Do you know What is Yakult and Frozen Yogurt. If you are looking for the definition of Yakult and Frozen Yogurt or want to know what is Yakult and Frozen Yogurt?, then this is where you will fetch your answers. Well, in simple terms Yakult is a probiotic dairy product made by fermenting a mixture of skimmed milk with a special strain of the bacterium Lactobacillus casei Shirota. While