Scientia horticulturae vol:85 issue:3 pages:217-229
The effects of relative humidity (RH) on the quality of 'Braeburn' and 'Jonagold' apples were studied at 20 degrees C under 30, 65 and 95% RH conditions. The aim of the research was to assess the effects of RH on apple quality under retailers' shelf temperatures. Mealy texture may develop by holding apples at high RH (95%), and 20 degrees C fur some time depending on the cultivar. The 65% RH treatment is a typical RH for shelf life and 30% is a low RH condition. Apple firmness, expressible juice content, weight loss, pH, soluble solids content (SSC), and some other quality parameters were determined instrumentally. Scanning electron microscopy (SEM) was applied to investigate the structural changes at the level of the cell wall. The RH had significant effects on weight loss, firmness, and SSC values. Acoustic non-destructive measurements showed that the firmness of apples decreased mon slowly at higher RH, and the weight loss was faster at low RH for both apple cultivars. Mealiness was observed under high RH (95%) and was associated with low tensile strength and an increase of cell separation following the simulated shelf storage. Higher RH could maintain apple firmness and weight better than lower RH but it tended to promote the development of mealy texture at 20 degrees C. (C) 2000 Elsevier Science B.V, All rights reserved.