Nisin and its usage in breweries: a review and discussion

The most common source of microbiological contamination in today's brewing industry is Gram-positive bacteria. Therefore, different approaches are used in daily quality assurance routines in order to prevent and to eliminate infections. Normally, common disinfection agents are applied within the automated cleaning processes, but there is a growing market requirement for the reduction of their usage and a substitution with natural ingredients. Therefore, implementation of a natural bio-preservative such as nisin, a bacteriocin capable of eliminating up to 90% of Gram-positive beer spoilage bacteria, poses an effective, natural solution. This article summarizes bacteriocins currently used in food production. Subsequent specific details about nisin including its mode of action, characteristics, legal aspects, production methods, interferences and synergistic factors are presented. Additionally, a variety of analytical methods to determine nisin's concentration are included and possible industrial applications of nisin in the brewery environment are discussed. Copyright (C) 2015 The Institute of Brewing & Distilling