Impact of yeast sediment beta-glucans on the quality indices of yoghurt

The objective of the study was to investigate the potential application of beta-glucans obtained from yeast sediment resulting from the manufacture of local Viorica wine (2018 harvest). To determine the amount of beta-glucans in the yeast sediment, two were used: the calculation method and the laboratory method, obtaining similar quantities, 29.92 ± 0.47 and 28.17 ± 0.32 respectively. The beta -glucans obtained were incorporated in various concentrations (0.1%; 0.2%; 0.3%; 0.4% and 0.5%) in the yogurt obtained from skimmed milk. The effect of beta-glucan addition on the physicochemical properties of freshly prepared yogurts was investigated. The addition of beta-glucans positively influenced the formation of the gel relay resulting in a decrease in the fermentation time of yogurt. The final pH point of 4.5 was reached one hour earlier (in 4 hours) compared to the control sample (in 5 hours). The results showed that there are no significant changes in physicochemical properties (titratable acidity, pH, viscosity and syneresis). The results obtained report that beta-glucans can be used as a thickening agent for low-fat yogurts by shortening the fermentation period and not essentially changing the sensory characteristics. Experimental results showed that the glycemic index of yogurt samples with the addition of beta-glucans have similar values in the range of 28-30. Respectively, the yogurts under study are attributed to food category with low glycemic index