The effects of α‐L‐rhamnosidase, β‐D‐glucosidase, and their combination on the quality of orange juice

The naringinase, a desirable candidate for citrus juice debittering, consists of α-L-rhamnosidase and β-D-glucosidase. This study aimed to elucidate the effects of α-L-rhamnosidase, β-D-glucosidase, and their combination on naringin, polyphenols, antioxidant activity, and aroma quality. The α-L-rhamnosidase and the two enzymes combination reduced the naringin concentration from 356.33 to 10.52 and 4.17 mg/L, respectively. The α-L-rhamnosidase, β-D-glucosidase, and their combination significantly increased the antioxidant activity. The unpleasant cooking note was significantly weakened and the floral note was increased after three treatments. The combinational treatment increased the sweet note greatly. The substrate competition between α-L-rhamnosidase and β-D-glucosidase may help to explain the inconsistencies of the polyphenols, antioxidant activity, and aroma quality after single enzyme or combined enzymes treatments. The results indicated that taste, antioxidant activity, and aromatic quality were well improved by the combined treatment than either α-L-rhamnosidase or β-D-glucosidase treatment, providing an attractive reference for debittering orange juice. Practical applications The work showed that the combined treatment of α-L-rhamnosidase and β-D-glucosidase was better to remove the bitter taste of citrus juice than the solo treatment with α-L-rhamnosidase or β-D-glucosidase in regarding with taste, antioxidant activity, and aromatic quality. It helps to better the quality of citrus juice with enzymatic treatment.