RAZLIKE U SADRŽAJU I SASTAVU MASTI U MIŠIĆNOM TKIVU PRSA I ZABATAKA KOD BROJLERSKIH PILIĆA ; DIFFERENCES IN FAT CONTENT AND FATTY ACID COMPOSITION OF BREAST AND THIGH MUSCLES IN BROILER CHICKENS

Cilj rada bio je utvrditi razlike u sastavu masnih kiselina masti mišićnog tkiva prsa i zabataka u pjetlića hibridne kombinacije ROSS 308. U 40. danu tova pjetlići su postigli prosječnu živu masu od 2.829 ± 0.299 g. Iz rezultata istraživanja proizlazi da mišićno tkivo zabataka sadrži statistički visoko značajno veću (P ≤ 0.01) količinu masti (82.64 g/kg) u usporedbi s mišićnim tkivom prsa (14.28 g/kg). Na temelju analiza utvrđeno je da postoje razlike i u kakvoći, tj. u sastavu masnih kiselina (FA). Ove su razlike visoko značajno veće (P ≤ 0.01) u udjelu nezasićenih (NeFA) masnih kiselina u mišićnom tkivu zabataka (64.59 ± 4.706 g/100 g masti), u usporedbi s mašću mišićnog tkiva prsa (54.09 ± 4.691 g/100 g masti). Mast mišićnog tkiva zabataka pokazala je statistički visoko značajno veći (P ≤ 0.01) udio mononezasićenih (MUFA) masnih kiselina (38.29 ± 4.757 g/100 g masti) i statistički značajno veći (P ≤ 0.05) udio polinezasićenih (PUFA) masnih kiselina (26.29 ± 2.580 g/100 g masti) u usporedbi s mišićnim tkivom prsa (30.90 ± 4.199 g/100 g masti i 23.192 ±2.304 g/100 g masti). Mast mišićnog tkiva zabataka sadržavala je i visoko značajno veći (P ≤ 0.01) udio n-6 FA (23.99 ± 2.331 g/100 g masti) i n-9 FA (38.29 ± 4.757 g/100 g masti), u usporedbi s mašću mišićnog tkiva prsa (20.92 ± 2.084 g/100 g masti i 30.90 ± 4.199 g/100 g masti). Kod n-3 FA nisu ustanovljene statistički značajne razlike između prosječnih vrijednosti mišićnog tkiva zabataka (2.30 ± 0.254 g/100 g masti) i mišićnog tkiva prsa (2.26 ± 0.263 g/100 g masti). Unatoč većem udjelu PUFA, u mišićnom tkivu zabataka pilića bio je hranidbeno povoljniji omjer n-3 FA:n-6 FA kod mišićnog tkiva prsa (1:9.25), u usporedbi s mišićnim tkivom zabataka (1:10.43). Iz rezultata istraživanja proizlazi da je, s gledišta prehrane ljudi, mišićno tkivo prsa dijetetski povoljnije od mišićnog tkiva zabataka ne samo zbog nižeg sadržaja ukupne mišićne masti već i zbog povoljnijeg omjera n-3 FA : n-6 FA. ; The main aim of this work was to determine the differences in fatty acid composition of breast and thigh muscles in male ROSS 308 hybrid combination chickens. The mean live weight of male chickens on day 40 of fattening was 2.829 ± 0.299 g. It follows from the results that fat content in thigh muscles of chickens (82.64 g per kg) was very significantly higher (P ≤ 0.01) than that in breast muscles (14.28 g per kg). Analyses also revealed the differences in fat quality i.e. fatty acid composition (FAs), between both types of muscles. For example, the unsaturated fatty acids content (UFAs) in thigh muscles (64.59 ± 4.706 g per 100 g of fat) was very significantly higher (P ≤ 0.01) than that in breast muscles (54.09 ± 4.691 g per 100 g of fat). Fat in thigh muscles contained a very significantly higher (P ≤ 0.01) level of monounsaturated fatty acids (MUFAs) (38.29 ± 4.757 g of per 100 g of fat) and a significantly higher (P ≤ 0.05) level of polyunsaturated fatty acids (PUFAs) (26.29 ± 2.580 g per 100 of fat), compared to breast muscles (30.90 ± 4.199 g per 100 g of fat and 23.192 ± 2.304 g per 100 g of fat, respectively). Fat in thigh muscles also contained very significantly higher levels (P ≤ 0.01) of n-6 FAs (23.99 ± 2.331 g per 100 g of fat) and n-9 FAs (38.29 ± 4.757 g per 100 g of fat) compared to fat in breast muscles (20.92 ± 2.084 g per 100 g of fat and 30.90 ± 4.199 g per 100 g of fat, respectively). No statistically significant differences were found between the mean levels of n-3 FAs in thigh (2.30 ± 0.254 g per 100 g of fat) and breast muscles (2.26 ± 0.263 g per 100 g of fat). Although the PUFAs content in thigh muscles was higher, the n-3 FAs/n-6 FAs ratio in breast muscles (1:9.25) was more favourable from a dietetic point of view than that in thigh muscles (1:10.43). It follows from the results that breast muscles characterized by the lower amount of muscle fat and a more favourable n-3 FAs/n-6 FAs ratio are dietetically more suitable for human nutrition than thigh muscles.