Sensory and nutritional evaluation of soy yoghurt fermented with indigenous lactic acid bacteria

Anya V. C., Ugboma C. J. and Nrior R. R.

Microbiology Research International
Published: October 22 2024
Volume 12, Issue 4
Pages 110-115

Abstract

This study evaluated the sensory properties and nutritional composition of soy yoghurt produced using a combination of indigenous lactic acid bacterial strains, focusing on improving protein content, viscosity, and overall consumer acceptability. Lactic acid bacteria were isolated from 24-hour fermented cow milk using the pour plate method and incubated at 37°C for 48 hours. The isolates were characterized based on cultural, morphological, physiological, and biochemical identification. Eleven (11) treatments were prepared from combinations of starter cultures. The soy yoghurt was fermented at 30ºC for 12 hours and then stored at 4ºC for proximate analysis and sensory evaluation. The proximate composition of soymilk (moisture, fat, carbohydrate, ash content, and protein) was 91.82%, 8.07%, 14.95%, 0.80%, and 5.28%, respectively. The evaluation of the soy yoghurt's nutritional quality showed that the fat (8.49%), moisture (91.75%), ash (3.75%), and protein content (7.95%) were higher than those of a popular dairy yoghurt brand (8.38%, 84.39%, 1.35%, and 2.45%, respectively). Sensory evaluation revealed that the consistency of SM+Laf2+Lal was preferred to CY. The soy yoghurts produced were creamy in color, with different flavors depending on the type and ratio of the bacterial combinations used. This study demonstrates that soy yoghurt produced using starter cultures from nunu competes favorably with popular dairy yoghurt brands. Furthermore, soy yoghurt, with its high protein content and probiotic properties, could be introduced into public health programs, particularly in regions where dairy consumption is limited or unaffordable.

Keywords: Plant-based yoghurt, soymilk, protein content, carbohydrate content, ash content, sensory evaluation.

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