Organisource brand Overstock, never opened! Natural Unflavored Collagen Peptides provide your body with unparalleled nutrition for your health, both inside and out. Sourced from farm-raised, grass-fed beef, our pure collagen proteins can help boost your natural metabolism, strengthen your body inside and out, provide the building blocks for stronger, leaner muscles, and even help reduce leaky gut syndrome. 40 calories per serving. dissolves & mixes easily.