Evaluation de la qualité microbiologique du lait pasteurisé et stérilisé commercialisé dans la région de -Ain- Temouchent

Abstract

Milk is a staple food in the daily diet due to its richness in essential nutrients such as calcium, proteins, and vitamins. However, this nutritional richness also makes it a favorable medium for the proliferation of microorganisms, rendering it highly susceptible to spoilage in the absence of proper storage conditions. Given the high level of milk consumption in Algeria, monitoring its microbiological quality is of critical importance for public health. This study was conducted within this context, aiming to evaluate the microbiological quality of pasteurized and sterilized (UHT) milk marketed in the Ain Témouchent region. Microbiological analyses were carried out on samples randomly collected from various points of sale, in accordance with the criteria defined in the Official Journal of the Algerian Republic (JORA No. 39, 2017). The tests targeted total mesophilic aerobic flora, Enterobacteriaceae, yeasts and molds, spore-forming bacteria, and other spoilage organisms. The results revealed that sterilized milk maintained satisfactory microbiological stability throughout the storage period, even at 32°C. In contrast, pasteurized milk showed an increase in microbial load starting from the second day, sometimes exceeding regulatory limits—indicating inadequate control of storage or refrigeration conditions. This study highlights the superior microbiological stability of sterilized milk compared to pasteurized milk. It also emphasizes the importance of strictly adhering to hygiene practices and cold chain requirements to ensure the safety and quality of milk intended for consumption.