Enumeration and Identity of Lactobacilli in Dietary Products1

Abstract

A medium was developed for selectively enumerating bile-resistant lactobacilli by adding 0.15% oxgall to lactobacillus selective agar (BBL). Lactobacilli were not found in many products sold as sources of Lactobacillus acidophilus, whereas others contained widely different numbers of lactobacilli capable of forming colonies on the bile medium. Of seven products from which lactobacilli were isolated, only three contained L. acidophilus. One of these products was from a pharmacy and the other two were from dairy processor(s).