Research of an impact of the low-frequency ultrasound effects on the processes of wine materials fermentation

The complexity of the grape wines production consists in the length and complexity of the technological process; therefore, strict management of all operations is required. Modern technologies are focused on reducing the time of production, including the process of fermentation of wine materials while ensuring the high quality of finished products. We propose to intensify the process of fermenting wine wort under the influence of ultrasound. Ultrasonic cavitation leads to the formation of free radicals, local turbulence,volutin and microturbulence. Liquid microcirculation can improve fluid transportation and reduce mass transfer resistance in heterogeneous systems. Cavitation can cause changes at the molecular level, increasing mass transfer and minimizing process time while ensuring product safety and quality. The use of ultrasound of different power (189 and 315 Watt) and processing time (from three to five minutes) showed positive effects in the intensification of alcoholic fermentation, changes in acidity, and caused changes in yeast cells. After five days of fermentation, the mass fraction of alcohol in the wine wort increased by 20.7 - 88% (depending on the ultrasonic treatment mode), after 10 days of fermentation, the alcohol content in the experimental samples exceeded the alcohol content in the control sample by 4.8-5.8%. The intensity of the increase in acidity after five days of fermentation made up from 2.4 to 19.3%. Ultrasonic processing of the mash before fermenting the wort increases the activity of the yeast, accelerating the technological process. The positive effects of ultrasonic processing established in the course of research allow to conclude that further research is needed in this direction.