20 Brilliant Ways to Repurpose Old, Spoiled Milk

3. Use as a descaling agent

Similar to how sour milk cuts through corrosion in jewelry, it also helps loosen and remove calcified buildup. The chalky deposits found on faucets, sinks, and bathtubs can fade within a matter of moments after introducing spoiled milk. The more foul the milk, the better it’ll descale your tiles and metal faucets. Just pour some of the chunky milk on the chalky buildup and scrub vigorously with an abrasive sponge.