Invited review: Role of Bacillus licheniformis in the dairy industry-Friends or foes?

Bacillus licheniformis is one of the major spore-forming bacteria with great genotypic diversity in raw milk, dairy ingredients, and final dairy products; it is found throughout the dairy-processing continuum. Although being widely used as a probiotic strain, this species also serves as a potential risk in the dairy industry based on its roles in foodborne illness and dairy spoilage. Biofilm formation of B. licheniformis, combined with the heat resistance of its spores, make it impossible to prevent the presence of B. licheniformis in final dairy products by using traditional cleaning and disinfection procedures. Despite the extensive efforts to identify B. licheniformis in various dairy samples, no reviews have been written on both hazards and benefits of this sporeformer. This review discusses the prevalence of B. licheniformis from raw milk to commercial dairy products, biofilm formation and spoilage potential of B. licheniformis, and possible prevention methods. In addition, the potential benefits of B. licheniformis in the dairy industry are also summarized.