Preparation and characteristics of lactic acid fermented cowpea milk

Four Lactobacilli were isolated from both commercial cowmilk yoghurt ("Fan" yoghurt) and "wara", a West African soft cheese. They were identified as Lactobacillus acidophilus ("Fan" yoghurt), L. plantarum, L. brevis and unidentified Lactobacillus spp. ("wara"). L. acidophilus and L. plantarum were chosen as starter organisms for the production of a yoghurt-like product from cowpea milk. There was a decrease in the final pH and an increase in the titratable acidity of the cowpea milk samples at the end of the fermentation period. The crude protein, total ash, calcium, potassium and phosphorus values increased in the fermented cowpea milk, while a decrease was obtained for the lipid, moisture and crude fibre contents. A decreasing trend was noted in the phytic acid and trypsin inhibitor of the cowpea flour when processed into milk, followed by a further reduction at the end of fermentation. Consumer acceptability of the cowpea yoghurt varied, with preference being given to the banana and strawberry flavoured samples.