Hydroxy-sanshool compounds were extracted from the hydrodistillation residue of Z. bungeanum Maxim. pericarp (ZBM) and Z. armatum DC. pericarp (ZADC) by using ethanol-water extraction and extractions assisted with (i) enzymes, (ii) ultrasound, and (iii) enzymes and ultrasound. The yields of the hydroxy-sanshool extracts under these four extraction conditions were calculated and compared. The ultrasound-assisted enzymatic extraction was then optimized based on a Box-Behnken design. Furthermore, five hydroxy-sanshool compounds in the extracts were quantified and their pungent taste contribution value (PCV) was calculated. Oral sensory evaluation was finally performed. Compared with that of the hydroxy-sanshool extracted with ethanol-water, the yields of the samples from the extraction assisted with enzymes, ultrasound, and enzymes and ultrasound increased by 4.2-7.6%, 9.3-9.8%, and 21.5-26.2%, respectively. A maximum yield of 7.87% (w/w) was achieved by using ultrasound-assisted enzymatic extraction under the optimal conditions: 3.1% (w/w) amount of enzyme, an incubation temperature of 50.3 °C, and an ultrasound irradiation power of 207 W. The PCV of hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, hydroxy-ε-sanshool, and hydroxy-γ-isosanshool was 1153, 447, 461, 139, and 51 ml g-1 for the ZBM extract, respectively, while the PCV of these five hydroxyl-sanshools was 659 ml g-1, 575 ml g-1, not detected, 119 ml g-1, and not detected for the ZADC extract, respectively. Tingling and salivation were the main taste sensations of ZBM, whereas numbing and tingling sensations were dominant in ZADC.
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