Abstract:
Yoghurt is among high value dairy products that are cultured using live
organisms and termed as a probiotic carrier. Yoghurt was flavoured using
coffee extract to allow diversification of dairy cultured products. In this
research, the potential effect of coffee extract on the physicochemical and
sensory properties of coffee flavored yoghurt was studied. A complete
randomized design was used where four treatments were assigned to twelve
experimental units. The treatments were prepared by addition of coffee
extract to the yoghurt in the ratio of 0.0% (control), 0.1%, 0.2%, and 0.3%.
The treatments were made in three replicates. The samples were analyzed
for physicochemical properties and sensory evaluation. Physicochemical
properties analyzed included pH, titratable acidity, viscosity and syneresis.
Sensory evaluation was conducted by eighteen untrained panelists who were
consumers of yoghurt. All were drawn from both students and the staff in
the Institute of Food Bioresources Technology, using a nine-point hedonic
scale. Data was analyzed by use of ANOVA, means separated by fisher’s LSD
at p<0.05 level of significance. From the findings, pH gave readings between
4.45±0.0 and 3.92±0.0. Results for titratable acidity was between 0.78±0.0
and 0.93±0.0. Viscosity ranged from 3241.7±62.9 to 2041.7±14.4, while
results for Syneresis were between 8.93±0.5 and 25.33±0.6. Significant
differences were recorded in all physicochemical properties evaluated in this
research, while sensory scores ranged from 6.5 to 8.5 and significance
difference was recorded in all sensory parameters used except in texture and
aroma. Physicochemical properties of yoghurt were found to influence the
quality and overall acceptability of yoghurt by the consumers.
