Question
I have a question regarding chilling injury in whole fresh pineapples. The
Vazhakkulam Variety of Pineapple, grown in India, shows Chill Injury i.e. formation of brown spots/ ring around the centre stem of the fruit when stored at 7-10 °C, 85-90% RH and 10-13 °C, 85-90% RH for a storage period of beyond 10 -14 days.
We conducted various storage trials and observations were :
1) Chill Injury was persistent up to Storage Temperature of 17 °C, 85-90% RH for a storage period of beyond 10-14 days.
2) There was no Chill Injury at Storage Temperature of 19 °C, 85-90% RH for storage period of beyond 14 days. But, entire skin of fruit turned yellow, crown leaves started drooping, fruit pulp was dark yellow in color, soft, loose, lacked firmness, very sweet (TSS: > 18 ° Brix) and loss of flavor.
Do you have any recommendations to overcome this problem? (A.J.)
Answer
Research conducted at the University of Hawaii indicated that waxing the pineapple (not including the crown leaves) to create an internal carbon dioxide concentration between 5 and 8% reduces incidence and severity of chilling injury (endogenous brown spot) in pineapples shipped at 8 to 10 °C (Paull and Rohrbach, 1985; Rohrbach and Paull, 1982). Heat treatment (38 °C air for 24 hours) has also been shown to be effective in reducing this physiological disorder (Akamine, 1976). You may want to test the efficacy of these two treatments in reducing chilling injury of the pineapple variety that you have in your region.
Additional references
Akamine, E.K. 1976. Postharvest control of endogenous brown spot in fresh Australian pineapples with heat. HortScience 11:586-588.
Paull, R.E. and K.G. Rohrbach. 1985. Symptom development of chilling injury in pineapple fruit. J. Amer. Soc. Hort. Sci. 110:100-105.
Rohrbach, K.G. and R. E. Paull. 1982. Incidence and severity of chilling induced browning of waxed ‘Smooth Cayenne’ pineapple. J. Amer. Soc. Hort. Sci. 107:453-457.
--Adel Kader