The quality of table eggs in relation to the age of laying hens

Provedeno je istraživanje utjecaja dobi i temperature skladištenja na kvalitetu konzumnih jaja. Od obilježja kvalitete jaja istraženi su težina jaja, bjelanjka, žumanjka i ljuske (g), širina i dužina jaja (mm), indeks oblika, čvrstoća i debljina ljuske (mm), pH vrijednost žumanjka i bjelanjka te boja žumanjka. Istraživanje je provedeno na 360 jaja podrijetlom od hibrida Lohmann Brown. Starost nesilica bila je 25.tjedan (mlade) i 69.tjedan (stare). Kvaliteta jaja utvrđivala se kod tek snesenih, zatim nakon sedam i četrnaest dana skladištenja. Jaja nesilica različite dobi čuvana su na sobnoj (22°C) temperaturi i u hladnjaku (4°C). Mlađe nesilice nesu lakša, kraća i nešto uža jaja. Težina ljuske, bjelanjka i žumanjka manja je kod mlađih nesilica. Starije nesilice imaju mekšu, a mlađe tanju ljusku jajeta. Kod tek snesenih jaja svjetliji žumanjak imaju mlađe nesilice. Mlađe nesilice imaju veći pH bjelanjka i žumanjka. Temperatura čuvanja jaja statistički značajno (P<0,05) utječe na boju žumanjka, pH vrijednosti bjelanjka i žumanjka, kao i na težine ljuske i bjelanjka. Dužim skladištenjem jaja u odnosu na svježa jaja pogoršava se njihova kvaliteta pri čemu značajniji utjecaj ima temperatura u odnosu na dob nesilica.In this research, the influence of age and temperature on quality of layer eggs was observed. Parameters included were egg weight, albumen weight, yolk weight and shell weight (g), widht and lenght of eggs (mm), shape index, firmness and thikness of egg shell (mm), pH value of yolk and albumen and yolk color. Number of eggs used was 360, from Lohmann Brown laying hen hybrid. Age of hens were 25. Weeks (young) and 69. Weeks (old). Quality of eggs was determined in fresh eggs, 7 days and 14 days of keeping. Temperature of keeping was room temperature (22°C) and fridge temperature (4°C). Young layers lay lighter, shorter and narrow eggs. Shell weight, albumen and yolk weight is lower in younger layers. Older layer have softer, and younger have thinner egg shell. In fresh eggs yolk is lighter in younger layers. Also they have higher pH of albumen and yolk. Temperature of keeping statisticaly significant (P