Probiotics screening from selected Nigerian prebiotics: Alternative starter culture sources for yoghurt production

Abstract

The rise of functional foods has expanded food production, offering not just essential nutrition but also potential health and longevity benefits. This study aimed to identify probiotics from common Nigerian fermented foods as potential starter cultures for yogurt production. Ten local fermented food were screened for suitable starter culture(probiotics) for yogurt production, including fresh milk from cow (CM), sheep (SM), and goat (GM), as well as pap made from maize, millet, sorghum, cassava products (garri, fufu, and lafun), and Kunuzaki. Probiotic isolates with desired characteristics underwent tests for tolerance to acidic pH and bile conditions; antioxidative properties. Test yogurt was produced using Lactobacillus (LAB) isolates and physicochemical and organoleptic scores were determined for the yogurt samples. LAB species from CM, SM, and Lafun samples showed tolerance to both acidic pH (pH 3.0) and 0.5 percent bile. CM isolates exhibited strong antioxidant effects comparable to vitamin C. Yogurt samples had pH ranging from 4.77 to 5.45 and titratable acidity from 5.56 to 8.06. Sensory characteristics of the test yogurt did not significantly differ from commercial yogurt (p ≤ 0.05). Thus, probiotics (LAB) from common Nigerian fermented foods like CM, SM, and lafun could serve as cost-effective, nutrient-rich alternatives for yogurt starter cultures.