不同油脂及抗氧化剂对韧性饼干氧化变质的影响

Effects of Different Oils and Antioxidants on Oxidative Deterioration of Toughened Biscuits

摘要:

本文研究了不同油脂及抗氧化剂对于韧性饼干在65 ℃下氧化变质的影响。通过测定该饼干在65 ℃保存下酸价、过氧化值、水分含量以及感官评分四项指标的变化，确定饼干氧化变质的速度。试验发现饼干中添加黄油时四项指标变化最为缓慢，65 ℃下可保存54 d；添加豆油时四项指标变化相对较快，65 ℃下可保存48 d。看来饱和脂肪酸含量高的油脂的氧化速度较慢，制作出的饼干变质慢，保质期长；不饱和脂肪酸含量高的油脂的氧化速度较快，制作出的饼干变质快，保质期短。所有抗氧化剂都具有抗氧化效果：合成抗氧化剂中TBHQ的效果最好，天然抗氧化剂中茶多酚的效果最好；当0.010% TBHQ结合0.020%茶多酚复配使用时，抗氧化效果最明显，氧化变质最慢，饼干在65 ℃的储藏下可保存60 d。因此，不同油脂及抗氧化剂对饼干的氧化变质都有影响。该研究为延长饼干的保质期提供参考。

Abstract:

In this paper, the effects of different oils and antioxidants on the oxidative deterioration at 65 ℃ of toughened biscuits were studied. The rate of oxidative deterioration of the biscuits was determined through analyzing the changes in acid value, peroxide value, water content and sensory scores of biscuits at 65 ℃. It was found that when the butter was added to biscuits, the changes in the four indices were slower with a shelf life of 54 days at 65 ℃, whereas, the changes in the four indices were faster upon the addition of soybean oil with a shelf life of 48 days at 65 ℃. It seemed that addition of oil with a high saturated fatty acid content led to a lower oxidation rate, slower oxidation in biscuit and thus a longer shelf life; adding oil with a high unsaturated fatty acid content caused a higher oxidation rate, faster oxidation in biscuit and consequently shorter shelf life. All the tested antioxidants exhibited anti-oxidant effects: TBHQ was the best antioxidant among the synthetic antioxidants, whilst tea polyphenols were most powerful among the natural antioxidants. The combined use of 0.010% TBHQ and 0.020% tea polyphenols in biscuit making led to the greatest antioxidative effect with the slowest oxidation in biscuits and a shelf life of 60 days at 65 ℃. Therefore, different oils and antioxidants exerted impacts on the oxidative deterioration of biscuits. This study provides indicative information for extending the shelf life of biscuits.