Question

Fresh milk has a pH of 6. When milk changes into curd, the pH value will ______.

Options

• become 7

• become less than 6

• become more than 7

• remain unchanged

Answer 1

Fresh milk has a pH of 6. When milk changes into curd, the pH value will become less than 6.

Explanation:

When fresh milk is converted into curd, Lactobacillus bacteria ferment the lactose sugar present in the milk into lactic acid. As the concentration of this acid increases, the solution becomes more acidic, which naturally lowers the pH. On the pH scale, a higher concentration of hydrogen ions yields a lower numerical value, causing the final pH of curd to drop into a typical range of 4.5 to 5.5.