Preparation of resveratrol-enriched and poor allergic protein peanut sprout from ultrasound treated peanut seeds

• US pretreatment can significantly improve Res content during peanut germination.
• Allergic protein disappear entirely after 3d of US combined germination.
• US combined germination can produce hypo-allergenic and high-Res peanut food.

Peanut sprout is a kind of high quality natural food which has important effect on health-care. It contains abundant bioactive substances such as resveratrol and lower fat. Naturally, resveratrol occurs in stilbene phytoalexin phenolic compound produced in response to a variety of biotic and abiotic stresses. In this study, the influence of ultrasonic stimulation on the resveratrol accumulate in germinant peanut prepared from three varieties (FH12, FH18, and BS1016) in the dry state before steeping were investigated. All experiments were performed using an ultrasonic cleaner bath operating at three frequencies (28, 45 and 100 kHz) for 20 min at constant temperature 30 °C. The resulted amounts of resveratrol in peanut sprout were increasing by 2.25, 3.34, and 1.71 times compared with the control group of peanut germinated from FH12, FH18, and BS1016, respectively, after 3d with decreasing the amounts of allergic protein. After ultrasound, the germination rate and total sugar content increased slightly while the crude fat decreased and protein remained unchanged. Overall, the study results indicated that ultrasound treatment combined with germination can be an effective method for producing enriched-resveratrol and poor allergic protein peanut sprout as a functional vegetable.