Study On Material、Processing Technology And Vitro Anti-oxidation Effect Of Selenium-rich Red Rice Instant Porridge

Red rice has the functions of health-care, beauty, anti-aging and so on. Selenium is an essential trace element for human and animals, and it also participate in the clearance of free radicals and reduces oxidative damage of organism. In this thesis,54 paddy varieties (52 red rice varieties,2 black rice varieties) were selected as samples. The excellent germplasm resources of red rice which possess strong selenium enriching ability and high score of sensory evaluation after being processed into instant porridge were screened out through spraying 100 mg/kg sodium selenite solution at the full heading stage. Then the instant porridge processing parameters were optimized by response surface method, and a study on the anti-oxidant activity of red rice instant porridge was conducted. Results are as follows:1. Determination of selenium content and sensory evaluation results indicated: The red rice variety 4D1253 showed optimal performance, selenium content is 0.8555 mg/kg after selenium enriched (the highest is 0.9121 mg/kg, and the lowest is 0.2582 mg/kg), comprehensive sensory score is 56.2 points after processed into instant porridge (the highest is 57.7 points, and the lowest is 36.7 points).2. Correlation analysis between selenium content and its color of selenium-rich red rice varieties showed:there was significant (0.01<p<0.05) positive correlation between selenium content and color value a1*, r=0.289; Very significant (p<0.01) negative correlation between selenium content and the total color difference (?)E1*, r=-0.508.3. Influence of processing technology on the sensory evaluation score of red rice variety 4D1253 was studied through single factor experiments, and optimized processing parameters were obtained by using the response surface method:High pressure steam time A= 15.0 min, First microwave time B= 140.0 s, Second microwave time C= 150.0 s. Sensory evaluation score of product according to the process parameters was 62.5 points, and it was basically consistent with the prediction results of response surface.4. In vitro anti-oxidant capacity determination results indicated:When the sample extracts concentration was 10 mg/ml, the DPPH free radical clearance of 4D1253 se-enriched instant porridge was 56.8%, higher than ordinary instant porridge. But the total antioxidant capacity and·OH scavenging ability of 4D1253 se-enriched instant porridge were 0.63 U/mg-,0.93 U/mg, weaker than ordinary instant porridge(0.70 U/mg、 1.02 U/mg); the superoxide free radical clearance was 25.3%, lower than ordinary instant porridge(30.6%).