ISSN 2375-1177
African Journal of Agriculture and Food Security ISSN: 2375-1177 Vol. 11 (2), pp. 001-019, February, 2023. © International Scholars Journals
Full Length Research Paper
QUALITY ASSESSMENTS OF YOGHURTS AND YOGHURT- LIKE PRODUCT FROM LOCAL PLANT MATERIALS (Cajanus cajan, Vignia ungiculata and Vignia subterranean)
Larry Williams,1 and Kelvin Smith2
1Department of Food Science and Technology, Abia State University, Uturu
2Department of Pure and Industrial Chemistry, Abia State University, Uturu.
Abstract
In recent years, research has been focused on creating foods with higher protein quality through the use of mixtures of cereals and legumes that are thought to be nutritionally balanced due to challenges with food security in underdeveloped nations.In this way, underutilized regional foods including Cajanus cajan (Fiofio), Vignia ungiculata (Akidi oji), and Vignia subterranea (Okpa) were blended with local plant raw materials to create yoghurts. Also, commercial Cowbell milk was used as a control in the yoghurt preparation. As a potential replacement for commercial starter cultures that contain lactic acid-producing bacteria, the investigation also evaluated the impact of utilizing sorghum and millet steep waters as starter cultures (Lactobacillus bulgaricus and Streptococcus thermophilus). Twenty-twoyoghurt samples were prepared (A1234, B1234, C1234 D, E123, F1234 and G123. They were subjected to proximate, phytochemicals, minerals, vitamins, chemicals, microbial analysis as well as sensory evaluation with a view of understanding the consumer acceptability of the products. Commercially acceptable yoghurt brand- Hollandia yoghurt was also analyzed and used as overall control (sample D). The data generated were analysed using one-way ANOVA followed by Tukey’s post hoc test and significant difference set at (p<0.05). The result indicated the presence of alkaloids (0.3 - 1.2mg), flavonoids (0.7 - 2.6mg), saponin (0.1 - 0.8mg), tanins (0.2 - 1.2mg) and oxalate (0.1 - 0.5mg). Vitamins, calcium (6.0 - 19.33mg), potassium (1.2 – 24.59mg), magnesium (0.70 - 6.65mg), sulphur (0.0 – 0.1mg) and phosphorus (78 – 166) were at acceptable levels. These and other parameters studied varied significantly (p<0.05) for samples fermented with commercial starter culture, sorghum and millet steep water. The microbial result revealed that total viable count (TVC) ranged from 1.0 x 105 minimum to 7.2 x 105 maximum, pathogenic bacteria was not seen (nil). Both total viable count (TVC) and pathogenic bacteria were in a tolerable level for the three cultures. The result showed significant differences (p<0.05) in aroma, appearance, taste, texture and overall acceptance among the different yoghurt samples and fermented cultures. Consequently, yoghurt was successfully produced from local plant raw materials and there is possibility of using sorghum and millet steep water as a substitute for commercial starter culture.
Key words: Yoghurt, quality assessment, sorghum, millet steep and commercial starter culture.