Organoleptic properties and quality of yoghurt produced from goat milk

Abstract

Goat milk samples were collected from the Research Farm of Abubakar Tafawa Balewa Uinversity, Bauchi, Nigeria were used in investigating the shelf life of fresh and pasteurized milk as well as organoleptic properties of four yoghurt samples produced from them. Sensory evaluation was done on the yoghurt produced from the goat milk using different flavors and included vanilla flavored goat milk yoghurt (VFGMY), straw berry flavored goat milk yoghurt (SFGMY), pineapple flavored goat milk yoghurt (PFGMY) and unflavored goat milk yoghurt (UFGMY). The fresh and pasteurized milk stored at 5 0C for 0, 24, 48 and 72 hours had microbial load of 2.5 x 10 2vs 0.0, 2.8 x 10 3 vs 40.0, 3.2 x 10 3 vs x 90.0 and 4.5 x 10 3 vs 2.3 x 10 2 cfu /ml respectively. The microbial loads of those stored at 35 0C for the same periods were 2.5 x 10 2 vs 0.0, 3.6 x 10 3 vs 80.0, 5.0 x 10 3 vs 2.7 x 10 2 and 6.9 x 10 3 vs 4.3 x 10 2 cfu /ml respectively. The results also revealed that VFGMY, SFGMY and PFGMY were significantly inferior in quality to UFGMY with respect to appearance (p<0.05), taste, aroma and overall acceptability (p<0.001). Conversely, there were no significant differences between the flavored yoghurts and the control (UFGMY) in terms of flavor and color. It was concluded that flavoring goat milk after heat treatment had no influence on the off flavor in the milk. The UFGMY was more preferred than the other three flavored yoghurts in their organoleptic properties. However, the shelf life of goat milk improved greatly when pasteurized and stored at 5 0C.


Animal Production Research Avancees Vol. 3 (1) 2007: pp. 18-22