Prunus mahaleb fruit fermentation for new functional foods and beverages

Objective: Prunus mahaleb (P. mahaleb) is a deciduous tree native to Mediterranean region, resistant to dry climate and several diseases. P. mahaleb fruits are small, highly pigmented drupes representing a new source of bioactive compounds, above all anthocyanins. Since its astringent and sour taste, it is not considered not-edible. This study aimed to improve sensory characteristics of P. mahaleb fruits after fermentation with different Saccharomyces cerevisiae and Lactobacillus plantarum strains. Methods: Four different bacterial and one yeast strains, as single or mixed starter formulation, were used to inoculated an aqueous suspension of intact fruits. Microbial growth kinetics have been described during 20 days of fermentation. The fermented fruits and fermentation broth were chemically characterized by HPLC analysis and their organoleptic properties assessed by hedonic panel. Results: The obtained results indicated that all the employed strains were able to grow and to ferment the matrix. However, the mixed starter FG69+Li180-7 (L. plantarum/S. cerevisiae) had the best impact on sensory characteristics of fruit and fermented medium. As concerning probiotic potential of L. plantarum strains utilized, they all have been able to survive to simulated gastric and pancreatic digestion. However, the only strain able to further resist to bile salts was the L. plantarum FG68. Conclusions: The obtained results allowed us to conclude that sourness of P. mahaleb fruits is strongly reduced by fermentation with a new starter co-culture made up with L. plantarum and S. cerevisiae, thus obtaining a new functional and probiotic foods and beverages.