The practice of soaking food in liquid goes back to the day some long-forgotten cook noticed that storing meat in seawater postponed spoilage. Through the centuries, epicures repurposed the practice to improve flavor, and knowing some basic principles can take dishes from so-so to spectacular.
The best reasons for using marinades (MEHR-in-nayds) are flavor and succulence. Acidic elements, like juice or vinegar, weaken muscle tissue, helping meat retain moisture during cooking. Herbs and spices contribute flavor. Adding oil helps prevent lean meats from becoming unpleasantly dry, and since most flavors are fat-soluble, oil also helps transmit the taste of companion ingredients.
Experts disagree about a marinade’s ability to tenderize and warn that if you marinate too long, acids can actually toughen meats. Pineapple, papaya and ginger contain protein-digesting enzymes, so a bath in pineapple juice does tenderize, as will lightly acidic dairy products like buttermilk and yogurt. A milk bath also tames the wild taste of game.
Marinades work mostly at the surface, hence flat cuts (or large ones cut into pieces) benefit most. Re-sealable plastic bags are perfect containers because the air can be squeezed out so that the marinade coats every surface. Marinades work fastest at room temperature, but always refrigerate if marinating more than 30 minutes. Boil used marinated for at least five minutes to eliminate bacteria, then turn them into sauces. Marinating can cut cooking time, so check frequently for doneness. On the grill, sugary marinades promote char, and oily marinades can cause flare-ups.
Here are some general guidelines:
Steak: 6-24 hours, depending on thickness and tenderness
Large roasts: 24-48 hours
Whole chicken: 24 hours
Chicken pieces: 4-6 hours - Pork Chops: 4 hours
Thin fish fillets: 30 minutes
Thick, fatty fish filets: 1 hour
—By Jo Marshall, a food writer in Deephaven, Minn.