Prestorage Heat Treatment of Apples

'Jonica' and 'Shampion' apples picked at optimum harvest date were subjected separately to heat treatment as an individual fruit hot water dip for 10 and 20 seconds. Following that, fruits were cooled, placed in lots in crates and stored under conditions recommended in Poland. Respective samples of non treated fruits and heat treated were subjected to quality evaluations at harvest, after storage and after simulated shelf life. The main effect of heat treatment was total reduction of fruit spoilage due to storage diseases, whereas non treated fruits were affected by bitter rot (Gloeosporium), gray mold (Botrytis) and blue mold (Penicillium) respectively. After storage and simulated shelf life period 'Shampion' treated fruits retain higher flesh firmness than untreated ones. Soluble solids content of treated 'Shampion' fruits were higher than for untreated fruits. The soluble solids content in 'Jonica' fruits treated for 10 s was lower than treated for 20 s and control. Titratable acidity of heat treated fruits of 'Shampion' were similar to non treated apples, and for 'Jonica' were higher than control (except fruits treated for 20 s and analysed after storage).