Of the foods that contain probiotics, people are most familiar with yogurt. Yogurt can be found in flavors from chocolate to vanilla to cherry. All yogurt produced in the United States must contain Lactobacillus bulgaricus and Streptococcus thermophilus. Some yogurt brands also add other strains including Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus reuteri and bifidus. But not all foods that contain probiotics are made the same. Some pasteurize their yogurt after the bacteria are added. This kills them off. But, they must be alive for them to do you any good. Check the label to see if it says "live and active" cultures. As foods that contain probiotics age, the amount of bacteria lessens. So the fresher the yogurt is the better. Some brands of frozen yogurt also contain probiotics, but many do not.

Another one of the probiotic foods is kefir. Kefir is a fermented, probiotic-containing beverage usually made from cow, goat, or sheep milk. It can be made with soy, rice or coconut milk as well. The milk is mixed with kefir (Lactobacillus kefiri) and other species of good bacteria. The solution is finally mixed with various types of yeast. This mixture is stored at a temperature that allows the bacteria to culture the milk. It leaves it thickened and slightly bubbly. The mixture is strained and sold as a thick beverage in different flavors. These foods that contain probiotics are more preferred in ethnic markets.

Other probiotic foods include various cultured dairy products. Cultured butter milk is a common source found in most grocery stores. While not usually drank, it is used commonly in baking. Acidophilus milk is any form of milk that has been mixed with Lactobacillus acidophilus and allowed to ferment. Some organic producers of foods that contain probiotics in the United States have started introducing probiotic forms of sour cream and cottage cheese. Around the world, there are other cultured dairy foods that contain probiotics. This includes lebne from the Middle East and kermavilli from Finland.

More probiotic foods can be found out of the dairy aisle. Probiotic rich fruit-juice based drinks have been introduced. Fermented cabbage is also one of the good foods that contain probiotics. This can be seen in many popular dishes such as sauerkraut, kimchi, cortido and courcroute. Salted gherkins and brine-cured olives are also foods that contain probiotics. They must be made in the traditional way and they also contain good strains of lactobacilli. But many commercial versions of all of these products are pasteurized after packaging, which kills the good bacteria. Various brand name cereal and grain bars have been introduced that are also probiotic foods.