1996 Volume 22 Issue 2 Pages 85-89
Tangor 'Kiyomi' (Citrus sinensis × C. tangerina) fruits were stored at 5°C for 3 months and subsequently transferred to 8°C or 20°Cwith/without polyethylene film packaging (LDPE-20 μm), respectively. The fruits transferred to 20°C showed more severe rind-oil spot injury than those to 8°C, and the packaging with LDPE reduced the injury both fruits stored at 20°C and 8°C. The rate of K ion leakage from the fruits showed the increasing and sharp peak at 2 days for 8°Cand 5 days for 20°C after transferring. The peak of leakage for 20°C was higher than that of 8°C and the rate of leakage of packed fruit was lower than that of non-packed fruit both at 20°C and 8°C. The flavedo tissues were prepared for observation by scanning electron microscopy (SEM). The surface of sound fruit was covered by a thick, waxy, highly patterned cuticles and the stomata scattered over the surface. The SEM showed that the epidermis cells, parenchyma cells, and oil glands remained intact in the cross section of sound fruit. The pit between oil gland and partially ruptured cuticles on the surface were observed for the injured fruit showing rind-oil spot and slight discolor. The destructed parenchyma cells were observed but the epidermis cells remained intact in the cross section of the slight injured fruit. The SEM showed the severely ruptured cuticles on the surface and severely destructed parenchyma cells of the severely injured fruit. The epidermis cells remained intact in the severely injured fruit and the pit in rind-oil spot injury commenced with the destruction of parenchyma cells locating several layers inside the surface.
