深度油炸过程煎炸油的氧化及其对油炸外裹糊鱼块品质的影响

Oxidation of frying oil during deep-fat frying and the effects of frying oil oxidation on the quality attributes of fried batter-breaded fish nuggets

目的探究深度油炸过程煎炸油的氧化,并进一步研究煎炸油氧化对油炸外裹糊鱼块品质的影响。方法分别采用棕榈油、大豆油、葵花籽油、小麦胚油在150、160、170、180、190℃下油炸外裹糊鱼块,测定煎炸油的酸价、过氧化值、黏度、介电常数以及油炸外裹糊鱼块外壳的水分含量、油脂含量、表面色度。结果随着油炸温度的升高,煎炸油的游离脂肪酸含量增加,导致煎炸油的酸价、黏度和介电常数升高,过氧化值呈现波动下降的趋势;油炸外裹糊鱼块的水分含量逐渐减少,油脂含量逐渐增加,L*和b*呈递减趋势、a*呈递增趋势,且使用4种煎炸油的各项指标存在明显差异。结论煎炸油的油炸温度和不饱和脂肪酸含量显著影响了煎炸油的氧化,导致外裹糊鱼块深度油炸过程中水分蒸发和油脂吸收有明显差异,最终影响了油炸外裹糊鱼块的品质。

Objective To explore the oxidation of frying oil during deep-fat frying, and further study the effects of frying oil oxidation on the quality of fried batter-breaded fish nuggets. Methods Palm oil, soybean oil, sunflower seed oil and wheat germ oil were respectively used to fried batter-breaded fish nuggets at the temperatures of 150,160, 170, 180, and 190℃, and the acid value, peroxide value, viscosity and dielectric constant of the frying oil as well as the moisture and fat content and surface color of the shell of the fried batter-breaded fish nuggets were measured. Results With the increase of frying temperature, the free fatty acid content of frying oil increased, which led to the increase of acid value, viscosity and dielectric constant of frying oil, and the peroxide value fluctuated and decreased. The moisture content of the fried batter-breaded fish nuggets gradually decreased, and the fat content gradually increased. The L* and b* values showed a declining trend, and the a* value showed an increasing trend.Significant differences were observed in various indicators when the 4 kinds of frying oils were used. Conclusion The unsaturated acids content of frying oils and frying temperature significantly influenced the oxidation of frying oil, led to the significant difference in moisture evaporation and fat absorption of fried batter-breaded fish nuggets during deep-fat frying, thereby changing the quality attributes of fried batter-breaded fish nuggets.