The influence of pre-freezing temperature was studied on drying characteristics and quality of kiwifruit slices. The pore microstructure of kiwifruit slices were analyzed by scanning electron microscopy (SEM) in order to study the effect of pre-freezing temperature on porosity and fractal. The results showed that the drying rate reduced with the lower pre-freezing temperature. Quality factors, such as, the hardness and crispness increased on higher pre-freezing temperature; but the rehydration radio decreased. The sensory overall scores of kiwifruit slices processed by pre-freezing at -40 ℃ and -50 ℃ were significantly higher than -20 ℃and -30 ℃. According to the SEM, when the pre-freezing temperature was decreased, the pore structure of kiwifruit slices became smaller and their quantities increased. The pores were more regular and evenly distributed with smaller average pore area, pore perimeter, pore diameter and pore rate. It concluded that sensory quality of kiwifruit slices could be improved by reducing the pre-freezing temperature to some extent. However, the drying rate reduced, resulting in the increasing ost of energy and of production.
MAI Run-ping
,
FENG Yin-xing
,
LI Bian-sheng
. The influence of pre-freezing temperature on the characteristics of kiwifruit slices based on fractal[J]. Food and Fermentation Industries, 2018
, 44(12)
: 155
-160
.
DOI: 10.13995/j.cnki.11-1802/ts.016457
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