The Use of Neem (Azadirachta Indica) Seed Oil as an Antimicrobial Agent in Milk

Abstract

This study was undertaken to evaluate the effectiveness of neem seed oil as an antimicrobial agent on the microbial load of milk stored at 7oC and 300 C. Pasteurized milk samples (63 o C for 30 minutes) were treated by neem seed oil in concentration (0.25, 0.50, and 1.00 gm/l of milk) and inoculated with E. coli, Pseudomonas aeruginosa and Staphylococcus aureus. The samples were stored at 7oC for 36 hr, while at 300 C the samples were stored for 12hr, and microbial examination as well as titratable acidity were determined. The results indicated that the concentration of neem seed oil did not significantly (P>0.05) affect the count of E. coli and Staphylococcus aureus at 7oC, while the count of Pseudomonas aeruginosa was affected (P< 0.05). The count of Pseudomonas aeruginosa and Staphylococcus aureus were not significantly (P> 0.05) affected by the concentration of neem seed oil at 30oC, however, the count of E.coli was affected (P<0.05). The storage period significantly (P<0.001) affected the number of all tested bacteria at 7oC and 30oC, with the count decreasing with the advancement of storage period. The acidity of milk was not significantly (P> 0.05) affected by concentration of neem seed oil, while the storage period slightly affected the acidity of milk samples