Natural Antifungal systems for prevention of mould spoilage in bakery products

Growth of spoilage fungi in intermediate moisture bakery products, specifically bread and cakes, is prevented by the addition of food-grade preservatives such as propionic, sorbic and benzoic acid. However, both legislative and consumer pressure exists to reduce these concentrations (EC Council Directive 95/2/EC). Sub-optimal concentrations can result in stimulation of both growth and mycotoxin production by spoilage yeast and filamentous fungi which cam significantly reduce shelf-life of bread and cakes, influence microbiological safety, and thus have important implication for both processing industries and consumers. There is a need to understand the impact of sub-optimal concentrations of preservatives in current use on spoilage moulds and shelf life length and then to specifically examine new natural/novel food-grade preservatives such as essential oils, anti-oxidants and bacteriocins as alternatives. Multi-target hurdle technology approaches will be used to examine the effect of individual and groups of factors (existing and novel preservatives, water activity, pH temperature and gas composition) and their interactions on germination and growth of spoilage yeast and filamentous moulds and where applicable on toxin production. The data will be used in the development of three-dimensional predictive models for determining mould-free shelf life periods, and to subsequently evaluate the feasibility of the integration of natural alternative preservatives into bakery products to conserve or increase shelf-life quality in bakery products processing systems.