Effects Of Cooking Methods On Antioxidant And Hypoglycemic Activities Of Brown Rice Phenolics And The Development Of Brown Rice Soft Cracker

DM is a common endocrine disorder caused by the interaction of genetic and environmental factors,and has become the third most serious chronic and common disease in the world after tumors and cardiovascular diseases that endanger human health.Recent researches have verified that brown rice has useful advantages and can effectively prevent various chronic diseases like polygenic disease,hyperlipidemia and hypertension.Its phenolic resin compounds,play a significant role in reducing the danger of chronic diseases like kind Ⅱ genetic defect.In this study,we collected brown rice from five Liaoning regions,analyzed and compared the polyphenol content,compositional differences,antioxidant and hypoglycemic activities of five types of brown rice,and explored the effects of four cooking methods（atmospheric cooking,autoclaving,microwave atmospheric cooking and microwave autoclaving）on the antioxidant and hypoglycemic activities of brown rice phenolic extracts;based on this,we developed a new brown rice product,brown rice soft snow cake.The most results square measure as follows.（1）Determination of the polyphenol content of five brown rice species.The results showed that the total phenolic content ranged from 5.97 ± 1.06 to 8.29 ± 0.97mg/g.Type-968 had the simplest total phenoplast content.The main monomeric compounds of brown rice phenolics consisted of ferulic acid,gallic acid,p-coumaric acid and p-hydroxybenzoic acid,and also the content of acid was on top of that of the opposite 3 synthetic resin acids.（2）Determination of antioxidant activity of five types of brown rice.Two evaluation methods,DPPH and hydroxyl radical scavenging capacity,were used to test the antioxidant capacity of the brown rice extracts.The results showed that the five brown rice sample extracts showed scavenging activity against both free radicals in a concentration-dependent manner.The antioxidant activities of the five brown rice types were significantly different,but the trend was consistent with the total phenolic content,in the order of Type-968 > Liaoxing Mix > Liaoxing 1 > Changlixiang >Type-619.（3）Hypoglycemic activity of five types of brown rice and hypoglycemic study of IR-L02 model.The hypoglycemic activity was examined by α-glucosidase andα-amylase activity inhibition assay and glucose depletion assay in insulin resistant IR-L02 cells.The results showed that the polyphenol extracts of all five brown rice samples had inhibitory effects on both enzyme activities,with stronger inhibitory activity on α-glucosidase than α-amylase,and the inhibition rate of Type-968 on the enzyme was higher than that of the other four species.The glucose consumption rate of insulin-resistant cells increased significantly after treatment of the five brown rice polyphenol samples,ranging from 9.21% to 51.69%,with Type-968 showing the greatest elevation.（4）Determination of phenolic content of brown rice by different cooking methods.The phenolic substances in the atmospheric cooking samples,high-pressure cooking samples,microwave atmospheric cooking samples and microwave high-pressure cooking samples were chemically extracted and measured,and the results showed that each region cookery and aggressive cookery reduced the entire synthetic resin content of rice,with atmospheric cooking slightly damaging brown rice polyphenols more than high-pressure cooking;microwave treatment（microwave atmospheric cooking and microwave high-pressure cooking）significantly increased the total phenolic content;compared with Compared with the other three cooking methods,the microwave autoclaving can increase the total phenolic content of brown rice to the largest extent.（5）The antioxidant and hypoglycemic activities of brown rice phenolics were measured by different cooking methods.The results showed that the antioxidant test showed that the scavenging ability of brown rice phenolic extracts for two free radicals in different cooking methods was microwave high-pressure > microwave atmospheric pressure > high-pressure cooking > atmospheric cooking;high-pressure cooking showed stronger scavenging activity than atmospheric cooking;microwave pre-cooking could improve the antioxidant activity.The hypoglycemic enzyme inhibition test showed that the inhibition rate of the four cooked brown rice extracts for the two enzymes was positively correlated with the phenolic content,in order of microwave high pressure > microwave normal pressure > high pressure steaming >normal pressure steaming,the inhibition rate of microwave high pressure steaming was significantly higher than the other samples,and the inhibition rate of the cooked brown rice samples was lower than that of the drug acarbose,and its inhibition effect was more desirable as food.The IR-L02 model was established,and the IR-L02 glucose consumption test of brown rice extracts in four cooking methods showed that the consumption rate of glucose in insulin-resistant cells was significantly increased after the treatment of all four samples.（6）In vitro digestion tests of brown rice samples with different cooking methods were conducted to determine the phenolic content,antioxidant and hypoglycemic activities of the four digested samples.The results showed that the total phenolic content,free radical scavenging rate,enzyme inhibition rate and IR-L02 glucose consumption rate of the digested brown rice samples were all increased to different degrees compared with those before digestion.（7）To develop brown rice soft cracker,the optimum process parameters were determined,i.e.,microwave cooked and sprouted brown rice flour to wheat flour mass ratio of 3:7,microwave cooked and sprouted brown rice enzyme of 5 g,whole potato flour of 10 g,and grain ruan flour of 5 g.The other ingredients were added in the amounts of yeast 1.5 g,water 56 g,xylitol 10 g,butter 6 g,salt 0.6 g,and milk powder2.5 g.The total polyphenol content of brown rice soft cracker was 12.87 mg/g,γ-aminobutyric acid content was 29.23 mg/100 g,protein content was 8.45 g/100 g,and dietary fiber content was 2.72 g/100 g.The nutritional composition was higher than that of commercially available soft crackers.The hardness and cohesiveness were lower than the corresponding measured values of commercially available soft crackers,and the elasticity,chewiness,recovery,water holding capacity and specific volume were higher than the corresponding measured values,and the overall quality of soft cracker was significantly improved.