Unlike pork or beef, you don't need to marinade shrimp for hours before eating. A short bath in a tasty mix of lime and spice is enough to give shrimp a delicious tang. Neither does shrimp need long on the grill. Grilled shrimp and pineapple skewers could be ready to eat in under and hour, from marinade to plate.
An acidic marinade containing vinegar or citrus will break down the shrimp. If left too long, this can make shrimp too mushy for the skewer. For example, shrimp only needs 15 minutes in a marinade of lime juice and rice wine vinegar. If you're using canned pineapple, use some of the juice in the marinade. You don't need to marinate the pineapple chunks at all before cooking. Just thread them on the skewer with the shrimp. If you leave the shrimp in their shells, then increase the marinade time to a few hours.
Mixing and Marinating
Adding a little olive oil, honey or even maple syrup can help the marinade stick to the shrimp. Thin marinades made solely from citrus juices or vinegars will penetrate the shrimp, but may not cling to the soft flesh for grilling. Olive oil creates a protective barrier that keeps the shrimp moist when cooking. Always cover and refrigerate the prawns when marinading to prevent contamination.
The Thrill of the Grill
You need a hot, almost smoking grill to cook shrimp. This will give you delicious seared lines on the shrimp and pineapple pieces. The heat means your skewers could be ready in mere minutes. For example, a BBC Food recipe suggests grilling for 3 to 4 minutes, turning half-way through the cooking time. Larger shrimp take longer to grill. Whatever the size, the shrimp are ready when the inside is firm and pink, not translucent. If using wooden skewers, wet them before cooking to prevent burning.
Marinating Shrimp Safety
With shrimp, the fresher the better. The flesh should be shiny and translucent when raw and produce no unpleasant smells. Never reuse or taste shrimp marinade after use, as it can contain nasty bacteria, according to the U.S. Food and Drug Administration. If you want to reuse a marinade, boil it up or cook thoroughly before eating. Once cooked, you can store shrimp and pineapple skewers in the refrigerator for up to two days.