Microbiological contamination of hen's eggshell in different housing systems

Kokošje jaje pripada osnovnoj namirnici u prehrani ljudi i iznimno je bogato hranjivim tvarima, no jednako tako može biti izvorom raznih mikroorganizama te uzrok otrovanja ljudi. Zato je bitno brinuti o procesu proizvodnje jaja, od nesenja pa sve do njihove distribucije i prodaje. Cilj rada bio je istražiti i usporediti mikrobiološku kvalitetu ljuske konzumnih jaja koja se nalaze u prodaji na našem tržištu te opisati načine uzgoja. Analizirana jaja bila su porijeklom iz kaveznog (konvencionalan) te slobodnog i podnog (alternativni) uzgoja. Za mikrobiološku pretragu ljuske pripremljeni su ispirci ljusaka jaja koji su pretraženi na ukupni broj aerobnih mezofilnih bakterija, prisutnost enterokoka i bakterije Escherichia coli. Bez obzira na način uzgoja nesilica, broj aerobnih mezofilnih bakterija nije pokazivao velika odstupanja i bio na razini od 3,5 do 3,9 log10. Broj enterokoka prosječno je iznosio 2,8 log10 CFU/ml na ljusci jaja iz slobodnog, 2,3 log10 CFU/ml iz podnog te 1,1 log10 CFU/ml iz kaveznog uzgoja. Bakterija E. coli je utvrđena u broju manjem od 10 CFU/ml isprika.Hen's egg belongs to basic foodstuffs in human nutrition and it is extremely rich in nutrients, but also can be the source of various microorganisms and the cause of human poisoning. That is why it is important to worry about the process of egg production from laying to distribution and selling. The aim of this study was to investigate and compare the microbiological quality of the egshells that are sold on our market and to describe housing systems. The analyzed eggs are originated from battery cages (conventional), free range and deep litter housing systems (alternative). Eggshell's lavages were prepared for the microbiological examination of the eggshell and were searched for the total number of aerobic mesophilic bacteria, the presence of enterococci and bacteria Escherichia coli. Regardless of the housing system, the number of the aerobic mesophilic bacteria did not show large deviations and was at the level 3,5 to 3,9 log10. The average number of enterococci was 2,8 log10 CFU/ml on egshell from free range, 2,3 log10 CFU/ml from deep litter and 1,1 log10 CFU/ml from battery cage. E. coli was found to be below 10 CFU/ml of lavage