The galactose content of lactose-free cow's milk formula is approximately how many milligrams per liter?

• A. 0 mg/L
• B. 20 mg/L
• C. 100 mg/L
• D. 1 g/L

Answer: (B)

Lactose-free cow's milk formula is made by hydrolyzing lactose into glucose and galactose, but trace galactose remains in the final product. That residual galactose is typically in the tens of milligrams per liter, around 20 mg/L, which is why this value best fits the expected range. Higher numbers like 100 mg/L or 1 g/L would indicate more galactose than is usually present, and zero mg/L isn’t accurate because hydrolysis yields galactose.