Determining the amount of endotoxin in packed and conventional boiled milk

Milk is a very complex food source. Probiotic bacteria, especially Lactobacillus, in its microflora have an important role in the regulation of intestinal flora and mucosal immunity. The main purpose of disinfection of milk is to eliminate the presence of contaminating bacteria without harming the probiotic bacteria. Although it is possible to kill bacteria in heat-treated food sources, they may contain bacterial degradation products. One of these products is lipid-A, which can cause endotoxic effects in humans. This study was carried out with the aim of investigating endotoxin levels in milk disinfected with UHT method and traditional methods. Milk was collected from delicatessens, markets and villages. Open raw milk samples were boiled and cooled and frozen at -20 °C. Packaged milk samples were studied as soon as the lid was opened. In the study, 40 packaged milk samples and 40 open milk samples collected from delicatessens and villages were taken. The samples were inoculated on blood agar and EMB agar and incubated for 20-24 hours at 36±1 °C. Identification of overgrown bacteria was done using conventional and biochemical methods. Endotoxin level; It was determined quantitatively by ELISA test. A total of 80 samples, 40 of which were marketed as packaged and 40 as open, were included in the study. Lactobacillus spp. Its reproduction has been detected. There was no statistically significant difference between the two groups in terms of Lactobacillus isolasyanu (p = 0.09). In 9 (22.5%) of the open milks, a bacterial contamination was detected in the packaged milks. There was a statistically significant difference between the two groups in terms of detection rates of contaminating bacteria (p<0.05). Endotoxin was detected at the rate of 9.5-35.48 pg/mL (mean 18.66±5.28) in packaged milk and 3.67-15.27 pg/mL (mean 9.34±2.45) in open milk. There was a statistically significant difference between the two groups in terms of mean endotoxin detection rates (p<0.05).