摘要：Activation of the lactoperoxidase system during raw milk storage and its effect on the microbiological properties of milk investigated. Thus, milks were separated four parts. Milks that contained 12:8 mg/l and 24:16 mg/l SCN:H2O2 were kept at 30°C for 6 hours. The third and the last one without addition of SCN:H202 was kept at 4°C and 30°C for 6 hours, respectively. The last one used as a control. Changes of pH value, acidity and microbiological content were determined at 0, 3rd, and 6th hours of this period. Results indicated that total mesophile aerobic and psychrotrophs bacteria counts, mesophile and thermophilic lactic acid bacteria counts, enterobacter and yeast/mould count were all affected by activation of lactoperoxidase system (p<0.05). Cooling of milk also affected microbial content except total psychrotrophs aerobic bacteria. It was determined that increasing of SCN: H2O2 concentration increasing antimicrobial effect of lactoperoxidase system. It was founded that activation of lactoperoxidase system as effective as cooling and it was more effective than cooling on total mesophilic aerobic, psychrotrophs bacteria and enterobacter. Effect of cooling-treatment and activation of lactoperoxidase system on pH and acidity were found to be important, statistically at same level (p<0.05).
