Kefir is a probiotic-rich fermented dairy item originating from the north Caucasus. Its consistency is like that of a thin yogurt, its taste is tart and it contains very little lactose due to its fermentation process.

Thanks to its live cultures, kefir can be substituted for traditional yeast in sourdough bread, and to mimic buttermilk when baking. It’s also used in smoothies and sometimes as a tangy milk alternative in cereal.

It can also be consumed on its own and often, like yogurt, it is sold in retail with varying flavors added.

In recent years, marketers of kefir have capitalized on the gut health trend, which often focuses on ingredients that contain live cultures to help diversify the microbiome.

Market research firm Datassential reports that 34% of the population knows what kefir is but only 15% have tried it.

Click through the gallery to learn more about the flavor of the week and see how one restaurant is using kefir on its menu.