'GRANNY SMITH' APPLE (MALUS COMMUNIS, L.) PARENCHYMA: ULTRASTRUCTURE AND OSMOTIC DEHYDRATION

摘要

Granny Smith apple presents an increasing interest due to his production volume, good storage capacity and his high consumer acceptance. Osmotic dehydration allows to obtain preserved foods and at the meantime minimally processed; osmotic dehydrated foods are very interesting in the market, mainly in different products as desserts, cakes, salads, yoghurts, etc. Previously to the present work the osmotic dehydration influence had been studied on the Granny Smith apple parenchyma microstructure by Scanning Electron Microscopy (SEM) and for Cryo-Scanning Electron Microscopy (Cryo-SEM) (Rosell et al., 1994 and 1997), but one didn't have information of the ultraestructural affectation level for what is the objective of the present work. Our observations for Transmission Electronic Microscopy (TEM) show: contacts cell-to-cell and intercellular spaces are enlargement; the fibrilar structure that constitute the primary cellular wall is dispersed; the middle lamellas are destroyed too, and consequently appears numerous holes (gaps) or discontinuities in the cell wall; cannot be found components of the plasmodesmata-wall complex, cellular membranes and tonoplast are broken, collapsed and their residuals usually appear retreated toward the center of the cell. Light Microscopy (LM) shows the parenchyma deformed and in plasmolisis for the osmotic effect.