Microbiological spoilage and safety risks in non-beer beverages produced in a brewery environment

During the past ten years major changes have occurred in the global beverage market. Functional beverages and bottled waters constitute the fastest growing sectors. Energy drinks and non-alcoholic malt beverages are also gaining popularity. This literature review aims to provide state-of-the-art knowledge on microbial spoilage and safety risks in non-beer beverages with emphasis on functional and specialty products. Many modern beverages have higher level of nutrients for microbial growth, lower acidity and / or milder carbonation level compared to traditional soft drinks. Thermal and chemical preservation have also been reduced. These changes in the beverage production are expected to increase the spoilage rate unless the gap is filled with new antimicrobial hurdles. Yeasts and lactic acid bacteria will probably remain the major spoilage microbe types also in the modern products, but the range of species is expected to increase. Bacteria are likely to gain increasing importance in the spoilage. Emerging spoilers include e.g. alicyclobacilli, Asaia, clostridia, entero- and propionibacteria. Possible new microbial health risks may arise from the use of low-acid juice ingredients and increasing ingredient import. Pathogenic bacteria may not only survive but can also grow in the low-acid fruit and vegetable juices. Moreover, novel ingredients may improve the survival of pathogens in the beverages, or bring new harmful microbes or their metabolites into products. More research is needed about the occurrence and faith of pathogens and emerging spoilers in the modern non-beer beverages. Whenever new products are developed, it is important to go through every change in the recipe, packaging and processing in order to consider microbial risks. The future challenge is to produce microbiologically safe and stable beverages while maintaining maximum sensory and nutritional quality. Exploiting the synergistic effect of natural antimicrobials together with GRAS substances and mild physical preservation is a potential approach for controlling harmful microbes in beverages. Predictive microbiology can help in optimising the preservative systems and describing the behaviour of contaminants in complex non-beer beverages.