Development of biopreservation strategies based on vegetables, fungi and starters to improve food safety in baked foods

Bread is a highly perishable product and, from a microbiological point of view, bacteria, yeasts and especially molds can potentially compromise its shelf life and hygiene safety. The growth of spoilage microorganisms makes foods no longer marketable and edible, causing hygienic-sanitary problems (presence of mycotoxins and allergenic substances), a decrease in nutritional value and generating huge economic losses. Due to the safety problems related to the extensive use of common preservatives in foods, as well as the onset of resistance by spoilage molds, restrictions to their use have been recently established at European level. Biopreservation strategies are therefore being tested, which include the use of ingredients of natural origin or compounds synthesized by microorganisms.
The research team has already been involved in research of edible antifungal matrices and compounds among waste from the agri-food industry (e.g. milling by-products, brewers’ spent grain), vegetable (hops, legumes) and fungal-derived substrates (e.g. from Trametes versicolor). Moreover, the team explored the possibility of using starters selected for their ability to synthesize compounds with antifungal activity, identifying promising strains of lactic acid bacteria and food-grade yeasts.
The need to identify new biopreservation strategies for industrial scale applications is currently one of the major requirements of the manufacturing sector.

The project aim is the set-up of innovative biopreservation strategies based on the use of vegetable/fungal substrates and starters selected for their antimicrobial activity as alternative to conventional preservatives (ethanol, propionates, sorbates).
The use of selected substrates and starters will also be aimed at improving the nutritional profile of the products (biological value/ digestibility of the protein fraction, increase in fiber content and antioxidant compounds, lowering glycemic index).
Research activities will be:

• Selection of antimicrobial vegetable and fungal matrices. 
• Selection of antimicrobial lactic acid bacteria and yeasts.
• Evaluation of the microbiological shelf-life of leavened baked good.
• Optimization of combined use of vegetable/fungal matrices and starters associations. 
• Characterization of the inhibition mechanisms and fungal response by omics techniques (IMPROVE_Crestoni_UNIROMA1).
• Characterization of the functional/nutritional profile of substrates and experimental products.

• Identification of novel and edible plant- and fungal-derived matrices able to inhibit the growth of spoilage molds in baked goods.
• Selection of food-grade starters (lactic acid bacteria and yeasts) to be used as starters for breadmaking, able to synthesize antimicrobial compounds during processing.
• Identification of the antifungal compounds and characterization of the inhibitory activity (spectrum, mechanisms, fungal response).
• Set-up of biotechnological protocols for obtaining antifungal substrates to be used as ingredients.
• Set-up of biotechnological protocols for the production of baked goods characterized by long microbial shelf-life (20-30 gg) and improved nutritional/functional profile (high protein digestibility, high fiber content and antioxidant activity, low glycemic index).