Pasteurization and ultra-high temperature treatment can kill most microorganisms in milk. However, since some bacteria such as Bacillus subtilis can resist pasteurization and ultra-high temperature treatments, even the most stringent heat treatments used to eliminate pathogenic microorganisms in the dairy industry cannot completely inactivate all microorganisms. In addition, highly heat-resistant spores can survive ultra-high temperature processing, so sterilized milk may be contaminated, causing bacterial spoilage in milk and dairy products during storage. In this review, the harms of Bacillus subtilis and its spores, spoilage-causing enzymes and biofilm to sterilized milk and the control measures for them are summarized so as to provide strategies for the prevention and control of Bacillus subtilis in sterilized milk and the quality assurance of milk and dairy products.

Bacillus subtilis has a wide range of applications in the agriculture, industry, medicine and healthcare sectors due to its wide distribution and harmlessness to the environment. In recent years, Bacillus subtilis has been explored worldwide and applied as a new biological bacteriostatic agent, but the application of antibacterial substances secreted by it is still at a theoretical stage. This paper reviews the classification, mechanism of action, possible future applications and extraction optimization of antibacterial substances from Bacillus subtilis. The production of high-dose and high-purity bacteriostatic substances from Bacillus subtilis is an urgent problem to solved before the wide application of them in food preservation and sterilization technologies. This makes it necessary to find ways to improve the purity and yield of bacteriostatic substances. The review concludes with possible directions for future exploration of bacteriostatic substances.