Spoilage by Alicyclobacillus Bacteria in Juice and Beverage Products: Chemical, Physical, and Combined Control Methods
Alicyclobacillus is a genus of spoilage bacteria causing contamination of juices and other beverage products that cannot easily be contaminated by other microbes because of their high acid contents. During the last 4 decades since the first species of Alicyclobacillus was isolated in 1967, Alicyclobacillus has become a major concern to the global juice and beverage industries, and many promising methods have been developed and applied to control them. After introducing the history and general characteristics of Alicyclobacillus, as well as their heat resistance and spoilage, this review focuses on the control methods against Alicyclobacillus, including chemical and physical methods and combined methods. All these control methods show inhibitory or killing effects against Alicyclobacillus to some extent and, moreover, some of them have been put to use in the juice and beverage industries for decades and shown to be quite effective, although further developments can be achieved and new methods are constantly being established and investigated. Although it is difficult to compare the effects with one another among these methods because of the different experimental conditions in different reports, some of them, such as the treatments of nisin and high hydrostatic pressure, are well studied and proved to have extensive application prospect. The inhibitory factors, test strains and media, and especially the detailed experimental conditions and main results of these control methods are summarized here. The limitations of some methods mainly relating to the changes of products’ sensory qualities are also presented.