of the present manuscript should be highlighted.

Lines 85-94: This section describes the epidemiological situation of diabetes in the Czech Republic. Subsequently, lines 95-101, the main cereals in Europe are described. Authors are recommended to distribute this information in independent paragraphs to improve the scientific style of the manuscript.

It is recommended to review bibliography citation no. 17, which supports table 1 (chemical composition of cereals). This information is not found in the bibliographic reference.

What does the number 1 in parentheses shown after the title Glycaemic index in Table 1 mean?

Section 3 "Overview of technological routes to modify the glycemic index of bakery products 351 and their evaluation", although well described in the manuscript, seems very general in relation to the information available in the literature. Authors are recommended to review and include background information in a particular manner. For example, inserting a table that summarizes important background information and describes findings in relation to fiber-added baking products (among other approaches) would be interesting to improve the relevance of the manuscript.

 

 

Author Response

RESUBMISSION OF THE MANUSCRIPT ID applsci-3003103

Review: Glycaemic index of bakery products and possibilities of its optimization

 

COVER LETTER WITH RESPONSES TO REVIEWERS´ COMMENTS

Dear Editorial Office,

we have revised and modified the text according to the reviewers’ comments and suggestions. We have responded to reviewers’ comments and remarks as follow:

 

Reviewer 2:

Introduction: Authors are recommended to strengthen the introduction section. Although there is an abundance of information about cereals and their health implications, some specific data can be added. For example, it is recommended to add the specific definition of glycemic index; add some glycemic index data of the most common cereals; the starch content in the main cereals; the classification of starch based on its digestibility.

 

Authors´ answers and corrections: The definition and description of the glycaemic index has been added. The table with the starch content and glycaemic index value of selected grains and seeds, and bakery products has been added to chapter 2. Cereals as an important source of starch - importance in human nutrition with respect to glycaemic index.

 

The glycaemic index is a dimensionless quantity that indicates the rate of increase in postprandial glycaemia from a particular food. Exactly, the GI is defined as the area under the glycaemia curve within two hours after ingestion of a given food, expressed as the proportion of the area under the curve after ingestion of the same amount of carbohydrate in the form of pure glucose. The glycaemic index is always a guideline number, it depends very much on the specific composition and processing of the food. Each organism reacts slightly differently and is sensitive to fluctuations in sugar levels. The glycaemic index related to pure glucose is sometimes confused with the Brot-index used in Germany, which refers to white wheat bread, which has a glycaemic index of 70. As a result, there is often confusion about the numbers in the various tables reported in the literature.

 

 

 

 

 

 

 

 

Table 2. Starch content and glycaemic index of cereals, legumes, pseudocereals and selected cereal products based on data from National Institute of Health, Czech Republic) (https://szu.cz/wp-content/uploads/2023/12/Glykemicky-index-2003.pdf) [18] [19-21].

Crops-whole grains	Starch content (% in d.m.)	Glycaemic index
Wheat	65-75	50-60
Rye	65-75	50-60
Barley	65-75	50-60
Oat	55-65	40-50
Rice	70-80	55-60
Maize	60-70	50-60
Sorghum	65-75	55-65
Millet	70-80	55-65
Legumes	45-55	30-45
Buckwheat	45-55	35-45
Amaranth	55-60	30-40
Bread and bakery products
White wheat bread	70-75	70
Wheat-rye bread (Central Europe type)	65-70	65-70
Dark rye bread	55-65	45-55
Whole grain bread	55-65	45-55
Bread type pumpernickel	55-65	45-55
Buckwheat bread	50-60	40-50
Wheat common bakery products	70-75	70
Croissants	50-60*	60-70*
Donuts	45-60*	70-75*
Muffins and other sweet pastry	45-60*	60-75*

* Starch content and glycaemic index decrease with higher fat content

 

 

It is also recommended to cite relevant articles that precede this manuscript. For example, are there any reviews on the glycemic index of cereals and baking products? This information should be cited here. The novelty of the present manuscript should be highlighted.

 

Authors´ answers and corrections: The table with the required data has been added to revised manuscript.

