Effect of growing season, harvest maturity, waxing, low O2 and elevated CO2 on flesh browning disorders in `Braeburn' apples
O. L. Lau
Postharvest Biology and Technology. Volume 14, Issue 2, October 1998, Pages 131-141.
1998
บทคัดย่อ
British Columbia-grown `Braeburn' apples (Malus×domestica Borkh.) stored for 6 months in air at 0°C were, on average, 70 N in flesh firmness and had 0.48% titratable acidity. Fruit held in 1.2 or 1.5% O2+1.0 or 1.2% CO2 controlled atmosphere (CA) storage were 8 N firmer, 20% higher in titratable acidity, and had significantly less core browning and superficial scald than fruit held in air for the same period. However, CA-stored fruit were highly susceptible to Braeburn browning disorder (BBD) and internal cavities (IC) after cool growing seasons [1993, 1995, and 1996; <1300 degree-days >10°C (DD10) accumulated between May 1 and harvest]. Susceptibility of fruit to BBD and IC was greatest in late-harvested fruit (starch index>2.5 on a 0¯9 scale) stored in 3.0% CO2 and 1.5% O2. Storage at 1.7, 2.0, 3.0 and 4.0°C did not decrease BBD or IC incidence and tended to increase core browning (1996) and flesh softening (1994 and 1996) compared with fruit kept at 0°C. Coating fruit with Shellac wax, but not Carnauba wax, increased BBD in air-stored fruit. Following a cool growing season it is recommended that `Braeburn' apples be harvested at starch index values between 2.5 and 3.0 and stored in air storage at 0°C to avoid the risks of scald, BBD and IC. The fruit may be stored in <1.0% CO2 (preferably close to 0.1%) and >1.5% O2 after warm seasons (>1300 DD10).