Differences in physico-chemical parameters of goat milk depending on breed type, physiological and environmental factors

2020 Turk veterinerlik ve hayvancilik dergisi  
3 The objective of the research was to analyse the technological parameters of 4 milk and assess the impact of selected factors, i.e. the genetic group of goats (improved 5 goats -Saanen crosses vs various crossbreds of unknown genetic originbreedless 6 goats with different coat for which no breeding books were kept), production season 7 (winter, spring/summer and autumn), which was associated with the stage of lactation 8 (1, 2 and 3), the region where the goats were raised (upland or
more » ... (upland or mountainous areas) and 9 daily yield (< 1.0, 1.0 -2.0 or > 2.0 kg). A total of 480 milk samples were evaluated 10 (203 milk samples from Saanen crosses and 277 from various crossbreds of unknown 11 genetic origin). The milk was tested for proximate chemical composition, casein 12 content, active and potential acidity, coagulation time and heat stability. All factors 13 analysed were found to significantly affect daily milk yield, potential acidity and 14 composition (contents of fat, non-fat dry matter, total protein and casein). Goat 15 crossbreds of unknown genetic origin produced milk with better chemical composition, 16 i.e. higher contents of fat, non-fat dry matter, total protein and casein, and technological 17 parametershigher heat stability (despite lower daily yield) than Saanen crosses, 18 especially in autumn (end of lactation). The region of production was also significant. 19 Goats raised in mountainous areas produced milk with a more favourable chemical 20 composition, i.e. higher content of dry matter and protein, including casein, but with 21 lower heat stability, in most cases irrespective of the production season. As daily milk 22 yield increased, there was a decrease in the content of fat and non-fat dry matter, 23 including total protein and casein, as well as a reduction in the rennet clotting time. 24 2 Analysed factors and their interactions play an important role in shaping the chemical 1 composition of goat milk and determines its technological usefulness. 2 3
doi:10.3906/vet-1912-102 fatcat:2xhj4qdqnvcrflnq5h4lkywq2m