Our Cow Kefir Yeast is Made in Turkey. Our Product is Made from Pure Cow's Milk. We Send Live Yeast. There is No Possibility of It Not Fermenting. You Can Ferment It With Any Kind of Milk. You Can Ferment It With 1-3 Liters of Milk, With the Amount We Send. If You Ferment Without A Break, Your Yeast Will Multiply. Kefir Must Be In A Warm Environment While Fermenting, It Should Be Waited Until It Gets The Consistency Like Boza. 24 -If your yeast does not ferment in 48 hours, you can ask us a question using the "Ask the Seller" button. We send it in a glass jar with water. We send it with a special packaging system - it does not break or spoil. Size: 4.5cm/4.5cm/5cm