OCCURRENCE AND CONTROL OF LISTERIA SPP. I N READY-COOKED MEALS PREPARED WITH CHICKEN MEAT

This paper presents information, bibliography and scientific results a bout the prevalence of Listeria spp. in raw meat as well as in ready-c ooked meals; i.e. in portioned fried and roasted chicken meat in piece s, in minced meat and in swabs taken from work-benches, respectively. Methods are also described for the separation and determination of Lis teria spp., including pre-enrichment in UVM1 broth, post-enrichment in UVM2 broth, separation by means of the Listeria PALCAM agar (''Biolif e'' method) and determination with the aid of the API Listeria system. The number of the positive findings (27.8% in raw materials, 39.4% in swabs, 21.1% in ready cooked meals or 26.2% in the total number of sa mples (n=381) of various materials) refers to the fact, that the above mentioned methods proved to be effective and efficient. The following Listeria spp. bacteria were determined in the examined samples: L. mo nocytogenes (35%), L. innocua (16%), L. welschimeri and L. gray (12%). The level of the detected contamination clearly demonstrates the need to include Listeria spp., due to their importance for human health, i n the monitoring program of veterinary-hygienic inspection in the Repu blic of Croatia.