Choi Hyuk, Na HeeSun, Kim SungHwa, Lee YoonHee, Lee JaeHwan
Department of Food Science and Biotechnology, Sungkyunkwan University, Suwon, Republic of Korea.
Food Flavor Sensory Research Center, Sungkyunkwan University, Suwon, Republic of Korea.
J Food Sci. 2021 Dec;86(12):5272-5281. doi: 10.1111/1750-3841.15964. Epub 2021 Nov 18.
The effect of microwave irradiation on the oxidative stability of tocopherol-enriched corn oil at temperatures of 60 or 100°C was evaluated using the Rancimat assay. Short durations of microwave treatment (1 min) on 10-g oil aliquots were found to increase the induction period of corn oil samples containing 500 and 1000 ppm tocopherol by 7.7% and 9.9%, respectively compared to control oils. The moisture content of tocopherol-enriched corn oil decreased by 15% compared to that of corn oil after 1 min of microwave treatment. At 100°C, 1000 ppm tocopherol-enriched corn oil received 3 min of microwave treatment had 5.8% and 9.9% lower primary and secondary oxidation products than control groups, respectively while this effect was not clearly observed for oils stored at 60°C. However, 15 min of microwave irradiation accelerated the rates of lipid oxidation in corn oils irrespective of the addition of tocopherol. Content of α- and γ-tocopherols in 1 min of microwave irradiated samples remained more by 28.8 and 5.8%, respectively than those of controls after 9 h heat treatment at 100°C. Overall, microwave irradiation within 3 min can increase the oxidative stability of 10 g-corn oils, especially at 100°C, which could be due to the reduced moisture content in the bulk oil matrix. Practical Application: A microwave oven is an irreplaceable home appliance and is widely used in households. Short time exposure to microwave irradiation can remove moisture efficiently from edible oils without the formation of oxidation products, which could increase the oxidative stability of these oils, especially under frying conditions. The results of this study can be utilized to ensure a longer shelf-life of fried products in the food industry by short time treatment of microwave irradiation.
采用Rancimat法评估了微波辐射对富含生育酚的玉米油在60℃或100℃温度下氧化稳定性的影响。发现对10克油样进行短时间（1分钟）微波处理后，与对照油相比，含有500 ppm和1000 ppm生育酚的玉米油样品的诱导期分别增加了7.7%和9.9%。经过1分钟微波处理后，富含生育酚的玉米油的水分含量比玉米油降低了15%。在100℃下，接受3分钟微波处理的1000 ppm富含生育酚的玉米油的初级和次级氧化产物分别比对照组低5.8%和9.9%，而在60℃储存的油中未明显观察到这种效果。然而，15分钟的微波辐射加速了玉米油中脂质氧化的速率，无论是否添加生育酚。在100℃热处理9小时后，微波辐照1分钟的样品中α-生育酚和γ-生育酚的含量分别比对照样品多28.8%和5.8%。总体而言，3分钟内的微波辐射可以提高10克玉米油的氧化稳定性，尤其是在100℃时，这可能是由于散装油基质中的水分含量降低所致。实际应用：微波炉是一种不可替代的家用电器，在家庭中广泛使用。短时间暴露于微波辐射可以有效地去除食用油中的水分，而不会形成氧化产物，这可以提高这些油的氧化稳定性，尤其是在油炸条件下。本研究结果可用于通过短时间微波辐照处理来确保食品工业中油炸产品的更长保质期。
