South Ural State University received patent for a producing method of yogurt product with increased content of exopolysaccharide kefiran. Researchers of the SUSU School of Medical Biology determined that electrophysical exposure with the use of ultrasound positively influences on composition and viscosity of fermented milk products, and as a result on accumulation of biologically active components.
Initially, interest of the researchers of the School of Medical Biology was connected with determining healthfulness criteria for fermented milk products in general. First series of research of kefir ferments, used by different manufacturers, were carried out using kefir and kefir-based beverages. The obtained results excited scientists’ interest, therefore a decision to extend the research area by complementing consumer properties with dynamics of accumulation of biologically active substances was made.
“With a series of experiments, a group of scientists of the School of Medical Biology obtained and proved data indicating on the fact that ultrasound cavitation, as an effect of electrophysical exposure, can create specific conditions for development of fermenting microflora, which is used as the main constituent in technology of kefir, yogurt and other fermented milk drinks,” says Irina Potoroko, Candidate of Engineering Sciences, Professor, Head of the Food and Biotechnology Department of the SUSU School of Medical Biology. “Initial effects of this phenomenon we observed in changes of viscosity of fermented milk drinks and tightening of curds, but we never connected this with criteria of its healthfulness. Then the research, along with studying the experience of foreign colleagues related to influence on development of microflora of external and internal factors, made us pay closer attention to the reasons for changes of the product’s viscosity under the exposure of ultrasound.”
It is known that one of the factors of changes connected with product’s viscosity is the ability of some microorganisms to form and accumulate specific substances which act like viscosifiers. Example of this is exopolysaccharide kefiran – a substance produced by lactic-acid fermenting bacteria, including Lactobacillus Bulgaricus, into external medium, which influences the curd structure of yogurt products.
“While identifying this polysaccharide, we discovered its one more very important property, continues Irina Potoroko, to influence on the state of human organism, its metabolism processes, particularly on the factors that allow minimizing the risk of development of different diseases, and enhance digestion processes. We got interested with the possibility to use ultrasound cavitation in order to regulate the process of accumulation of kefiran.”
South Ural scientists determined optimal regimes, using which it is possible to obtain the necessary concentration in kefiran accumulation; this became the basis for receiving patent for a unique innovation method of manufacturing yogurt products with increased content of polysaccharide, which has no analogues in the world.
“I think this research area will have a good perspective. Currently we consider the possibility of collaboration with foreign colleagues-biotechnologists from India and Iraq, particularly with the Warangal National Institute of Technology (India). Together we will try to experimentally check the influence of some factors which, aside from electrophysical exposure, will help activating accumulation of kefiran in fermented milk products,” says Irina Potoroko.
Final stage of the SUSU scientists’ research will be a clinical evidence of physiological efficiency of consuming fermented milk products, and release of a trial batch of the healthful yogurt with increased content of kefiran for mass consumption in cooperation with one of milk processing plants of the Kurgan region.
