Zdzisław Zakęś, Barbara Jankowska, Tomasz Żmijewski, Mirosław Szczepkowski
Zdzisław Zakęś1, Barbara Jankowska2, Tomasz Żmijewski2, Mirosław Szczepkowski3
1Zakład Akwakultury, Instytut Rybactwa Śródlądowego w Olsztynie
2Katedra Technologii i Chemii Mięsa, Wydział Nauki o Żywności, Uniwersytet Warmińsko-Mazurski w Olsztynie
3Doświadczalny Ośrodek Zarybieniowy Dgał, Instytut Rybactwa Śródlądowego w Olsztynie
ABSTRACT. The aim of the study was to determine the slaughter yield and the proximate composition of the meat of perch reared in recirculation systems on commercial feed and of wild specimens of a similar body weight (about 120 g) caught in natural basins. The fish from the two groups did not differ in biometric characters such as body weight, total length (Lt) or body length (Lc), or in condition coefficient (P > 0.01). The gutted perch yield was 5% lower in reared individuals in comparison with wild individuals (93.7 vs. 87.9%) (P Ł 0.01). A similar relation was noted with regard to headed and gutted fish, and fillets with skin, and skinned fillets (P < 0.01). Reared perch had higher viscerasomatic (VSI), hepatosomatic (his), and intraperitoneal fat (IPF) index values (P Ł 0.01). The difference in the contents of all the primary ingredients (water, protein, fat, ash) differed significantly (P < 0.01) between the meat of wild and farmed perch The meat of the farmed perch contained more protein (20.1 vs. 17.6%) and fat (1.3 vs. 0.3%). Consequently, the calorie content of the wild and reared perch differed at 434.1 and 533.1 kJ/100 g fillet, respectively.
Keywords: perch, feeding, slaughter yield, proximate body composition
Przyjęto po recenzji 28.07.2008 r.