Q: I was making a gelatin salad and I wanted to throw in some fruit. But isnt there some reason you cant fresh fruit in gelatin?
A: Good memory: You dont see it come up often anymore because congealed salads have fallen out of fashion. (You think it had something to do with the name?)
However, what youre remembering is the rule about not using pineapple with gelatin. It has an enzyme, bromelain, that breaks down the collagen that makes gelatin gel, turning it into fruit-colored soup.
Pineapple isnt the only fruit with the problem: Kiwifruit, papaya, mango and guava have a similar enzyme, papain.
Heating the fruit destroys the enzyme and stops the problem. So canned pineapple and mango, which are heat-processed, will work in gelatin. You can heat the other fruit, too, although heating would change the flavor and texture of delicate tropical fruit like kiwi or guava.
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