Citations were added.

This manuscript is a review summarizing information from the literature. We are not sure how we should emphasize its relevance (novelty).

 

 

Lines 85-94: This section describes the epidemiological situation of diabetes in the Czech Republic. Subsequently, lines 95-101, the main cereals in Europe are described. Authors are recommended to distribute this information in independent paragraphs to improve the scientific style of the manuscript.

 

Authors´ answers and corrections: Information was separated.

According to statistical predictions, there will be almost 1.3 million people with diabetes in the Czech Republic in 2030 [15]. It is therefore a real epidemic with widespread personal, social and economic consequences.

The situation is very similar in other Central European countries. The main (bread) cereals in Central Europe are wheat (Triticum aestivum L.), which accounts for 80-90% of bread and pastry production, and rye (Secale cereale L.), which accounts for 10-15% (historically, its share of bread and pastry production in Central Europe was much higher).

Other cereals (barley, oats, maize) and the pseudocereal buckwheat or other cereals contribute marginally to the production of bakery flours. The importance of buckwheat has increased slightly in recent decades in the context of gluten-free products [16].

 

 

It is recommended to review bibliography citation no. 17, which supports table 1 (chemical composition of cereals). This information is not found in the bibliographic reference.

What does the number 1 in parentheses shown after the title Glycaemic index in Table 1 mean?

Authors´ answers and corrections: Citation 17: Velíšek, J. The Chemistry of Food. John Wiley & Sons, New York City, USA, 2013; pp. 51.

The number 1 in brackets [1] indicated a dimensionless number of glycaemic index. It has been corrected.

 

 

Section 3 "Overview of technological routes to modify the glycemic index of bakery products 351 and their evaluation", although well described in the manuscript, seems very general in relation to the information available in the literature. Authors are recommended to review and include background information in a particular manner. For example, inserting a table that summarizes important background information and describes findings in relation to fiber-added baking products (among other approaches) would be interesting to improve the relevance of the manuscript.

 

Authors´ answers and corrections: The extended table with the required data has been added to revised manuscript.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The review performed is of low quality, the conclusions drawn inadequate, and the manuscript was not prepared with sufficient care. If the manuscript gets great improvement after revision, it can be considered accepted.

1.        Abstract, main findings and conclusions are necessary for the abstract.

2.        Introduction, the introduction appears to be very lengthy and rather broad, without enough reference to the aims or objectives of the study. Please rewrite, and make it more concise about research.

3.        The introduction did not provide a good overview of the topic. The novelty of the work (and how it is filling the current gap) is missing. Has any similar study been published before? What difference does your work make?

4.        More concise titles are needed for each section.

5.        The structure of this review should be reorganized to improve readability.

 

6.        Recent studies related to modifying the glycemic index of bakery products should be summarized in a table including the main findings. Furthermore, what is the advantages and disadvantages of each strategy for modifying the glycemic index of bakery products should be also summarized in a table.

Author Response

RESUBMISSION OF THE MANUSCRIPT ID applsci-3003103

Review: Glycaemic index of bakery products and possibilities of its optimization

 

COVER LETTER WITH RESPONSES TO REVIEWERS´ COMMENTS

Dear Editorial Office,

we have revised and modified the text according to the reviewers’ comments and suggestions. We have responded to reviewers’ comments and remarks as follow:

 

Reviewer 3:

The review performed is of low quality, the conclusions drawn inadequate, and the manuscript was not prepared with sufficient care. If the manuscript gets great improvement after revision, it can be considered accepted.

 

1. Abstract, main findings and conclusions are necessary for the abstract.
2. Introduction, the introduction appears to be very lengthy and rather broad, without enough reference to the aims or objectives of the study. Please rewrite, and make it more concise about research.
3. The introduction did not provide a good overview of the topic. The novelty of the work (and how it is filling the current gap) is missing. Has any similar study been published before? What difference does your work make?
4. More concise titles are needed for each section.
5. The structure of this review should be reorganized to improve readability.
6. Recent studies related to modifying the glycemic index of bakery products should be summarized in a table including the main findings. Furthermore, what is the advantages and disadvantages of each strategy for modifying the glycemic index of bakery products should be also summarized in a table.

