Résumé:
This work consists in following the antimicrobial effect of the aqueous extract of a medicinal
plant Rosmarinus officinalis L (Rosemary) cultivated in the region of Naama (Algeria) vis-à-vis
the germs responsible for spoilage of sheep meat. Ouled Djellel breed from steppe pastures in
Bogtob wilaya of El Bayadh during nine (09) days of cold storage at 4 ° C. The extraction of the
main active compounds of the plant was carried out by macerating the plant in water. The
rosemary extract obtained after evaporating the solvent was diluted to 0, 20, 40, 60, 80, and
100%, respectively. Eighteen (18) samples of 300 g of meat each were taken aseptically from
animal carcasses after 18 hours of soaking. Batches of 3 pieces of meat were then made up and
stored individually in polystyrene trays. Each batch was treated on the first day with one of the
extract concentrations prepared as before at a rate of 6 ml. The microbiological analyzes carried
out on the experimental meat samples concerned: total aerobic mesophilic flora, Staphylococcus
aureus, Pseudomonas, psychrotrophic flora and thermotolerant coliforms.
The level of contamination by spoilage germs (total aerobic mesophilic flora, Staphylococcus
aureus, Pseudomonas, psychrotrophic flora and thermotolerant coliforms) seems to decrease
remarkably (p <0.01) during the 09 days of cold storage in the meat of leg of lambs. treated in
particular with pure aqueous extract and diluted to 80% compared to that of the control, not
having undergone the addition of any additive as a preservative.
The aqueous extract of the studied plant species Rosmarinus officinalis L. can undoubtedly be
an effective substitute for chemical additives such as nitrates and nitrites harmful to health often
used in cold cuts and processed meats. Being rich in phenolic compounds, this extract has shown
a real antimicrobial power vis-à-vis some germs responsible for food poisoning capable as a
consequence of appreciably extending the shelf life of meats at 4 ° C.
