Question
I was reading the information posted on the UC Davis Postharvest web site regarding storage of Fuyu Persimmons and had some questions about the information. The text stated that optimum storage temp. is 32F with advanced breakdown between 36F and 56F. Our farm cooler is kept at 34F with a lot of other ethylene producing fruit in storage as well. Last year it seemed like the fruit that remained on the trees, exposed to seasonal temp fluctuations, remained firmer longer than fruit in storage. I had one buyer who didn't want to purchase the fruit because it was being stored at 34F, which according to your information would be near perfect storage temp. Any thoughts? (L.M.O.)
Answer
Fuyu persimmons produce very little ethylene of their own, but are very sensitive to ethylene action even at 32-34F. Thus, in addition to cooling and storage at 32-34F, they should be protected from sources of ethylene, such as apples and other fruits. If you are unable to separate Fuyu persimmon from all ethylene-producing fruits, you may want to consider packaging the Fuyu persimmons in plastic box liners or bags that will modify the atmosphere around them to 3-5% oxygen and 5-8% carbon dioxide (balance nitrogen). Modified atmosphere packaging inhibits ethylene action on fruit softening and is an effective supplement to maintaining optimal fruit temperature (32-34F).
-Adel Kader