Optimization of multi-enzyme coupled debittering process: Effect on bitterness and bioactive components of Shatianyu (Citrus grandis L. Osbeck) whole fruit powder

A debittering method by multi-enzyme coupled hydrolysis for Shatianyu ( Citrus grandis L. Osbeck) whole fruit powder (SWFP) was established. Shatianyu whole fruit homogenate (SWFH) was hydrolyzed by pectinase and cellulase (1:1, w /w, pH 4.5, 50 °C for 2 h). The mixture was then hydrolyzed by naringinase under the optimal conditions: naringinase addition amount of 0.38% ( w /w FW), hydrolysis time for 3.0 h, and hydrolysis temperature at 50 °C. Subsequently, the hydrolyzed products were freeze dried to obtain PCNE-SWFP. Compared with SWFP, the major bitter flavonoids including naringin, melitidin and cigranoside B in PCNE-SWFP were degraded by 40.1%, 37.9% and 49.7%, respectively, and bitterness intensity was reduced by 68.7%. Notably, PCNE-SWFP still showed high total flavonoid content (18.2 mg CE/g DW), also exhibited an increased soluble dietary fiber content, antioxidant activity, as well as water adsorption, water swelling and oil adsorption capacity compared with SWFP.