The purpose of the article is to highlight the results of research on the parameters of the fermentation process of apple juice to obtain new types of natural fermented juices based on it. The aim of this study was to evaluate the effect of the lactic acid bacterium Lactobacillus acidophilus on the taste profile and amount of macro- and microelements of fermented apple juice. The conducted research is aimed at increasing the biological value of apple juice by fermentation of L. acidophilus. Juice fermentation was carried out in parallel with the addition of glucose at the beginning of fermentation and without additional glucose. Magnesium, glucose, and potassium concentrations were measured according to the methodology developed by FILISIT-DIAGNOSTIKA LLC. The quantitative determination of vitamin C was carried out by the method of iodometric titration, and the acidity was measured by the potentiometric method. The Wilcoxon test was used to compare mean values and identify significant differences (р ˂ 0.05) between groups. Based on the main data obtained, it was concluded that the concentration of magnesium increases when using juice without the addition of glucose, but no changes in the magnesium index were observed in juice with glucose. In addition, when examining the content of vitamin C, it was determined that the concentration of vitamin C increased when using juice with the addition of glucose, but no changes were observed in the juice without added glucose.
The level of glucose before and after fermentation did not change in both experiments. The potassium content in the juice with the addition of glucose is lower. The indicator of total acidity increased when using juice without the addition of glucose, but there were no changes in juice with glucose. These results may be useful for determining the contribution of L. acidophilus as an individual component in fermented juices.