Milk stain

In detail

Milk is an emulsion of butterfat in a protein solution, and both fractions matter. The fat leaves a faint greasy halo; the protein is what binds to a fibre and, more importantly, what feeds bacterial growth as it breaks down. That is why a milk spill on a carpet, a car seat or a mattress is remembered as a smell rather than as a stain: the visible mark dries almost invisible while the protein remains in the pile and putrefies. The treatment rule shared with every protein stain is that heat sets it — hot water denatures the protein and locks it into the fibre, after which nothing domestic will remove it. The carpet institute puts milk on the protein branch, opening with a solvent for the fat and then running detergent, an ammonia solution, a vinegar solution and warm water. For the odour half of the problem, an enzymatic treatment that digests the protein itself is more effective than any masking product, because the smell is being produced continuously by what is still in the material. Speed and cool water do more for a milk spill than any product choice.

Why

• Milk stain is explained by Protein denaturation
• Milk stain is explained by Adsorption of odour molecules
• Milk stain is explained by Heat-set stains
• Milk stain is explained by Penetration into fibres