Functional beverage production through lactic acid fermentation of black chokeberry (Aronia melanocarpa) juice

Abstract

The aim of the present study was to evaluate the microbiological, physicochemical, and nutritional features of black chokeberries juice fermented by a novel potentially probiotic strain (Lacticaseibacillus paracasei SP5) immobilized on delignified wheat bran (DWB) and orange peel for 2 days at 30 °C and for 28 days at 4oC. In general, application of immobilization led to elevated viabilities of L. paracasei SP5 (>8.8 log cfu/mL) in all studied periods of fermentation and subsequently ameliorated fermentative capacities. The application of orange peel as immobilization support led to better total phenolic content of the fermented juice after the 48 h fermentation (10.4 GAE g/L) and the 4th week of cold storage at 4 °C (13.9 GAE g/L), compared to the respective results obtained through the application of immobilized on delignified wheat bran and the unfermented juice. Higher antioxidant activity (AA) was recorded in the fermented juices by immobilized cells in all studied periods compared to the unfermented juice. Specifically, remarkable levels were obtained through the application of immobilized L. paracasei SP5 on orange peel (79.8 mmol Trolox/L at the 3rd week of cold storage), while the respective values were slightly lower when delignified wheat bran applied and much lower in the case of unfermented juice. Chokeberry juices fermented by both immobilized cells retained sufficient volatile compounds (alcohols, ketones, and esters) even after the 4th week of cold storage, in contrast to unfermented chokeberry juice.