Pineapple
The pineapple is an acid, tropical fruit with yellow fruit flesh.
Ripening instructions
Very often you will get unripe fruits. You can let them rest on your counter to ripen them.
Always store your pineapple upside down, this ensures that it will ripen evenly as the ripening agents tend to settle to the bottom (thank you for the advice, Marina).
Ripening indicators
There is no such thing as the "perfectly" ripe pineapple. The pineapple is ripening bottom to top, so very often it will be overripe at the bottom and still unripe at the top. You have to decide for yourself when the best time comes to cut your fruit. If it starts to smell like pineapple it is getting ripe. An other indicator is when you can pull out its leaves easily.
Season
You get them especially in winter.
Wikipedia
Pineapple on Wikipedia
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