Impact of mass transport on microstructure of Granny Smith apple parenchyma during osmotic dehydration

The chemical components of foods are organized in microscopic structures that can modify mass transfer. The study of material penetration in foods can be made using X-ray microanalysis. In order to study the microstructural behaviour when fruit was osmotically dehydrated, a glucose molecule modified with chloral (1,2-O-2',2',2'-trichloroethylidene-alpha-D-glucofuranose) was used as an osmotic standard with chlorine detectable by energy-dispersive X-ray analysis. Parenchyma of Granny Smith apple is a simple tissue, so it was chosen as reference. The results show that both the apoplastic and symplastic routes played an active role in mass transfer. The osmotic agent penetrated both the symplast and apoplast well into the depths of the fruit, although greater deterioration of cells was observed near the surface. (C) 2003 Society of Chemical Industry.