Not to be confused with vitamin C, citric acid is a sour-tasting, naturally occurring compound present in a variety of fruits, particularly those in the citrus family, such as lemons, limes and oranges. It is also available as a white crystalline powder extract of these fruit juices. Citric acid is primarily used as a flavoring or firming agent in foods and beverages, although it may be in anything from medications to beauty products. In some cases, this compound also acts as a preservative. Cooking with citric acid is relatively simple.
Add 2 tbsp. of bottled lemon juice or ½ tsp. of powdered citric acid for every quart of tomatoes you are canning. Citric acid will help keep the tomatoes firm while reducing the overall pH level to prevent spoilage.
Sprinkle 1 tbsp. of fresh lemon juice or 1 tsp. of citric acid powder over cut or peeled fruits prior to canning. Citric acid helps prevent the oxidation and brown discoloration of susceptible fruits, such as apples and pears.
Spray a solution of 1 ounce of citric acid powder and 1 quart of water on fresh game meat prior to cooking. This helps eliminate any microorganisms or bacterial infestations. You can add a dash of citric acid for flavor while the meat is cooking.
Squeeze a lemon wedge into a thickening cheese sauce to smooth out the texture. The citric acid in the lemon juice helps inhibit the function of casein, a naturally occurring milk protein in cheese and other milk-based products, which is responsible for the thickening.
Juice lemons and limes as a marinade base for seafood ceviche. The citric acid in these fruits causes the protein in the fish or seafood to denature, giving it an opaque appearance similar to that of cooked flesh. Marinating fish such as tuna, mahi mahi, flounder and scallops takes 15 to 50 minutes, depending on the amount of the marinade. Generally, 32 ounces of seafood requires three to five lemons and limes.
Use citric acid as a salt alternative when baking breads that require a sour taste, such as sourdough and rye. Generally, recipes will not call for more than 1 tbsp.
Never use citric acid in place of proper cooking methods. If you're making ceviche, only purchase fresh seafood intended for raw consumption.