Enhanced sensory, antioxidant, and non-toxic anti-diabetes beverage development via co-culture fermentation of Lactiplantibacillus plantarum and Saccharomyces boulardii in coffee cherry pulp extracts

Coffee cherry pulp (CC), a phenolic-rich by-product of coffee processing, is often discarded, raising sustainability concerns. This study investigated co-culture fermentation of extracted CC using Lactiplantibacillus plantarum TISTR 2070 and Saccharomyces boulardii CNCM I-745 to enhance its functional potential. Conditions optimized via Box–Behnken design (7.30 log CFU mL −1 LAB, 2.52 log CFU mL −1 yeast, 30 °C, and 26 h) led to increases of 19% in total phenolic content and 26% in DPPH activity. Potent inhibition of α-amylase and α-glucosidase ( IC 50 : 4.67 and 3.13 mg mL −1 , respectively) suggests efficacy against carbohydrate-hydrolyzing enzymes. Cytotoxicity tests confirmed safety up to 500 μg mL −1 in Vero cells. Ethanol content remained low (1.40% v /v ABV), aligning with the characteristics of low-alcohol fermented beverages, the beverage exhibited favorable sensory acceptability (7.5/9 from 50 panelists), This strategy enhances resource utilization, supports circular food systems, and advances the Sustainable Development Goals. • Novel co-culture fermentation of upcycles coffee cherry pulp into a functional beverage. • Optimized LAB–yeast synergy boosted phenolics by 19% and antioxidants by 26%. • Fermented extract strongly inhibits both α-amylase and α-glucosidase. • Non-toxic and sensory accepted, supporting future commercial development. • Promotes sustainable valorization of agro-waste via bioprocessing innovation.