Evaluation of the Suitability of Tigernut Milk and Tigernut-Cow Composite Milks for Yoghurt Production

Abstract

The cost of animal milk used in yoghurt production in Nigeria has continued to rise, making the price of yoghurt to become prohibitive. This study investigated the suitability of tiger nut milk for yoghurt production. Five milk formulations prepared from tiger nut milk and cow milk were used to produce yoghurts. pH and titratable acidity (TA) of the milks and yoghurts were determined. The yoghurts were assessed for total plate count (TPC), total fungal count (TFC), fat content and sensory properties. Sensory properties were evaluated by a 10-man taste-panel using a 5-point hedonic scale. pH values of the yoghurts ranged from 3.94 – 4.68. TA values ranged from 0.56 – 0.64. TPC of the yoghurts ranged from 1.0 x 102 – 1.3 x 103 cfu/ml while TFC ranged from 0.1 x 101 – 0.3 x 101. The microbial counts of the yoghurt samples were within acceptable safety limits. The yoghurts were generally acceptable to the panelists. There were significant (P < .05) differences in the sensory scores for appearance, taste, texture, and overall acceptability. Tiger nut-cow milk (75:25) yoghurt had the highest appearance and taste scores while tiger nut milk (100) yoghurt had the highest texture and overall acceptability scores. Tiger nut milk (100) yoghurt was the most preferred yoghurt with an overall acceptability score of 4.8±0.42 followed by tiger nut-cow milk (75:25) yoghurt. Yoghurts analysed had fairly high fat contents. The study showed that tiger nut milk and tiger nut-cow milk composites could be used as alternatives to cow milk for yoghurt production.