研究了蓝莓的液氮式流态化速冻加工工艺及其冻后样品在贮藏期间的品质变化规律。多元线性回归分析显示了液氮式流化床速冻蓝莓适宜的工艺条件为:冻结温度=-40℃、风机风速=4.5 m/s、床层高度=3.6cm。环境扫描电镜(ESEM)显示了流化床速冻蓝莓的内部微观结构在致密性、均匀性和破坏性上优于-18℃冰箱慢速冻结。对贮藏期间的样品采取感官检验方法,通过对蓝莓的外部颜色、内部颜色、硬度和外观品质等评分,结果表明流化床速冻蓝莓的品质优于-18℃冰箱慢速冻结的蓝莓。

Liquid nitrogen spraying fluidized freezer was used for individual quick freezing( IQF) of blueberries. Freezing process technology and quality changes of frozen samples during storage stage were analyzed in this paper. Multiple linear regression analysis indicated that the suitable process freezing temperature、wind speed and bed height for quick-freezing blueberries in LN 2-spraying fluidized freezer were- 40 ℃,4. 5 m / s and 3. 6 cm. Environmental scanning electron microscopy( ESEM) results showed that the inner microstructure of the fluidized quick-frozen blueberries had better compactness,uniformity and destructiveness than that of control group which blueberries were slowly frozen in- 18℃. Sensory evaluation were used to score the difference of blueberries in external and internal color,firmness and exterior quality between the fluidized quick-frozen and slow-frozen in- 18℃. The results show that the quality of the fluidized quick-frozen blueberries was better than that of the control group.