LUMINESCENT PROPERTIES OF MILK OF DIFFERENT FAT CONTENT DURING SOURING

Abstract

The use of optical spectral methods can help in solving problems that arise during the processing of milk and dairy products. Traditional analytical methods (for example, physico-chemical measurements, sensory analysis, chromatography) are relatively expensive, time-consuming and require chemicals and sophisticated analytical equipment, as well as qualified personnel. There is a need to develop faster and less costly ways to monitor changes in the quality of milk and other dairy products during processing and storage. Many non-destructive and non-invasive instrumental methods are available for embedded and online monitoring of food products. These include fluorescence spectroscopy, reflective spectroscopy of the middle and near infrared range, nuclear magnetic resonance, and so on. (Research purpose) The research purpose is studying the photoluminescent characteristics and parameters of milk of various fat content during its souring. (Materials and methods) Measurements of the spectral characteristics of milk excitation in the range of 200-500 nanometers were performed on the Fluorat-02-Panorama spectrofluorimeter. (Results and discussion) An increase in luminescence intensity was noted at an excitation wavelength of 442 nanometers and its decrease at 262 nanometers after a given period of time for a fat content of 3.2 percent. It was determined that for a fat content of 1.5 percent at an excitation wavelength of 262 nanometers, the trend persists, but at an excitation wavelength of 442 nanometers, on the contrary, the luminescence intensity decreases, which requires clarifying experiments. (Conclusions) The obtained results indicate the dependence of milk souring and changes in luminescence intensity over time. It was stated that this observation can be the basis for further research in the field of quality control of dairy products by non-destructive testing based on optical methods.