In vitro resistance of enterococcus faecium and lactobacillus helveticus against stress conditions, sodium chloride and curing salts: preliminary study aimed application as starter culture in fermented sausage

Abstract

The objective of this study was to evaluate the Enterococcus faecium (ATCC 8459) and Lactobacillus helveticus (ATCC 15009) in vitro resistance against stress conditions (acidity and bile salts); curing salts (sodium nitrate and nitrite) and sodium chloride, aiming application as starter culture in fermented sausage. Acid resistance test was carried out at pH values (3, 4 and 5) and bile salts (0, 0.15 and 0.30%), both monitored at times 0 and 4 hours. For resistance to curing salts was used concentration of 0.1% and sodium chloride concentrations tested were 1.0, 2.0 and 3.0%. Enterococcus faecium and Lactobacillus helveticus were resistant to bile salts; however, E. faecium was more sensitive to acidity. In presence of sodium chloride and curing salts, Lactobacillus helveticus showed the highest sensitivity. Both microorganisms had satisfactory results for this test, indicating that they may be used as starter culture in the preparation of meat products, such as fermented sausages. Moreover, these products composition may affect positively the starter culture viability in final product.