Production of Yoghurt from Milk Extract of Tigernut (Cyperus esculentus) Using Lactic Acid Bacteria Isolated from Locally Fermented Milk (Nono)

Aims: The aim of the study was to produce yoghurt from milk extract of tigernut (Cyperus esculentus) using lactic acid bacteria isolated from locally fermented milk (nono) with specific objectives of comparing the proximate composition of tigernut- yoghurt with a popular yoghurt brand in Keffi, Nasarawa State and determining the acceptance level of both products based on sensory evaluation.

Study Design: A comparative study of tiger nut yoghurt and a popular yoghurt brand in Keffi, Nasarawa State, Nigeria.

Place and Duration of Study: Department of Microbiology, Nasarawa State University Keffi, Nasarawa State, Nigeria, between December 2016 and October 2017.

Methodology: Belewu and Abodunrin’s method was used for the extraction of milk from tigernut obtained in the market. The presumptive isolates from the locally fermented milk (nono) were confirmed using the API rapid identification test kit and sub-cultured to obtain pure isolates of lactic acid bacteria. The extracted tigernut milk was fermented with Lactobacillus bulgaricus and Streptococuss thermophilus in an anaerobic chamber and the resulting yoghurt was subjected to quantitative proximate analysis and sensory evaluation.

Results: The result obtained from the proximate analysis showed no significant difference (p=.05) between the ash, carbohydrate and moisture content of all yoghurt samples but there were significant differences (p=.05) between the protein, crude fibre and fat content of both Samples. The pH of all samples was between 4.0-4.5 and titra-table acidity between 0.91-0.95. Also, the sensory evaluation result showed no significant difference (P=.05) in texture and taste except for appearance, aroma, consistency and overall acceptance

Conclusion: This study revealed that tiger nut milk can be a good substitute to cow milk for the production of yoghurt.