Formulation of peptides rich fermented dairy beverage with multiple targets against diabetes using a proteolytic Lacticaseibacillus rhamnosus NCDC 24

Globally, more than one in 10 adults is now living with diabetes. There is a growing list of countries where one in five or even more adults have diabetes. Milk derived peptides have been reported to exert antidiabetic properties. The current study was designed to develop a fermented dairy beverage rich in peptides with Dipeptidyl peptidase-IV and α-glucosidase inhibitory and antioxidant properties using a single proteolytic culture Lacticaseibacillus rhamnosus NCDC 24, which could normalize the blood glucose levels in diabetic individuals. Six beverage formulations were prepared using combinations of skim milk and milk proteins and fermented with L. rhamnosus NCDC 24. Formulations were analysed for physicochemical, microbiological, sensorial and biofunctional properties. Nutrient mix supplementation was found to positively impact the growth and proteolytic activity of the culture and Formula 3 was observed to display maximum peptide content and bioactivities after 48 h of fermentation. However, all the beverages were sensorially acceptable only up to 24 h of fermentation beyond which hedonic score fell below 7.0 due to low pH and high acidity at extended fermentations. Further, effect of inoculum concentrations on bioactivities of formula 3 was investigated. At 1x107 CFU/mL inoculum level, beverage exhibited elevated peptide content (0.745±0.06 mg/mL Leucine equivalent), DPP-IV (44.1±2%) and α-glucosidase inhibitory (36.68±2.4%) and ABTS (685.9±15.8 μM/L Trolox equivalent) and DPPH (82.6± 4.3%) scavenging activities. Findings foster the potential application of multifunctional peptides rich fermented dairy beverage developed using single strain as a dietary treatment.