Identification of Stingless Bee Honey Adulteration Using Visible-Near Infrared Spectroscopy Combined with Aquaphotomics
, Jelena Muncan 2, Musfirah Zulkurnain 3 and Abdul Rahman Abdul Najib 1
Round 1
Reviewer 1 Report
please kindly revise followed my comment in attachment
Comments for author File: 
Comments.pdf
Author Response
The responses to the reviewers' comments are in the attached pdf file.
Author Response File: Author Response.pdf
Reviewer 2 Report
The authors provide results on SBH adulteration by VIS-NIR spectroscopy. There are some general notices on the manuscript:
1) relatively low number of samples
2) lack of samples being a mix of adulterants, their location in PCA scores would be interesting
3) separated PLS models built for each adulterant would give information on minimal contamination that can be detected in honey samples, but their validation will be problematic due to 1)
4) in a common PLS model for water, cider and HFCS together it seems that the influence of particular level of adulteration is canceled out. Quantification of few mixtures of adulterants in various proportions would allow to estimate a true robustness of the model
5) measurement repetition is expected to correct strange fluctuations of absorbances at 10% and 60% for water in Fig. 2
6) It is not clear, on the basis of what parameter do the authors believe that “The adulteration level in SBH including 10% was identified”, no statistical prove
7) Prediction curve (Fig. 5) is extrapolated to minus values, what has no sense
8) L.18 (abstract) – to quantify the purification of the honey samples - rather contamination
9) numbering of paragraphs must be corrected
Author Response
The responses to the reviewers' comments are in the attached pdf file.
Author Response File: Author Response.pdf
Reviewer 3 Report
The manuscript “Identification of Stingless Bee Honey Adulteration using Visible-Near Infrared Spectroscopy Combined with Aquaphotomics” by Muna E. Raypah et al, describes the characteristic of pure and adulterated SBH has been studied using visible and near-infrared spectroscopy. Each adulterant resulted in a change in the spectral pattern of honey and explained by the interaction of adulterant with the chemical structure of honey. This will be of interest to readers concerned with food safety and the effects of doping on chemical structure and spectra. I recommend the manuscript to be accepted for publication after miner revision.
Listed below are my comments and questions.
- Why there was a controlled apple cider of honey adulterated with cider designed? Does anyone add apple cider to honey, or does the trials suggest anything special?
- In L380, what does ice-like clusters of water mean? This result needs to be discussed in more detail
- Labels in many chapters are wrong, for example, L110, L114, L119, L125, L129, L140 and L162 are all section 1.1. The label of Results and Discussion and the internal subtitle also have this error.
Author Response
We would like to express our sincere gratitude to the editor of Molecules Journal for allowing us to improve our manuscript for potential publication in the journal and to the reviewers who have critically evaluated our work and given constructive comments to enhance the technical merit of the manuscript. We have tried our best to address all the technical issues raised by the reviewers and we are ready to make any further modifications to the manuscript if it is required. All the corrections are written in red font in the revised manuscript. Below is a point-by-point response to the comments:
Reviewer # 3:
Comment 1: Why there was a controlled apple cider of honey adulterated with cider designed? Does anyone add apple cider to honey, or does the trials suggest anything special?
Response 1: The reason behind using apple cider vinegar as an adulterant in SBH: Stingless bee honey has a high-water content, slight sweetness, acidic flavour, fluid texture, and slow crystallization [21]. Honey produced by stingless bees (Melipona sp. and Trigona sp.) is recognized for its unique sour taste and odour [22]. Limited availability and the high price of SBH are the main culprits in increasing interest in its adulteration. Based on the local beekeeper report, adulteration of SBH involves dilution with water to increase the volume of the honey to fraudulently increase income. In certain cases, cheaper honey is blended with a sour-tasting liquid such as vinegar to create a sour taste that resembles that of SBH, and then market at a high price commensurate with the pure SBH [5]. A text is added and highlighted on PAGE 3 in the revised manuscript to show why the apple cider vinegar was used as an adulterant for SBH.
Comment 2: In L380, what does ice-like clusters of water mean? This result needs to be discussed in more detail
Response 2: The molecular structure of ice-like clusters has very stable structures, formed by a very small amount of non-hydrogen bonded water (monomeric species), and predominantly bound by one hydrogen bond at the periphery and two in the center. We have explained that sugars and other macromolecules typically generate this kind of water structure, and supported this claim with two references: one about sugars in general [23], and one about sugars in honey [24]. An explanation about the molecular structure of ice-like clusters is added and highlighted in the revised manuscript on PAGEs 22-23.
Comment 3: Labels in many chapters are wrong, for example, L110, L114, L119, L125, L129, L140 and L162 are all section 1.1. The label of Results and Discussion and the internal subtitle also have this error.
Response 3: This comment is also addressed by Reviewer 2# in comment 9. The numbering of paragraphs in the submitted word document was correct. The numbering of paragraphs is appeared not correct in the built pdf by the journal system. The numbering of paragraphs is now corrected in the built pdf of the revised manuscript.
References
- Pimentel, T.C., et al., Stingless bee honey: An overview of health benefits and main market challenges. Journal of Food Biochemistry, 2021: p. e13883.
- Chan, B.K., et al., Physical properties, antioxidant content and anti-oxidative activities of Malaysian stingless kelulut (Trigona spp.) honey. Journal of Agricultural Science, 2017. 9(3): p. 32-40.
- Giangiacomo, R., Study of water–sugar interactions at increasing sugar concentration by NIR spectroscopy. Food Chemistry, 2006. 96(3): p. 371-379.
- Bázár, G., et al., Water revealed as molecular mirror when measuring low concentrations of sugar with near infrared light. Analytica chimica acta, 2015. 896: p. 52-62.
Round 2
Reviewer 1 Report
please kindly revise followed my commemt om attachment
Comments for author File: Comments.pdf
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
no more comments
Author Response
No more comments given by the reviewer 2.
