Control of Low-Temperature Injury in the Victoria Plum

Abstract

IT is well known that many kinds of fruit and vegetable after picking may be damaged during storage at low temperature above the freezing point. The phenomenon has been widely studied, and there is a considerable literature on the low-temperature injury relations of the apple, plum, peach and grapefruit. That the conditions known as low-temperature internal breakdown of the apple and plum, as well as woolliness of peaches and pitting of the rind of grapefruit are the final and visible result of a series of reactions deriving from an initial and sustained shift of metabolic balance, has seemed fairly evident. But observations of the influence of external factors of primary importance, namely, level of temperature and duration of exposure as well as of internal factors such as varietal type, degree of ripeness at picking, etc., have revealed a considerable complexity which cannot be elucidated by any simple hypothesis. It has, for example, been observed that after a limited period of exposure, the maximum percentage of injured fruits (plums and grapefruit) will often be found in samples subjected to storage at temperatures of an intermediate range. But after more prolonged exposure the highest proportion of injured fruits is found at the lowest temperature of storage.