TECHNOLOGICAL EFFECTS ON THE SURVIVAL OF CAMPYLOBACTER-JEJUNI IN FOODS OF ANIMAL ORIGIN

The effects of some technologies (cooling, freezing, salting, packaging, fermentation, cold smoking, heat treatment) on the survival of Campylobacter jejuni were investigated. The different technological procedures can be considered as barriers influencing to a certain degree the survival of C. jejuni. The low value a(w) on the surface of chilled meat and oxygen presence reduce the occurrence of C. jejuni, but the low storage temperature prolongs the survival of C. jejuni to two days. In chilled poultry the high relative water content is combined with the low temperature and C. jejuni is able to survive even for five days. In the freezing process the low temperature has only partial effects on C. jejuni devitalization; C. jejuni can survive in this case for two to eight weeks. The survival of C. jejuni is prolonged considerably by packaging: six to seven days in polyethylene sheet, 10 days in vacuum packing and 10 to 13 days in gas packing (80 % N2 and 20 % CO2). NaC1 can partly devitalize C. jejuni, and in comminuted meant it survives for five to seven days. In the non-precooked meat products (TNMV) and with the minimally fortnight time of ripening a number of barriers play their role which are destroying C. jejuni (a(w), H, antagonistic microflora). Due to these barriers C. jejuni was isolated in these products maximally for seven days. In this type of products with short durability (two to three days) the action of barriers is limited, that means C. jejuni could be demonstrated for two to six days. In the process of lactic fermentation, C. jejuni is influenced largely by the low pH values and antagonistic effects of microflora. The temperature above 60-degrees-C acting for a minute eliminates perfectly C. jejuni from foods. The efficiency of different technological procedures with respect to C. jejuni devitalization is not high enough in many cases because the germ counts are reduced only partially. The only exceptions are heat treatment at the temperature of 60-degrees-C and the non-precooked meat products (TNMV) with long time of ripening (minimally a fortnight).