Decontamination of Powdery Foods Using an Intense Pulsed Light (IPL) Device for Practical Application

Round 1

Reviewer 1 Report

Title: Decontamination of powdery foods using intense pulsed light (IPL) device for practical application

The authors describe in this manuscript the use of an intense pulsed light (IPL) to decontaminate powdery and dried foods. They used a lamp with DC voltage of 1800-4500V, a pulse width of 0.5-1.0 ms and a frequency of 2Hz. The treatment time was set to 1 to 5 min and they were able to significantly reduce the microbial CFU/ml without a significant change in colour, water activity and moisture content.

From my point of view, the title is explicitly well written even though the whole idea is not novel the abstract is well organised, contained all necessary information for a clear understanding of the article. However, there are still some few things that needed to be addressed. The draft manuscript is not properly formatted and makes it difficult to read and comment.

The introduction lacks references.

Line 45-6: this sentence is not understandable, please re-write it.

Line 59-61: this sentence is not complete, otherwise, “However” should be removed.

Line 64-66: the sentence is not well organised with “ Therefore”, it should be re-written.

Material and method

How do you determine the contamination level? This needed to be thoroughly described. Was it artificial contamination? Were the foods plated on solid media and microbial colonies being counted?

What do you mean by “uniform quality”? was keeping the food for 3 weeks part of the procedure?

What are the targeted microorganisms, were they bacteria? Fungi?

Line 121: “range from 1800 to 5000 V” but the abstract says 1800V to 4500V, it should be uniformised throughout the text

Figure 1&2: Contents are not properly displayed.

Microorganism count: That is the reason why a qualitative and quantitative detection of microorganism should be performed before and after treatment. Because the authors do not know which microorganisms to look for, they just used agar plates to grow them. I do not think this is sufficient. At least, the authors should thoroughly scan for bacteria and fungi using appropriate culture media and incubation conditions.  Etc...

Line 251-253: the use of “while” is not appropriate in these sentences or, they needed to be re-written.

Now the authors start interpreting their results based on microorganism without determining which one were present in their samples. I think the methodology is not sufficient.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Pathogen destruction and microbial decontamination( in general ) of food is one of the key challenge for the food industry. Non-thermal methods have been developed in the last decades because of several advantages over the conventionally used thermal microbial decontamination processes. From technological purposes the solid foods and raw materials, especially the powdered food has many difficulties. Development of non-thermal and easily controllable methods for powders food has high importance in the field of food engineering.

Therefore, manuscript applsci-1076049 entitled as ’ Decontamination of powdery foods using intense pulsed light (IPL) device for practical application’ provide interesting information for the research and industry practice, as well.

Manuscript is generally well written with a logic structure. The background of the research (need for efficient non-thermal methods, principles of IPL) and research motivations are defined clearly in the Introduction section. Materials and methods are described clearly. Manuscript contains interesting results. Results are discussed in details with relevant references.

 

Comments, suggestions:

I ask for the authors to reposition the figures in the manuscript.

Table 1 presents the results of colour measurement, but table does not provide the errors/deviations.

Manuscript has not a real Conclusion section I suggest the authors to give a brief conclusion to highlight the main ‘essence’ of study.

I suggest the authors to give a brief discussion of energy demand and energetic efficiency of IPL (compare to other non-thermal microbial decontamination methods)

I suggest the authors to discuss the change of sensory parameters (taste, smell etc) exposed to IPL (not just the colour difference), as well. (based on previous studies, if authors have not own measured data).

Author Response

Please see the attachment

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

1. The introduction section has been re-written, references have been added, however, there still needs some English improvement.
2. The added line 48-51: not grammatically clear.
3. Fine
4. Fine
5. Agree
6. The concern was not answered. Did I want to know if keeping the samples in the fridge for a maximum of 3 weeks is part of the procedure? Why do you have to keep them refrigerated for 3 weeks?
7. What is the meaning of “indigenous bacteria” in this context? Again, my concern is not addressed. the methodology should clearly state if your procedure is targeting bacteria or fungi? How do you count colonies if you do not know what they are? How do you grow them?
8. Fine
9. Not addressed, the manuscript is not properly formatted.
10. No doubt you have done it, but state it in the text with supported results, I cannot see it anywhere.
11. Fine
12. Not clearly addressed.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Manuscript applsci-1076049 has an interesting topic. Intense pulsed light (IPL) is a promising technology for powdery food decontamination. Authors have revised the manuscript thoroughly, according to reviewers' comments and suggestions. After the revision the manuscript has been more clear and complete. I accept all answers and modifications and recommend the manuscript applsci-1076049 for publishing.

Author Response

Thanks for your positive response. We attach the revised manuscript.

Author Response File: Author Response.docx