Antifungal lactic acid bacteria combinations as biopreservation tool in cheese production
Résumé
Spoilage is a major issue for the food industry, leading to important food waste and economic losses. Dairy
products, despite their microbial stability, are susceptible to acid-tolerant fungal contaminants. In this
context, antifungal cultures are of growing interest as an alternative to chemical preservatives or as a
complement tool to hurdle technologies. To develop antifungal cultures for the biopreservation of dairy
products, experiments were conducted in vitro and in situ. Firstly, an antifungal activity screening was
performed in cheese-mimicking and yogurt models. Thirty two lactic and propionic acid bacterial strains were
studied alone and then in combination for 5 strains of interest. This allowed selecting two binary
combinations as potential antifungal cultures. The selected combinations were then tested as adjunct
cultures in semi-hard cheeses produced at a pilot scale, to evaluate their antifungal activity and their impact
on cheese organoleptic properties, and compared with a commercial antifungal culture. Challenge and
durability tests confirmed the antifungal activity of the 2 selected combinations. All the cheeses showed
acceptable sensory properties, even if the ones with antifungal cultures, including the one with a commercial
culture, were characterized by a more marked flavour compared to the control ones (p<0.2). This work
followed an approach for the selection of antifungal cultures that ended up in the selection of 2 combinations
that are potential natural antifungal alternatives for the cheese industry.
Format : Poster