In this paper

dehydration characteristics and microstructure variation of broad bean seeds under low temperature vacuum environment were examined. The dehydration experiments were performed at 0

4

and 8 ℃under a vacuum of 97 kPa. The moisture ratio and shrinkage of the samples were determined every 30 min. Scanning electron microscopy (SEM) was used to obtain the images of broad bean seed cells. The structural parameter distribution curves of broad bean cells at different moisture ratios were obtained by using the image processing technique. The effects of the vacuum environment on the dehydration characteristics and cell structural parameters of broad bean seeds were analyzed. The results showed that during dehydration

the moisture ratio exponentially decreased

and the Page model exhibited the best fitting effect. Thus

the shrinkage gradually increased first. Subsequently

the variation tended to be gentle. Although the main distribution intervals of size parameters

such as cell area

perimeter

and diameter fluctuated within a small range

the overall trend was decreased. Thus

the data distribution was gradually concentrated. Furthermore

the change in cell shape parameters was low

the roundness and elongation ranged within 10%

and the compactness was almost constant.