Original scientific paper
The influence of sterilized goats and cow's milk on yoghurt quality during storage
Rajka Božanić
orcid.org/0000-0002-3387-0315
; Prehrambeno-biotehnološki fakultet, Pierottijeva 6, 10000 Zagreb
Ljubica Tratnik
Olivera Marić
Abstract
In this work the influence of sterilized goat's and cow's milk and theirs mixture (1:1) on yoghurt quality during nine days of storage at +8 °C, were investigated. The viscosity of cow's milk yoghurt was a lower during all nine days of storage, while the viscosity of yoghurt from mixed milk was greater. The decrease of pH value during goat's yoghurt samples was faster as in cow's yoghurt samples. The most lactic acid was in cow's yoghurt, and the least in goat's yoghurt during storage. Viable count was maximal after 24 hours of storage in all samples (logNmax = 9.839-9.668). During nine days of storage the ratio between lactobacilli and streptococci was changed in all yoghurt samples, respectively. In the samples cow's and mixed yoghurt streptococii died faster than lactobacilii. Only in goat's yoghurt lactobacillii died faster until sixth day of storage and share lactobacillii: streptococcii third and sixth day of storage was 1:1.63 and 1:1.60. Ninth day of storage in all samples were more lactobacilii than streptococii. The differences in sensory scores between yoghurt samples from cow's, goat's and mixed milks were not significant.
Keywords
yoghurt from goat's and cow's milk; storing; quality, viscosity
Hrčak ID:
95010
URI
Publication date:
15.12.1996.
Visits: 1.634 *