Pineapple

Since pineapple won't sweeten after harvest, judge ripeness now: it should feel heavy and dense for its size, smell sweet and fragrant at the base (a sour or fermented smell means overripe), and give slightly when pressed. The skin should show a golden-yellow tinge, not be entirely green; the crown leaves should be fresh and green. Avoid soft spots, dry brown leaves, or a wet, leaky base.

A whole pineapple keeps a few days at room temperature (turning it upside down briefly can help distribute the sweetness) or up to a week in the fridge. To cut: slice off the crown and base, stand it up, and cut away the skin in strips, removing the dark 'eyes' by carving shallow diagonal grooves. Then quarter and cut out the firm central core. Refrigerate cut pineapple in a sealed container for a few days.

Fresh pineapple contains bromelain, a protein-digesting enzyme that tenderizes meat (great for marinades) but also prevents gelatin from setting, so jellies and panna cotta won't firm up with fresh pineapple — cook or use canned pineapple (heat deactivates bromelain) instead. Bromelain is also why eating a lot of fresh pineapple can make your mouth tingle or feel raw.