scholarly journals Discrimination of mineral waters using near infrared spectroscopy and aquaphotomics

2014 ◽  
Vol 68 (2) ◽  
pp. 257-264 ◽  
Author(s):  
Jelena Muncan ◽  
Lidija Matija ◽  
Jovana Simic-Krstic ◽  
Srecko Nijemcevic ◽  
Djuro Koruga

Despite that water is one of the most studied materials today its dynamic properties are still not well understood. Water state in human organism is of high importance for normal healthy functioning of human body. Different kinds of water are usually classified according to its present solutes, and concentrations of these solutes, but though it is known that water molecules can form clusters around present solutes, classification of waters based on types of water molecular organization and present clusters is not present in current literature. In this study we used multivariate analysis for classification of commercial mineral waters based on their near infrared spectra (NIR). Further, we applied Aquaphotomics, a new approach for interpretation of near infrared spectra of water, which gives insight into organization of water molecules in each of these waters.

2016 ◽  
Vol 689 ◽  
pp. 143-147 ◽  
Author(s):  
Alfred A. Christy

β-cyclodextrin, like other carbohydrates has a tendency to adsorb water molecules and the properties are attributed to the hydroxyl groups in the molecules. β-cyclodextrin, the cyclic oligomer of glucose has a hydrophobic interior and hydrophilic exterior. The cyclic structure favours the formation of hydrogen bonds between the OH groups on the adjacent glucose units and affects the formation of hydrogen bonds with water molecules. The hydoxyl groups engaged in hydrogen bondings can be eliminated at high temperatures and the adsorption properties of the dehydrated β-cyclodextrin will depend on the new functional groups formed. The aim of the report is to discuss the issue of the water adsorption properties of free and dehydrated β-cyclodextrin. Dry β-cyclodextrin and dehydrated β-cyclodextrin at temperatures 250, 300 and 350 °C were allowed to adsorb water from a humidity controlled air environmennt and the evolving near infrared spectra were measured using a near infrared spectrometer equipped with a transflectance accessory. The near infrared spectra in the region 10,000-4000 cm-1 and their second and fourth derivative profiles were used in studying the variation in the adsorption characteristics of dehydrated β-cyclodextrin. The results of the analyses show that the adsorption of water by β-cyclodextrin decreses at 300 °C compared to 200 and 250 °C. Dehydration forms more of the ethereal type-O-bonds in the molecule and explains the decrease in the water molecular adsorption at higher dehydration temperatures.


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