Reduction of superficial scald of apples with vegetable oils
K. J. Scott, C. M. C. Yuen and G. H. Kim
Postharvest Biology and Technology Vol: 6 Issue: 3-4 Pages: 219-223.
1995
บทคัดย่อ
Five vegetables oils were applied by hand to Granny Smith apples that were highly susceptible to superficial scald and stored at 0°C for several months. A petroleum-derived `baby oil' was included for comparison.
Sunflower oil was applied in two seasons. Canola, castor, palm, peanut and the purified petroleum oil were used in a single season.
All oils considerably reduced scald without causing injury. Two drops of oil (approximately 25 mg) had marked effects on the severity of superficial scald. The severity of the disorder was related logarithmically to the number of drops of oil applied. The regression equation was: Scald score = 2.24 - 0.73 loge (no. of drops). However, oils were not significantly different in their effects on scald. Thus scald control by the different oils does not appear to be related to chain length of fatty acids or degree of unsaturation. A physical effect may be responsible for the control of superficial scald by the six oils.
Apples treated with castor or palm oil remained greasy even after storage for several months. The other oils were far less greasy and when applied in low doses there were little observable differences in greasiness compared to the controls. Canola, peanut and sunflower oils appear to have possibilities as commercial scald control agents. Baby oil would probably be unacceptable due to its petroleum origin.