The clam juice available in stores is the liquid that results from straining clams. It generally includes added salt. Dishes such as clam chowder and seafood soups often include clam juice. Using a lower-sodium alternative for clam juice reduces the sodium in the recipe. Depending on the ingredients in the dish and the reason for the substitution, you have options to make a substitute for clam juice.
Fish Stock or Seafood Bullion
Substituting an equal amount of water for clam juice works well for a dish made with fish or seafood. Simmering the fish or seafood with the water will result in a fish stock that can substitute for clam juice. For a recipe that doesn't have fish or seafood, a seafood bullion cube adds flavor to substitute for clam juice. Keep the recipe's liquid content in balance by dissolving the bullion cube in part of the liquid for the recipe -- for example, heat 1 cup of milk, water or tomato juice and stir the bullion into it, counting that as 1 cup of the recipe's liquid.
For recipes that need more flavor, such as a white pasta sauce, or to make a dish for someone who has a seafood allergy, equal parts of chicken broth and water substitute for clam juice. A low-sodium chicken broth is a healthy option for cutting down on salt in the dish. Clam juice contains 120 to 280 milligrams of sodium per 1/4 cup, according to Ellen Brown, author of "$3 Low-Sodium Meals." Brown suggests using seafood stock or chicken stock for a low-sodium fish stew.
For a vegetarian version of a recipe that calls for clam juice, vegetable stock will add body and flavor. A tomato-based stock with celery gives a sweet flavor and works well a vegetarian dish or for a fish and seafood soup. Making your own vegetable stock allows you to control the flavor and ingredients. For example, portobello mushrooms add body and flavor to a roast vegetable stock made with garden vegetables, herbs, tomatoes, olive oil and dry white wine. Simmer the roasted vegetables for 45 minutes, and use a sieve to strain the mixture to make the stock, according to Epicurious.
Clam Juice Substitution
In case of seafood allergy, use water, chicken broth or vegetable stock and omit any seafood ingredients, including seafood bullion cubes. Low-sodium chicken broth offers an option if you or members in your household want to reduce sodium in your diet. Dry white wine or dry sherry work well as part of a recipe's liquid to add flavor and reduce sodium. Wine works well for poaching fish, making pasta sauces and adding to soups or stews.