Abstract:
In order to evaluate the quality of cow's milk considered a the most exploited in dairy
production for human consumption in the region of Ghardaïa, seven dairy and derived production
units were chosen to carry out sampling under experimental conditions Two samples per dairy, one
for raw mil k of collection and the other for pasteurized milk packaged in bag . The germs foreseen
by the Algerian national standard were researched, physico- chemical analyzes were carried out in
parallel.
The results obtained from the raw and pasteurized milk of sev en units showed different
levels of protein, fat and lactose from one raw milk to another and from one pasteurized milk to
another with a pH value slightly acid and a titratable acidity of the order of 16D ° for the majority
of the samples. Both types of m ilk were devoid of pathogenic germs with a major risk to consumer
health such as (Staphylococcus aureus, Clostridium perfringens ). The total aerobic mesophilic flora
rate was variable and significant for the majority of samples of raw milk; it was between 2.7.10
4
and 2.10
8
CFU / mL, of which only two meet the standards. In pasteurized milk this microbial load
was decreased after pasteurization, but it was exceeded the norm. Fecal coliforms, absent in the
majority (6/7) of pasteurized milks, were more numerous in the mixing milk taken under the usual
hygiene conditions of the farm and with a significant load ranging from 0,5.10
2
and 9.10
6
CFU /
mL. Faecal streptococci were absent in 0.1 mL for the majority of raw milk samples (5/7).