 

Authors´ answers and corrections:

Ad 1. This is a review. It is not clear which findings and conclusions should be added to the abstract.

 

Ad 2. and ad 3. To our knowledge, a study summarising the technological aspects of glycaemic index influence has not been published in a similar form. This is where we see its novelty.

 

Ad 6. The table with the extended data with the starch content and glycaemic index value of selected grains and seeds, and bakery products has been added to revised manuscript.

Citations were added.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors addressed the observations previously indicated. Approval of the manuscript is advised.

Author Response

RESUBMISSION (II) OF THE MANUSCRIPT ID applsci-3003103

Review: Glycaemic index of bakery products and possibilities of its optimization

 

COVER LETTER WITH RESPONSES TO REVIEWERS´ COMMENTS and at the request of the editors

 

Dear Editorial Office,

we have modified the text according to the reviewers’ comments.

The importance of the review in relation to its content was emphasised. Parts of the abstract and introduction have been modified.

Abstract: Common bakery and many other cereal products are characterised by high glycaemic index values. Given the increasing number of people suffering from type 2 diabetes at a very young age, technological approaches to reduce the glycaemic index of cereal products are extremely important. In addition to increasing the dietary fibre content, either by using wholemeal flours or flours with added fibre from other sources, practices leading to an increase in resistant starch content are also of great interest. This review summarises the most important technological processes used to reduce the glycaemic index of bread and other bakery products. The summarization shows that the potential of various technological processes or their physical and physicochemical modifications to reduce the glycaemic index of common bakery products exists. At the same time, however, it has been shown that these processes have not been sufficiently explored, let alone applied in production practice.

 

Contribution to the introduction section:

The contribution of our work and its novelty in terms of summarizing and profiling the available literature data lies in the focus on the relationship between technological processes and their influence on the glycaemic index of bread and bakery products. We focused in particular on the relationship between the transitions of starch types (modifications) in terms of its digestibility, i.e. RDS (rapid digestible starch), SDS (slow digestible starch) and RS (resistant starch) and the physical and physicochemical conditions of the production processes. These include hydrothermal treatment, fermentation and heat treatment. A similar summary from this point of view has not yet been published, according to all available information.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

There was no significant improvement in the revised version. 

Author Response

RESUBMISSION (II) OF THE MANUSCRIPT ID applsci-3003103

Review: Glycaemic index of bakery products and possibilities of its optimization

 

COVER LETTER WITH RESPONSES TO REVIEWERS´ COMMENTS and at the request of the editors

 

Dear Editorial Office,

we have modified the text according to the reviewers’ comments.

The importance of the review in relation to its content was emphasised. Parts of the abstract and introduction have been modified.

Abstract: Common bakery and many other cereal products are characterised by high glycaemic index values. Given the increasing number of people suffering from type 2 diabetes at a very young age, technological approaches to reduce the glycaemic index of cereal products are extremely important. In addition to increasing the dietary fibre content, either by using wholemeal flours or flours with added fibre from other sources, practices leading to an increase in resistant starch content are also of great interest. This review summarises the most important technological processes used to reduce the glycaemic index of bread and other bakery products. The summarization shows that the potential of various technological processes or their physical and physicochemical modifications to reduce the glycaemic index of common bakery products exists. At the same time, however, it has been shown that these processes have not been sufficiently explored, let alone applied in production practice.

 

Contribution to the introduction section:

The contribution of our work and its novelty in terms of summarizing and profiling the available literature data lies in the focus on the relationship between technological processes and their influence on the glycaemic index of bread and bakery products. We focused in particular on the relationship between the transitions of starch types (modifications) in terms of its digestibility, i.e. RDS (rapid digestible starch), SDS (slow digestible starch) and RS (resistant starch) and the physical and physicochemical conditions of the production processes. These include hydrothermal treatment, fermentation and heat treatment. A similar summary from this point of view has not yet been published, according to all available information.

Author Response File: Author Response.docx