Quality characteristics of rye sourdough fermented with a mixed culture of probiotic lactic acid bacteria and yeast exhibiting potent antioxidant properties

This study aimed to develop probiotic-rich fermented foods by co-culturing lactic acid bacteria (LAB) and yeast strains isolated from traditional makgeolli, focusing on their probiotic and antioxidant activities. Three yeast strains—Saccharomyces cerevisiae TM15, Pichia kudriavzevii TM26, and Kluyveromyces marxianus TM39—were identified and assessed for their survival in simulated gastrointestinal conditions, bile salt hydrolase (BSH) activity, and pathogen coaggregation, confirming their potential as probiotic candidates. Safety evaluations indicated no harmful enzyme or biogenic amine production, supporting their safe use in food applications. Co-culture with the probiotic LAB Pediococcus pentosaceus OP91 in rye sourdough enhanced microbiological stability, antioxidant activity, and antimicrobial properties. Specifically, co-cultures with S. cerevisiae TM15 increased β-glucan content and DPPH scavenging activity while reducing pathogen counts, indicating the potential of these strains for health-promoting functional foods.