VZTAH KONCENTRACE ZDRAVOTNĚ VÝZNAMNÝCH SKUPIN MASTNÝCH KYSELIN KE SLOŽKÁM A TECHNOLOGICKÝM VLASTNOSTEM KRAVSKÉHO MLÉKA

Abstract

Groups of fatty acids (FAs) in milk fat can have positive and negative impact on consumer health. Profile of FAs could be influenced by dairy cow nutrition, breed, milk yield level et cetera. The question is what relationships the FAs could have to quality of milk products? Relationships between FAs and their groups to selected milk indicators were studied in Czech Fleckvieh and Holstein cows (64 bulk milk samples). There were 8 herds in 2-year investigation during winter and summer season. The relationship of saturated FAs (SAFA; 66.22%) was significant only to lactose (L) content (0.290; P < 0.05). The relationships of monounsaturated FAs (MUFA; 29.21%) to milk indicators (MIs) were in­si­gni­fi­cant (P > 0.05). The relationships of polyunsaturated FAs (PUFA, beneficial for consumer health; 4.53%) to MIs were narrower: fat (T, 0.321; P < 0.05); lactose (L, 0.458; P < 0.01); milk alcohol stability (AL, 0.447; P < 0.01); titration acidity (SH, 0.342; P < 0.01); cheese curd quality (KV, 0.427; P < 0.01); milk fermentationability (JSH, 0.529; P < 0.001), streptococci count in yoghurt (Strepto, 0.316; P < 0.05); total count of noble bacteria in yoghurt (CPMUK, 0.314; P < 0.05); streptococci/lactobacilly ratio (StreptoLacto, 0.356; P < 0.01). The relationships of conjugated linoleic acid (CLA; markedly beneficial for health; 0.68%) to MIs were: T (0.379; P < 0.01); L (–0.542; P < 0.001); AL (0.266; P < 0.05); KV (0.411; P < 0.01); Strepto (0.260; P < 0.05); StreptoLacto (0.270; P < 0.05). The higher CLA levels were connected in this way with: higher fat content; lower lactose content; lower alcohol stability; lower streptococci count in yoghurt; lower streptococci/lactobacilly ratio in yoghurt. The PUFA and CLA representation decreased with L increase. Simultaneously some technological milk properties such as alcohol sta­bi­li­ty and fermentationability were slightly improved.