The low-field nuclear magnetic resonance technique was used to analyze the moisture content inside broad bean seeds and the deformation mechanism in each phase. The characteristics of seed dehydration and deformation under different low temperature environments and different vacuum conditions were studied. The results show that the z (thickness) direction shrinkage varies the most and is susceptible to the dehydration environment. The combined water content does not change significantly during the vacuum dehydration process. The semi-bound water content shows an increase-decrease trend and the free water content continues to decrease to zero. The free flow of free water between cells can enhance respiratory metabolism and nutrient consumption

and hence should be discharged as soon as possible. The transformation and escape of semi-bound water plays a key role in maintaining the morphology of broad bean seeds. The escape of combined water is directly related to cell rupture that is vital to the survival of the seed. The cell membrane rupture in the broad bean seed has three stages

and the water transport interacts with it. To maintain seed activity

the dehydration should be completed before the third stage.