QUALITY ENHANCEMENT OF APPLES USING SHORT TERM CONTROLLED-ATMOSPHERE STORAGE

Abstract

In 1989 and 1990, `Golden Delicious' apples from controlled-atmosphere (CA) storage (1% O2; 3% CO2) averaged 8.5 N firmer after 30 days and 13.5 N firmer after 60 days of storage than apples from regular-atmosphere (RA) storage. After 7 days of ambient storage, `Golden Delicious' apples from CA storage were 10.3 N firmer than apples from RA storage. Little change in color was evident in `Golden Delicious' apples from CA storage after 30 or 60 days, but a distinct increase in yellow color was evident in apples from RA storage after only 30 days. The quality (color, firmness, and acidity) of `Golden Delicious' apples stored for 30 days under CA and then 30 days under RA was superior to that of `Golden Delicious' apples after 60 days of RA storage and similar to that of `Golden Delicious' apples after 60 days of CA storage. `Granny Smith' apples, traditionally a very firm apple regardless of the type of storage, averaged 3.3 N firmer after 30 days of CA storage (1% O2; 1% CO2) and 5.8 N firmer after 60 days of CA storage when compared to apples from RA storage. Little change in color was evident in `Golden Delicious' apples regardless of storage length, but under ambient storage temperatures, `Golden Delicious' apples from CA storage maintained their green color longer. Titratable acidity of both `Golden Delicious' and `Granny Smith' apples depended on growing season, and neither `Golden Delicious' nor `Granny Smith' apples showed consistent trends in titratable acidity after either RA or CA storage.