INCIDENCE OF SALMONELLAE AND COLIFORMS AND SURVIVAL OF SALMONELLA-TYPHIMURIUM IN SALADS

in this research the determination of the contaminative levels of Salm onella and coliform bacteria in various prepared salads as Tzatziki (T aratory), Melitzanosalata (aubergine puree salad), Rossiki (Russian sa lad), Tyrosalata (cheese salad) and Hungareza (Hungarian salad) and th e evaluation of Salmonella survival times inoculated in cheese salad a nd aubergine puree salad were studied. Eighty one samples were examine d from seven processing plants at Thessaloniki area a furthermore, 110 enviromental samples of the various surface were carried out. McConke y broth (MPN method) for the isolation of coliform bacteria and Rappap ort-Vassiliadis (RV) Enrichment broth far the Salmonella were used. Co liform bacteria were enumerated >10(3)/g and the percentage of contami nation were: Tzatziki 23.5 %, aubergine puree salad 25 %, Russian sala d 47 %, Cheese salad 100 % an Hungarian salad 28.5 %. Fecal coliforms were determined >10/g and the percentage of contamination were: Tzatzi ki 11.8 %, aubergine puree salad 43.8 %, Russian salad 30.2 %, cheese salad 85 % and Hungarian salad 28.6 %. Salmonellae were isolated only from one environmental sample (serotype S. enteritidis.) The data of t he survival of two defferent populations (2 x 10(3) and 2 x 10(5)/g) o f S. typhimurium in aubergine puree salad and cheese salad stored at 4 degrees C and 10 degrees C were shown that were reduced to non detect able levels with in 3 to 9 days from the inoculation. The average pH w as ranged from 4.5 to 4.2 in aubergine puree salad and 4.5 to 4.4 in c heese salad during experimentation. The research was showed that the f low production diagram demands improvements concerning with the hygien ic conditions of processing plants.