What is the percentage of water present in milk?

Milk is one of the most complete natural foods, providing essential nutrients for growth and health. The percentage of water present in milk is about 87%, which means nearly nine-tenths of milk is water. This large water content makes milk a liquid food that can easily be digested and absorbed by the body. The remaining 13% consists of important substances such as fats, proteins, carbohydrates, vitamins, and minerals.

The main components of milk include lactose (milk sugar), casein and whey proteins, milk fat, and minerals like calcium and phosphorus. Water acts as a solvent for these nutrients, allowing them to remain evenly distributed throughout the liquid. This is why milk looks uniform and smooth in texture. The high water content also helps maintain the fluid balance and supports the transport of nutrients in the body when consumed.

The exact water percentage can vary slightly depending on the type of animal. For example, cow’s milk contains about 86–88% water, buffalo milk around 82–84%, and human milk about 88–90%. Despite these differences, water always remains the largest component of milk across all species.

Water in milk also plays a crucial role in its physical properties such as density, viscosity, and freezing point. When milk is processed into products like butter, cheese, or powdered milk, much of this water is removed, concentrating the remaining nutrients.

Understanding the composition of milk is essential in both biology and food science. It helps explain why milk is an excellent source of hydration, energy, and nutrients. The balance between water and solids in milk makes it one of the most nutritious natural beverages, vital for humans from infancy through adulthood.