Spoilage yeasts: What are the sources of contamination of foods and beverages?

Send to Int J Food Microbiol. 2018 Jul 25;286:98-110. doi: 10.1016/j.ijfoodmicro.2018.07.031. [Epub ahead of print] Hernández A1, Pérez-Nevado F2, Ruiz-Moyano S2, Serradilla MJ3, Villalobos MC2, Martín A2, Córdoba MG2. Author information 1 Nutrición y Bromatología, Escuela de Ingenierías Agrarias, Instituto Universitario de Recursos Agrarios (INURA), Universidad de Extremadura, Ctra. de Cáceres s/n, 06007 Badajoz, Spain. Electronic address: ahernandez@unex.es. 2 Nutrición y Bromatología, Escuela de Ingenierías Agrarias, Instituto Universitario de Recursos Agrarios (INURA), Universidad de Extremadura, Ctra. de Cáceres s/n, 06007 Badajoz, Spain. 3 Área de Vegetales, Centro de Investigaciones Científicas y Tecnológicas de Extremadura (CICYTEX), A5 km 372, 06187 Guadajira, Spain. Abstract Foods and beverages are nutrient-rich ecosystems in which most microorganisms are able to grow. Moreover, several factors, such as physicochemical characteristics, storage temperature, culinary practices, and application of technologies for storage, also define the microbial population of foods and beverages. The yeast population has been well-characterised in fresh and processed fruit and vegetables, dairy products, dry-cured meat products, and beverages, among others. Some species are agents of alteration in different foods and beverages. Since the most comprehensive studies of spoilage yeasts have been performed in the winemaking process, hence, these studies form the thread of the discussion in this review. The natural yeast populations in raw ingredients and environmental contamination in the manufacturing facilities are the main modes by which food contamination occurs. After contamination, yeasts play a significant role in food and beverage spoilage, particularly in the alteration of fermented foods. Several mechanisms contribute to spoilage by yeasts, such as the production of lytic enzymes (lipases, proteases, and cellulases) and gas, utilisation of organic acids, discolouration, and off-flavours. This review addresses the role of yeasts in foods and beverages degradation by considering the modes of contamination and colonisation by yeasts, the yeast population diversity, mechanisms involved, and the analytical techniques for their identification, primarily molecular methods. KEYWORDS: Food and beverage; Identification and typing reaction methods; Molecular biology-based procedures; Sources of contamination; Spoilage yeasts PMID: 30056262 DOI: 10.1016/j.ijfoodmicro.2018.07.031 Share on FacebookShare on TwitterShare on Google+