Usporedba kvalitativnih svojstava jaja Pekinške patke i Cherry Valley patke iz sustava slobodnog uzgoja

The aim of this study was to compare physical, morphological and mechanical characteristics of eggs collected from two duck breeds (Pekin duck and Cherry Valley duck). A total sample of 120 eggs (60 eggs of each duck breed) was collected from one-year-old free range raised ducks. The Cherry Valley duck eggs were significantly heavier (94.23 vs. 71.91 g) than Pekin ducks (P<0.01), had larger dimensions and higher shape index (73.80 vs. 70.16). There was no statistical difference between egg specific gravity. According to egg components proportion, the Cherry Valley duck eggs had higher percentage of albumen, while the Peking duck eggs had higher percentages of yolk and shell. The Pekin duck eggs had significantly higher yolk to albumen ratio and Haugh unit value (P<0.01). The average force required to rupture Cherry Valley duck eggs in all three axes (50.32 N) was significantly higher (P<0.01) than average force required to rupture Pekin duck eggs (42.64 N). The highest egg rupture force at both duck breeds tested in this study was determined in loading along the X-front axis, while the least resistance to rupture force was determined along the Z-axis.Cilj ovog istraživanja bio je usporediti fizikalna, morfološka i mehanička svojstva jaja sakupljenih od dvije pasmine pataka (Pekinška patka i Cherry Valley patka). Uzorak od 120 jaja (60 jaja od svake pasmine) prikupljen je od pataka starih godinu dana. Jaja Cherry Valley patke bila su značajno teža (94,23 prema 71.,91 g) nego Pekinške patke (P<0.01), imale su veće dimenzije i veći indeks oblika (73,8 prema 70,16). Nije bilo statistički značajne razlike između specifične težine jaja. Shodno udjelu glavnih komponenata, jaja Cherry Valley patke su imala veći postotak bjelanjka, dok su jaja Pekinške patke imala veći postotak žumanjka i ljuske. Jaja Pekinške patke imala su značajno veći omjer žumanjka i bjelanjka i vrijednost Haugh jedinice (P<0.01). Prosječna sila potrebna za razbijanje jaja Cherry Valley patke u sve tri osi (50,32 N) bila je značajno veća (P