Quality of diphenylamine treated Granny Smith apples in relation to the composisiton of the storage atmosphere

Abstract

New South Wales grown Granny Smith apples were stored for seven months in three seasons. The effects of four controlled atmospheres and two air storage temperatures on final fruit quality and on development of senescent disorders were studied. To minimise superficial scald, to which the variety is very susceptible, the fruit was wrapped in diphenylamine wraps prior to storage. Assessment of quality after storage was made by panel judgments of appearance and edibility. The effects of the storage conditions on the development of disorders were assessed by scoring methods. In general, controlled atmosphere storage reduced the development of senescent disorders and proved superior to air storage in the maintenance of fruit qualify. Atmospheres containing carbon dioxide best preserved external appearance but an atmosphere of low oxygen with carbon dioxide removed resulted in superior internal quality. Of the treatments studied 5 per cent carbon dioxide with 2.5 per cent oxygen gave best overall fruit quality.