Moisture apple tissues

Salvatori, D., Andres, A., Chiralt, A., and Fito, P. 1999. Osmotic dehydration progression in apple tissue. I. Spatial distribution of solutes and moisture content. J. Food Engineer. 42, 125-132. 

Bruises are clearly visible in NMR images of apples, peach, Asian pear, and onion [14]. A relatively new bruise is brighter than the surrounding tissue due to a decrease in the magnetic susceptibility variations in the tissue. This decrease is a result of cell damage and subsequent diffusion of moisture into air pockets in the tissue of fruit [15]. However, the very old bruise does not show up as a brighter region, but instead appears darker because of dehydration[14]. 

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