微波与烤箱烘烤灭酶对新水剂法提取南瓜籽油的影响

为了比较不同的灭酶方式在新水剂法提油中的应用效果,以南瓜籽仁为原料,经微波(不同微波功率和微波时间)和烤箱烘烤(不同烘烤温度和烘烤时间)处理后,采用新水剂法提取南瓜籽油,测定了南瓜籽脂肪酶活性、南瓜籽油提取率、南瓜籽粕的蛋白质溶解度和南瓜籽油的理化指标。结果表明:微波处理最佳条件为微波功率480 W、微波时间60 s,在此条件下南瓜籽油提取率为95.51%,而烤箱烘烤处理最佳条件为烘烤温度110℃、烘烤时间10 min,在此条件下南瓜籽油提取率为94.13%,二者均显著高于未灭酶处理时的南瓜籽油提取率(90.54%);与烤箱烘烤灭酶处理相比,微波灭酶处理获得的南瓜籽油具有更低的过氧化值和更高的黄酮含量、总酚含量、DPPH自由基清除率,微波灭酶处理获得的脱脂粕的蛋白质溶解度更高,且耗电量只有烤箱烘烤灭酶的6.15%。在采用新水剂法提取南瓜籽油时,微波灭酶优于烤箱烘烤灭酶。

Finite Element Modeling of Solar Powered Injera Baking Oven for Indoor Cooking

In this paper, a 2D transient finite element analysis was carried out for a new type of solar powered injera baking system. In the proposed system （currently under development）, heat transfer oil is heated using solar energy by parabolic trough and the oil circulates through the space below the baking pan in the kitchen. Based on previous finite element study on existing electric injera baking pans, a new type of baking pan made from ceramic with 8 mm thickness was manufactured and used for the proposed system. The model was further extended to study the heat up time and temperature distributions during initial heat up and cyclic baking of the new model. The proposed baking pan that uses solar energy gives acceptable heat up and baking time compared to existing conventional baking methods. Generally, the finite element model predicts well the temperature distributions during initial heat up and cyclic baking.