Antimicrobial Activity of Methanolic Extract from Clove and the Test of Preservative Power of Ras Cheese

Abstract

The effect of methanolic extract from Clove (Syzygium aromaticum L.) and sodium sorbate (SS) on growth of certain fungal, bacteria strains and Ras cheese sampls during storage were examined. Ras cheese made from standardized cow's milk (4% fat) with a modified process. During production curd cheese, four groups were formed: first group taken after salting for 12 days, without Clove extract (CE), as control, second group (T1) add CE to curd cheese, third group (T2) add SS to curd cheese, and fourth group (T3) add CE on surfaces of each cheese wheel. After completely salting process, the cheese ripened at 15±2ºC and about 85% relative humidity for 3 months. All treatments evaluated microbiologically at fresh, and after one, two & three months. The samples we took from the exterior (Ex) and inside (In) of cheese wheel. The control samples had higher counts of yeast & fungal and TBC in S and M of cheese than that of other treatments. The counts of yeast & fungal and TBC of S and M of control samples increase with increasing of storage, while cheese treated with CE & SS decrease with increasing storage periods up to end of storage. Moreover, the coliform bacteria were not detected up to the end ripening. Generally, the results showed that the SS had higher antimicrobial effect than that with CE on growth of yeast & fungal and general microorganism especially the responsible for ripening cheese during storage.