My daughter is allergic to whey which is in almost every yogurt dairy type pro-biotic so I had to find as many alternative sources of pro biotic as I could. I came upon a website
http://wildfermentation.com/ Preserving your foods in this manner gives it beneficial bacterias that work as a pro-biotic. You can get your beneficial bacterias from many sources such as cabbage heads, cucumbers, green tomatoes, string beans, okra, zucchini, eggplant, peppers, and more.