真空油炸过程中干燥特性和产品品质变化的研究

研究了胡萝卜脆片真空油炸过程中干燥特性和产品品质的变化,结果表明:真空油炸过程属于传统的降速干燥过程,其水分和脂肪的变化符合一级反应动力学规律,利用非线性回归法求解得到了胡萝卜脆片水分和脂肪含量、干燥速率随油炸时间变化的方程;随着油炸时间的延长,胡萝卜脆片直径不断减小,厚度不断增加,油炸20min后,其直径和厚度皱缩度分别达到6%和4.5%;真空油炸胡萝卜脆片气孔数量不断增加,细胞结构变形程度增强。真空油炸过程中胡萝卜脆片脂肪主要分布于脆片的表面,冷却过程中脂肪逐渐向中心渗透,中心脂肪含量可达到60%。

Study on the drying characteristics and products quality changes during vacuum frying

The drying characteristics and products qulities of carrot chips during vacuum frying were studied.The results showed that vacuum frying pocess belonged to traditional falling rate drying and corresponds with the first order reaction kinetics.The equations of moisture content,fat content,drying ratio of vacuum fried carrot chips as function of frying time were established.The value of diameter decreased and the thickness increased with the increasing in the frying time.The shrinkage of diameter and thickness reached 6% and 4.5% respectively,after frying for 20min.With the increasing in frying time,the number and size of pore increased gradually and the degree of cell deformation reinforced.During vacuum frying,the fat mostly distributed the surface of carrot chips and during the cooling process,fat gradually filtered to center and the center fat content could reached to 60%.