Milk. Probiotic cultures. Perfection. Black Sheep Yogurt is now Nature's Perfect Sheep Yogurt. Nature's Perfect Superfood. Grade A. PerfectYogurt.com. Sheep naturally produce nutrient-rich whole milk that makes thick, rich, better-tasting yogurt. No thickeners. No stabilizers. Non-GMO. Non GMO Project verified. nongmoproject.org.