Research on Food Manufacturing with Effect and Comparison of Microwave and Traditional Cooking Processing on Antioxidant Function of Lotus Root
Purpose: In view of the lotus root has significant antioxidant properties but if improperly cooked easily destroyed, compared with traditional cooking method, and discusses the applicability of microwave processing and establish the optimum processing conditions. Method: By setting different microwave power and heating time, handling fresh-cut lotus root vacuum packaging products with microwave, measured flavonoids, total phenolic content and DPPH clearance, and synchronization researched the traditional cook methods cooking, steaming and stir-frying, comprehensive comparison the antioxidant effect of all kinds of processed products. Results: ①Under following conditions microwave power ≥60 P, processing time≤6min, flavonoids and total phenol content were high, DPPH clearance was bigger also. ②Cooking 6min,water volume between 500-1000mL, flavonoids and total phenol contents was high, but change with the further increased water volume, the contents decrease, DPPH clearance was relatively stable, when confirmed water volume 1500mL, cooking 2-4min, flavonoids content slightly ascending, then changed into degressive changes, the change of DPPH clearance was similar. Total phenol content was decrease progressively along with extending of the cooking time. ③Handing under steaming 15min, three index of the products were high voltage products > atmospheric products, the latter's steamed time should be less than 20 min. ④Making products in oil capacity 25mL or less 3 min, with the increase of oil capacity, flavonoids, total phenolic content and DPPH clearance were progressive increase. ⑤Lotus root food antioxidant activity: steamed food < cooked food < microwave food < fried food. Conclusion: In protecting lotus root antioxidant health care function in different cropping system, microwave is a kind of superior to boiling, steaming, and pressure cooking method and second only to oil fry.