Production of yogurt analogs from peanut milk (extract) using microbial transglutaminase and two different starter cultures

This study produced and analyzed peanut milk yogurt analogs made with microbial transglutaminase (mTGase), two different starter cultures (an EPS and a non-EPS producer), and additional peanut pulp to solve low viscosity and textural problems in peanut milk yogurts. The EPS starter culture was used to determine whether it could help solve these problems. Six yogurt analogs were produced, three with YC350 and three with YoFlex starter cultures. SDS-PAGE analysis showed that the intensity of protein bands decreased with increasing enzyme concentration. The microstructure of yogurt analogs made with the EPS starter culture had a less porous, tighter matrix and creamier structure. Diacetyl and acetaldehyde, important volatile compounds of yogurt, were also present among the 34 volatile compounds identified. In sensory analyses, yogurt analogs produced with non-EPS cultures received higher scores, especially in appearance, odor, and consistency. The number of yogurt bacteria reached 8 log10 cfu/g, which shows that peanut milk is a suitable substrate for growing yogurt bacteria. No significant changes occurred in water holding capacity or syneresis during storage. Among the two yogurt samples (C and F), EPS-added yogurt yielded better results regarding firmness. However, the shelf life of peanut milk yogurt analogs was 14 days.