Carvacrol methyl ether, a compound from the essential oil of Gardenia jasminoides fruits, exhibits antioxidant effects in the deep-frying of Chinese Youmotou using sunflower oil

摘要

Deep-frying using sunflower oil (SFO) requires natural antioxidants, and the preparation of flavored SFO using spices and herbs offers an important method. In the present study, in the deep-frying procedure of Chinese Youmotou at 180 degrees C, improvements in the levels of total polar compounds (TPC), thiobarbituric acid (TBA), conjugated dienes, conjugated trienes, polymer, viscosity and b* of SFO samples at the 30th hour were significantly inhibited by 50.2%, 43.0%, 62.6%, 37.8%, 61.9%, 24.0% and 50.4% (p < 0.01 or p < 0.05), respectively, after the addition of Fructus gardenia (Gardenia jasminoides fruits, FGEO) essential oil at 0.12 g/kg compared with those in the no-added SFO samples (control samples). Meanwhile, the levels of L* was significantly reduced by 24.1% (p < 0.05). The sensory attributes of the fried product, Chinese Youmotou, including flavor, taste, crispness and overall acceptability, were prominently increased by 37.3%, 32.1%, 62.2% and 53.3% (p < 0.01 or p < 0.05), respectively. Moreover, improvements in the oxidative stability of SFO due to FGEO were attributed to one of its chemical constituents, carvacrol methyl ether. Consequently, SFO flavored by Fructus gardenia could be employed as a flavored vegetable oil for deep-frying procedures.