EFFECT OF SAMPLING, RECONTAMINATION AND TEMPERATURE ON MICROBIAL QUALITY OF PASTEURIZED MILK

Seven different sampling valves were used to collect pasteurized milk recontaminated at different levels with Pseudomonas fluorescens. Statistical analysis showed no effect of the type of sampling valve on the total count of freshly pasteurized re-contaminated milk or on the count of cold-stored samples. The post-pasteurization contamination level was the most critical factor determining keeping quality at 6 or 10 degrees C. The results also showed that the sample volume and the sample storage container (sterile glass bottle, blood bag) influence the plate count of cold-stored samples.