Valorisation of Coffee Pulp for Development of Innovative Probiotic Beverage Using Kefir: Physicochemical, Antioxidant, Sensory Analysis and Shelf Life Studies.

Purpose: Coffee pulp (CP), a by-product of coffee processing industry, was valorized as a functional food ingredient by exploring effects of different extractions on its phytochemicals and formulation of a novel beverage with probiotic kefir micro-organisms. Methods: Wet coffee pulp was vacuum dried, pre-treated using steam (SCP) and viscozyme (VCP) followed by aqueous extraction of its phytochemicals. Subsequently, probiotic CP beverage (PB) was formulated from SCP adding kefir cultures and evaluated for physicochemical characteristics, sensory properties and shelf life. Results: Proximate constitution of CP revealed considerable amounts of proteins (8.74 ± 1.6%), crude fiber (9.84 ± 1.8%), calcium (97.8 ± 5.2 mg/100 g) and potassium (410 ± 13.1 mg/100 g). Extraction of bio-actives using pre-treatments resulted with maximum recovery of total polyphenols (TP) and total flavonoids (TF) in SCP (14.5 ± 1.2 mg CGAE/g CP and 6.6 ± 1.2 mg CE/g CP) followed by chlorogenic acid (2.7 ± 0.5 mg/g), caffeine (2.9 ± 0.3 mg/g) and anthocyanins (0.44 ± 0.04 mg/g) corresponding to substantial antioxidant activity as compared to VCP. SCP resulted significant α- amylase (IC₅₀ = 13.2 ± 2.2 mg/ml) and α- glucosidase (IC₅₀ = 18.5 ± 2.1 mg/ml) inhibition demonstrating anti-diabetic potential. PB resulted with improved physicochemical properties and nutrients with a calorific value of 42.58 ± 15 kcal. Organoleptics recorded higher acceptance of PB and its shelf life studies of depicted survival of the organisms up to 30 days. Conclusion: Thus PB developed from CP with supplementation of kefir can serve as a novel healthy value added product providing sustainability to the coffee industry. [ABSTRACT FROM AUTHOR]