小米粥加工过程中营养成分及抗氧化活性的变化

小米加工成米粥后供人食用，为研究其在加工过程中生理活性物质的变化规律，对小米经高压蒸煮、冷冻干燥、复水加工制成速食小米粥过程中氨基酸、酚酸、黄酮含量及提取物的抗氧化能力变化进行研究。结果表明，总氨基酸与必需氨基酸含量在加工过程中无显著性差异，小米中结合态酚酸高压蒸煮后降低27.87%，对小米中自由态黄酮经高压蒸煮后降低29.57%。冷冻干燥和复水对酚酸与黄酮含量影响不显著。复水后小米粥中的香草酸含量与小米相比增长73.94%。复水小米粥中自由态与结合态酚酸提取物清除DPPH自由基能力分别比小米中降低55.83%和88.39%；高压蒸煮后自由态与结合态酚酸提取物三价铁还原能力显著下降，分别下降30.08%和39.74%；冷冻干燥和复水对酚酸提取物三价铁还原能力无显著影响。

Instant Foxtail Millet Porridge: Change of Nutritional Ingredients and Antioxidant Ability During Processing

Foxtail millet is processed into porridge for human consumption. To determine the changes of physiological activators in the process, we analyzed the contents of amino acids, phenolic acids and flavonoids and antioxidant ability of extracts of instant foxtail millet porridge at different processing stages, including high pressure cooking, freeze drying and rehydrating. The results were as follows: the total amino acids and essential amino acids had no substantial change after processing. High pressure cooking significantly influenced the bound phenolic acids and free flavonoids content, which were reduced by 27.87% and 29.57%, respectively. Freeze-drying and rehydration had little effect on the content of phenolic acids and flavonoids. Content of vanillic acid increased significantly after processing, rose by 73.94% after rehydrating. After rehydration, the DPPH scavenging ability of free and bound phenolic acid extracts were reduced by 55.83% and 88.39%, respectively. After high pressure cooking, ferric iron reduction ability of free and bound phenolic acid extracts were reduced by 30.08% and 39.74%, respectively, declined significantly, freeze drying and rehydration had no significant effect on ferric iron reduction ability of phenolic acid extracts.