Multivariate study of spectral data of oils

In this paper the study of structural differences and thermal degradation of edible oils during heating is presented. The study is performed on five types of vegetable oil: extra virgin olive oil, pomace olive oil, sunflower, canola and palm oil. The oils were measured by Raman spectroscopy. This method brings advantages as rapidity, independence on chemicals, provides specific information on chemical composition and structure of material and is able to detect structural changes. For the processing of large data sets multivariate analytical method as Principal component analysis and Cluster analysis are applied to find the patterns within the data. The evaluation of process of thermal degradation is also based on the major decomposition product of oxidized linoleate appearing in spectra via band 1640 cm−1. Mathematically processed data indicate the least effect of heating for olive oils, the greatest degradation and loss of unsaturation for sunflower oil

Measuring the lactose content in milk

Raman spectroscopy has become a powerful and popular tool for food systems analyses lately. Based on characteristic vibrations of the studied material, the information on its content and structure can be answered. In the paper, Raman spectroscopy is studied for a purpose of lactose content in milk assessment. Lactose, the milk disaccharide, in a human organism decomposes during digestion by the act of enzyme lactase to more easily digestible monosaccharides – glucose and galactose. The lack of enzyme lactase causes symptoms of lactose intolerance what limits lactose-intolerant individuals in the intake of milk and dairy products. Lactose-free products in the diet can be a solution. Raman spectroscopy offers rapid measurement independent of the number of chemicals and other in the paper listed benefits. Raman spectra of lactose, glucose and galactose exhibit enough differences to distinguish the content of lactose in milk. C-O-H bending mode at 1087 cm-1 is used for lactose quantification. The method accuracy for measuring content of lactose was tested on dried milk droplets. Evaluation of the spectroscopic data was related to two different substances - phenylalanine contained generally in the milk and crystal violet used as an internal standard