PORK FAT HYDROLYZED BY STAPHYLOCOCCUS-XYLOSUS

Staphylococcus xylosus is used as a starter culture in the production of fermented sausages. Its ability to hydrolyse pork fat was investiga ted. Within 15 days of incubation an interaction of bacterial growth, lipase production and lipase activity in a pork fat containing medium caused liberation of fatty acids. The free fatty acids were determined both qualitatively and quantitatively. The effects of incubation temp erature and pH were studied using Response Surface Methodology. Within the area of interest for the production of fermented sausages, no loc al maximum or minimum liberation of fatty acids was found. A rise in p H increased the amount of free fatty acids. Below pH 5.0, the amount o f liberated fatty acids was insignificant although the viable count wa s > 10(6) cell/g emulsion. Of the two factors, pH was most influential in affecting the amount of free fatty acids. A rise in temperature on ly slightly increased the amount of free fatty acids and hydrolysis to ok place at all temperatures from 14 to 27-degrees-C. The strain liber ates the fatty acids in a nonspecific way, in about the same proportio ns as those in which they occur in the pork fat.