The primary purpose of any marinade is to add flavor. Many marinades also have a secondary purpose, which is to break down connective tissue in meats to make them more tender. The acidic ingredients found in vinegar, beer, wine, and some other foods are necessary to the tenderizing process. The soy sauce in a soy sauce marinade also fulfills this function.
Soy sauce marinades suffuse a wide range of meats and veggies with dark, mysterious flavor reminiscent of Asian cooking. Beef, chicken, and pork all benefit with a marinade soaking of several hours, while shellfish, seafood, and nonmeat substitutes such as tofu or tempeh require much less time. A good soy sauce marinade can be as simple as soy sauce, a little oil, and perhaps some garlic, but many creative cooks experiment with a wide range of other ingredients to add dimension.
A squirt of lemon, lime, or orange juice is one popular addition. Citrus brings a high note to match the darker tone of the soy sauce. This type of soy sauce marinade is especially good with fish steaks or filets, as well as shellfish. Fish has little connective tissue, so it’s important not to let it spend excessive time in the swim as that will actually cook the flesh and turn it mushy.
Red meat and pork can stand up to an intensely flavored soy sauce marinade. Heat from mustard, horseradish, or hot sauce adds fire. Finely minced ginger and garlic and perhaps a splash of wine or sherry is another option. Some cooks find that ketchup or even diced tomatoes deepen the flavor, and others opt to add steak sauce or liquid smoke.
A popular chicken marinade requires few ingredients. In addition to the soy sauce and oil, some minced ginger and garlic add depth, and a squeeze of lemon or lime supplies some additional flavor. Just a few drops of sesame oil give this marinade a wonderful taste twist. To intensify the Asian theme, a little five-spice powder works nicely. Alternatively, a little curry powder or paste adds zip.
Marinades aren’t limited to meat. Tofu, tempeh, seiten, and other vegetarian proteins take on soy sauce marinade beautifully. These kinds of foods don’t require tenderizing, so 20 minutes or so is sufficient time to add flavor. Even some vegetables respond to marinating. Mushrooms, carrots, and root vegetables like parsnips or turnips are good candidates. As with fish and vegetarian nonmeat substitutes, a soaking of just a few minutes is time enough.