煎炸不同食材对玉米油品质的影响

EFFECT OF DIFFERENT FOOD MATERIALS ON THE FRYING QUALITY OF CORN OIL

以玉米油间歇煎炸不同食材(薯条、豆腐、鸡翅和油条)8 h,通过对煎炸油的色泽、酸价、羰基价、脂肪酸组成及维生素E含量的检测分析,对比研究不同食材对煎炸油品质的影响.结果表明:不同种类食材对油样的各项指标均有不同程度的影响,食材对玉米油的色泽、酸价、羰基价、总维生素E含量均具有显著影响,4种食材煎炸油样最终的色泽(OD448 nm)加深程度依次为:豆腐>鸡翅>薯条>油条,4种食材煎炸油的酸价增大顺序依次为:豆腐>薯条>鸡翅>油条,羰基价增大顺序依次为:鸡翅>薯条>豆腐>油条.

The present study was to investigate the the effects of four typical frying food（dough sticks, fries, tofu, chicken wings） on the frying quality of corn oil during the intermittent frying by determining the quality indexes of corn oil, including color, acid value, carbonyl value, fatty acid composition and Vitamin E content. The results showed that four food ingredients all presented significance impacts on the frying physicochemical indexes of the corn oil. The final color （OD44s ） deepen degrees of the four oil frying ingredients were as follows： tofu 〉 chicken wings 〉 fries〉 dough sticks. The highest water content was the main reason of the tofu oil sample absorbance values higher than the other samples. The order of acid value increase of the four frying oil samples was： tofu 〉 fries 〉 chicken wings 〉 dough sticks. The moisture accelerated the hydrolysis of frying oil and a large amount of free fatty acids produced. The highest water content of tofu caused the acid value in the frying process was always higher than other samples. Carbonyl value was the most sensitive index to evaluate the degree of oil decomposition. The order of the carbonyl value increase was： chicken wings 〉 fries 〉 tofu 〉 dough sticks. Percentage of total SFA of corn oil frying food （ C8：0, C 14 ： 0, C 16 ： 0, C 18：0, C20 ： 0, C22 ： 0, C24：0 ） and total MUFA （ C18：l,C16：l）were relatively increased,while the percentage of total PUFA （C18：2,C18：3） were relatively reduced and the percentage of total TFA were relatively increased. The increase of total trans fatty acid content was： tofu 〉 dough sticks 〉 fries 〉chicken wings （1.35 〉 1.33 〉 112 〉 0.64） （%）. The order of the decrease level of the vitamin E content of the four corn frying oil was as follows： chicken wings 〉 dough sticks 〉 fries 〉 tofu.