How to Substitute Sour Cream for Mayonnaise

Using sour cream instead of mayonnaise can lower fat content and number of calories in a dish, especially if you use low-fat or nonfat sour cream. Unlike yogurt, sour cream is traditionally made from cream. Lactic acid culture is added, which thickens the cream and gives it a sour, tangy taste. Thick, rich-tasting and a slightly tart, sour cream has a flavor combination that makes it an easy substitute for mayonnaise in many dishes, including sandwiches and cold salads.

While commercial sour cream contains 18 to 20 percent fat, it is still lower in fat than mayonnaise. A single serving of sour cream has roughly half the calories and fat content of mayonnaise. The difference is even greater if you use reduced-fat or light sour cream. Sour cream typically contains fewer additives than mayonnaise does, especially commercial mayonnaise, which requires numerous stabilizers and additives to keep the spread from breaking apart.

Sour cream can be used as is, or with other ingredients, in dressings, for salads and for sandwiches, substituting directly for mayonnaise. Add sour cream in place of mayonnaise in cream-based dressings. Dressings are diluted with vinegar, oil and sometimes water, and contain a number of seasonings. This makes the taste and texture differences between sour cream and mayonnaise virtually indiscernible. You can also use sour cream as is -- without any additives -- as a sandwich spread. Its cool creaminess adds richness and texture to a sandwich. In instances where using sour cream instead of mayonnaise affects the taste and texture of the dish — such as with potato or egg salad — adjust the seasonings to enhance taste. Keep dishes that use sour cream very cold, as the warmer it gets, the runnier the texture becomes.

Sour cream contains less fat than mayonnaise so it is slightly less rich tasting. And, despite its natural tanginess, sour cream is not as sour as some mayonnaise. The texture, as a cultured dairy product, is also slightly grainier and less thick. Because of these slight differences, you may choose to add in extra seasonings, such as apple cider vinegar or lemon juice, to increase the tang of sour cream. You can also add in beaten egg yolks to increase the richness. To preserve the taste of mayonnaise but garner some of the benefits of sour cream, substitute half the mayonnaise in a recipe with sour cream.

As an alternative to sour cream, you can also use yogurt as a substitute for mayonnaise. Greek yogurt, in particular, with its rich taste and increased thickness, is popular as it is lower in fat and more tart than sour cream. As is the case with sour cream, for yogurt -- including Greek yogurt -- the warmer it is, the runnier it becomes, which can affect the texture of some dishes, like potato salad. You can also make vegan mayonnaise, which uses apple cider vinegar and ground flax seeds to create an egg-free — and lower fat — mayonnaise.