Use of oils in the diet requires their protection against oxidation under conditions of high temperature and light. The expiration date is different depending on the type of oil. The presence of light and heat affects its quality: acid value, peroxide value and antioxidant capacity due to the presence of natural oils, antioxidants such as tocopherols, polyphenols, vitamin C, and so on, or artificial, added during the technological processes of obtaining them. Changes in acid value and peroxide may be linked to the antioxidant content assessed by measuring antioxidant activity by DPPH method. Oxidative stability of sunflower oil, corn oil, extra virgin olive oil, grape seed oil and nut oil was studied before and after keeping them in oven for 5 days at 50 o C. Under these conditions of accelerated oxidation, oxidative stability was evaluated by measuring peroxide value, antioxidant activity of free acidity. From analyzes it came out that coconut oil has the highest antioxidant capacity and the lowest variation of peroxide value and free acidity in mentioned conditions.
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机译：在饮食中使用油脂需要在高温和光照条件下提供抗氧化保护。到期日期因机油类型而异。光和热的存在会影响其质量：由于存在天然油，生育酚，多酚，维生素C等抗氧化剂（例如生育酚，多酚，维生素C等）或在制造过程中添加的人工添加的酸，其酸值，过氧化物值和抗氧化能力他们。酸值和过氧化物的变化可能与通过DPPH方法测量抗氧化剂活性而评估的抗氧化剂含量有关。研究了葵花籽油，玉米油，特级初榨橄榄油，葡萄籽油和坚果油在50 o C下在烤箱中放置5天前后的氧化稳定性。在这些加速氧化的条件下，通过测量氧化稳定性来评估过氧化物值，游离酸的抗氧化活性。从分析中可以看出，在上述条件下，椰子油具有最高的抗氧化能力，过氧化值和游离酸度的变化最小。
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