Microbiological Safety and Functional Properties of a Fermented Nut-Based Product

Area of Science:

• Food Science
• Microbiology
• Fermentation Technology

Background:

• Plant-based fermented foods are gaining traction as alternatives to animal products.
• Lactic Acid Bacteria (LAB) are crucial for fermenting nut-based products, enhancing safety and shelf-life.
• Developing vegan products with desirable sensory and functional attributes requires controlled fermentation.

Purpose of the Study:

• To investigate the efficacy of specific LAB consortia in producing a safe, cheese-like fermented plant-based product.
• To evaluate the antimicrobial activity of LAB against key foodborne pathogens.
• To characterize the impact of LAB fermentation on the aroma profile and phenolic compounds of the nut-based product.

Main Methods:

• LAB strains were isolated and combined into starter cultures for nut fermentation.
• Challenge tests were performed using inoculated nuts against Listeria monocytogenes, Escherichia coli, and Salmonella Enteritidis.
• Pilot-scale production was conducted, followed by characterization of aroma compounds and phenolic content.

Main Results:

• A consortium of Lactiplantibacillus plantarum 82 and Leuc. carnosum 4010 achieved rapid acidification (pH < 4.4 in 18h) and reduced pathogen loads.
• Listeria monocytogenes was eliminated within seven days; E. coli and Salmonella Enteritidis counts were significantly lower.
• Fermentation enhanced cheese-like aroma compounds (acetoin, diacetyl) and increased beneficial phenolic compounds.

Conclusions:

• A guided fermentation process using a specific LAB consortium can ensure the safety of a cheese-like vegan product.
• This fermentation strategy improves the aromatic profile and functional properties, including antimicrobial compounds.
• The study successfully established a method for creating a safe, palatable, and functional fermented plant-based food.