CONTROL OF YERSINIA-ENTEROCOLITICA IN RAW PORK AND PORK PRODUCTS BY GAMMA-IRRADIATION

gamma-Radiation response of Y. enterocolitica 5692 and 152 was studied at 0 degrees C and at -40 degrees C in phosphate buffer (pH 7.00) as well as in 10% raw meat/salami homogenate. The strains investigated di d not differ in their response and were found to be sensitive to gamma -radiation but exhibited a tailing phenomenon in the survival curve. T he D-10 in homogenate was 0.25 kGy at 0 degrees C. This response was n ot affected at -40 degrees C. Storage studies of packs, inoculated art ificially with heavy inoculum of Y. enterocolitica (10(6) cfu/g) showe d that while samples of salami and cooked ham could be decontaminated at doses of 4 and 3 kGy respectively; cells could not be eliminated fr om raw pork meat even at the higher dose of 6 kGy. The role of differe nt treatments given prior to irradiation for revival of Y. enterocolit ica after irradiation storage was also studied. The dose of 1 kGy at - 40 degrees C was efficient in eradicating low numbers (<10(3)) of natu rally occuring Y. enterocolitica from raw pork meat without any reviva l during storage at refrigeration temperature. (C) 1997 Elsevier Scien ce B.V.