Microbiological, physicochemical and sensory evaluation of fermented milk from blends of tigernut, soy and groundnut milk

The study was aimed at producing an acceptable, health promoting and affordable yoghurt analogue from blends of tigernut-, soy- and groundnut milk. Different blends of tigernut, soy and groundnut milk (1: 1: 1; 1: 2: 1; 1: 1: 2; and 2: 1: 1) respectively were formulated and inoculated with 2% (w/v) commercial starter culture containing Lactobacillus bulgaricus; L. acidophilus and Streptoccus thermophilus). Samples were incubated at 45 degrees C for 6h and then for 24h. Thereafter, samples were pasteurized at 65 degrees C for 30 minutes and subsequently refrigerated for 21d at (4 +/- 1 degrees C). Samples were subjected to microbiological analysis, physico-chemical and sensory evaluation at different stages of preparation and storage. Results show that the Lactic acid bacteria (LAB) count increased from (3.6 x 10(5)-9.9 x 10(6)) to (8.4 x 10(5) - 10.0 x 10(6)) in all the samples during the first 7 days but it decreased thereafter. TTA increased from 0.24 - 0.25 to 0.58 - 0.94 after 21d of refrigerated storage. Responses elicited from tasters reveal that there was no significant difference in taste, flavor appearance and overall acceptability of the fermented milk samples (p > 0.05). The study has established that acceptable and safe fermented drink could be produced from different blends of milk from tigernut, soybeans and groundnut.