Fatty acid profile and rheological and microbiological characteristics of yogurts produced by different cultures using power ultrasound compared to homogenization

Ultrasound, considered a green technology, holds great potential in the dairy industry. It has key benefits over conventional homogenization and is increasingly important, particularly for fermented milk technology. Thus, this study investigated how this technology affects the rheology, microbiology and fatty acid profile of yogurts produced with EPS-producing or non-EPS-producing starter cultures. Ultrasound generally increased S. thermophilus viability in yogurt produced with both cultures, while it increased L. bulgaricus in yogurt produced with only non-EPS-producing starter culture. Ultrasound also increased viscosity by up to 35 % and consistency by up to 50 % in yogurt produced with non-EPS-producing culture, and increased water-holding capacity at the end of storage in samples produced with both cultures. Ultrasound reduced the atherogenic and thrombogenic indexes and saturated fatty acids at the end of storage, whereas it increased polyunsaturated fatty acids in yogurt manufactured with both cultures at the middle and end of storage.