Kefir (proununced ke-fear) is a new-ish product found in the supermarket chiller cabinet near yogurt and other dairy products. It has been tucked in with butter and yogurt at most health food stores for years and actually dates to 1885 in Russia, way before refrigeration. Adding kefir grains to milk is what produces kefir. The grains are composed of lactic acid bacteria, yeast and polysaccharides. The grains culture the milk, infusing it with healthy organisms or probiotics. The result is a tangy, slightly effervescent drink similar to yogurt.
Can you guess what the most-consumed fermented food is? Yogurt. Fermented from milk and live bacterial culture (like the probiotic acidophilus), yogurt is well tolerated by those sensitive to most dairy products, especially lactose. Lactose is used or eaten up by the bacteria as it proliferates and turns to yogurt. Some yogurts tout their health benefits better than others. When I read the ingredients of some brands, the list seems way too long for a product that is made from milk and bacteria.