Dairy Unit Operations

A milk sample has freezing point $T_f = -0.405^\circ\text{C}$ compared to genuine milk freezing point $T_0 = -0.540^\circ\text{C}$. The estimated percentage of added water $W = \frac{T_0 - T_f}{T_0} \times 100 = \frac{0.540 - 0.405}{0.540} \times 100 = \frac{0.135}{0.540} \times 100$ is: