Physicochemical, Microbiological, Sensory Properties and Storage Stability of Plant-based Yoghurt Produced from Bambaranut, Soybean and Moringa oleifera Seed Milks

Abstract

The physicochemical, microbiological properties and sensory characteristics of plant-based yoghurt (PBY) produced from bambaranut, soy and Moringa oleifera seed milks were studied. Milks were produced from bambaranut, soybean and moringa oleifera seed and then fermented using Lactobacillus bulgaricus and Streptococcus thermophilus to produce the yoghurts. These yoghurts were stored at 6 °C for 14 days (2 weeks) and their quality monitored. The study revealed that the physicochemical parameters; Peroxide value, Total solid non-fat (TSNF), Total titratable acidity (TTA), Total solids, Viscosity and pH of these yoghurt samples were within the acceptable standards from zero to 14 days of storage. Peroxide value ranged from 10.00-11.00 mEq/kg; 10.24-11.12 mEeq/kg and 10.40-11.30 for 0, 7 and 14th day of storage respectively. TSNF ranged from 12.06-14.29 %; 12.56-14.78 % and 12.96-15.19 % for 0, 7 and 14th day of storage respectively. TTA ranged from 0.65-0.78 %; 0.86-0.99 % and 1.08-1.18 % for 0, 7 and 14th day of storage respectively. Total solids ranged from 16.25-17.91 %; 17.00-18.51 % and 17.34-19.02 % for 0, 7 and 14th day of storage respectively. Viscosity ranged from 526.43-659.26 cP; 476.47-609.28 cP and 428.15-568.90 cP for 0, 7 and 14th day of storage respectively. The pH ranged from 4.00-4.50; 3.66-4.27 and 3.21-3.85 for 0, 7 and 14th day of storage respectively. Results showed that these yoghurt samples from zero to 14 days of storage were microbiologically stable and were found to be within the acceptable standard specified by NAFDAC and Codex Alimentarius. The sensory properties revealed that cow milk yoghurt was liked very much in terms of overall acceptability followed by sample 577 (50 % Soymilk +35 % Bamabara milk + 15 % Moringa seed milk) which was liked moderately and the other samples which all were generally accepted.