β‐ d ‐glucosidase can release aroma precursors to improve the flavor of plant food, but the hydrolysis efficiency of the enzyme is low; the purpose of this study was to improve the enzyme activity using ultrasound. The effects of ultrasound parameters on β‐ d ‐glucosidase activity were investigated, and the respective structures of enzyme activated and enzyme inhibited were further analyzed. Low temperature (20–45°C), low ultrasonic intensity (<181.53 W/cm 2 ), and short treatment time (<15 min) led to the activation of β‐ d ‐glucosidase, whereas high temperature (45–60°C), high ultrasonic intensity (>181.53 W/cm 2 ), and long treatment time (>15 min) led to its inhibition. Application of ultrasound lowered the optimum temperature for β‐ d ‐glucosidase activity from 50 to 40°C. Ultrasound did not change the primary structures of the enzyme, but changed the secondary structures. When ultrasound activated β‐ d ‐glucosidase, the α‐helix contents were increased, the β‐fold and irregular coil content were reduced. When ultrasound inhibited β‐ d ‐glucosidase, the contents of β‐folds were increased, the α‐helix and irregular coil contents were reduced.. In summary, activation or inhibition of β‐ d ‐glucosidase under ultrasound was determined by the ultrasound conditions. This study suggests that ultrasound combined with β‐D‐glucosidase can be used in aroma‐enhancing.

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The synergistic effects of ultrasound and β‐d‐glucosidase in aroma of orange juice were investigated. β‐d‐Glucosidase significantly increased the content of ester, aldehyde, alcohol, terpene, acid, and phenol, and insignificantly increased the ketone content in orange juice. Enzyme‐treated orange juice, compared with fresh untreated orange juice, was found to contain 15 novel aroma compounds, whereas three aroma compounds disappeared. Ultrasound improved the enzymatic action and the retention of more active flavors in juice than treatment with enzyme alone. However, simultaneous ultrasound and enzyme treatment decreased aroma quality. Therefore, the choice of the mode of ultrasound treatment is highly important. The present investigation will provide a reference for aroma‐enhancing application of ultrasound combined with β‐D‐glucosidase. Practical Application The study supplies a reference method for the aromatization of fruit juice.