Hanan Kurabi *⁽¹⁾

(1). Food Science Department, Faculty of Agriculture, University of Aleppo, Syria. (*Corresponding author: Dr Hanan Kurabi. E-Mail: hanansrn76@gmail.com , Tel:0988944300)

Received:20/10/2024                  Accepted: 9/2/2025

Abstract: 

The research aimed to compare the microbial quality of raw cow’s milk treated with pasteurization and treated with ozone, and to evaluate the effect of different ozone doses on some physical and chemical properties of sterilized skimmed milk samples inoculated with some pathogenic bacteria, in addition to compare the effect of ozone on Gram-negative and Gram-positive bacteria. The research was carried out in the microbiology  laboratory in the Department of Food Sciences at the Faculty of Agricultural Engineering at the University of Aleppo during the period from February to June 2024.The results showed a clear decrease in the initial microbial load of milk, whether in milk samples thermally treated with pasteurization or treated with ozone, it was found that treating milk with ozone for 5 minutes at a rate of 400 mg O3/hour had no effect on the microbial quality, while treating raw milk with ozone for 25 minutes at a rate of 400 mg/O3 hour led to ten-tenth reductions in the natural milk flora. All of this had a positive effect on milk quality and increased shelf life. No significant changes were observed in the physical and chemical properties. Gram-negative bacteria was more affected by ozone treatment than gram-positive bacteria.

Keywords: milk, ozone, pathogenic bacteria, microbial quality.

Full paper in Arabic: PDF