Production of Yoghurt Analogue from Soy Milk and Different Fermented Cereal Based Water Filtrates (Omi ogi)

Abstract

Yoghurt analogue was produced by fermenting soy milk with different selected fermented cereal based filtrates. The water filtrate was obtained from fermented 100% Zea mays (yellow variety) 100% Quality Protein Maize (yellow variety), 100% Sorghum (red variety) and 100% Millet (light cream variety). The pH, titratable acidity (TTA), microbial load, microbial type, proximate composition and mineral content of the yoghurt samples were determined. The samples were also subjected to sensory evaluation. The pH ranged from 4.68 in soy milk fermented with millet to 5.20 in soymilk fermented with quality protein maize. Total viable count was highest in soymilk fermented with sorghum filtrate (9.08 log cfu/ml) while Lactic acid bacteria count was highest in soymilk fermented with millet filtrate (7.50 log cfu/ml). Lactobacillus plantarum, L. fermentatum and Saccharomyces cerevisiae were found to occur in all the four yoghurt samples. There was no significant difference (p > 0.05) in the moisture content of all the yoghurt samples. Soymilk fermented with sorghum filterate contained the highest crude protein (3.57%) while the highest fat content was recorded in soymilk fermented with yellow maize filtrate (2.97%). Highest calcium and magnesium content was found in soymilk fermented with millet filterate. Commercial yoghurt was the most preferred in all the sensory attributes tested followed by soy milk fermented with millet filterate. All the yoghurt samples were accepted organoleptically. Soymilk and fermented cereal filterate could serve as good alternative to the expensive soymilk and commercial starter for production of good quality yoghurt analogue. Filtrate from sorghum appear to be the best starter for soy yoghurt production in terms of nutrients content while filterate from millet was most accepted by sensory panelists.

Keywords: Yoghurt, soymilk, maize, millet, sorghum, filtrate.