It is a product deriving from cow’s milk and is obtained through its dehydration. This practice has been used since the 13th century. The modern method was patented in 1847.
PRODICTION TECHNIQUES
Dehydration can be carried out through two different techniques: roller-dry or spray-dry.
Roller-dry technique – Milk is poured into two heated (130°-150°C) cylinders rotating to opposite directions. In a short time water evaporates and solid deposit is collected. This technique causes protein alteration; the finished product is yellowish and tastes not so good.
Spray-dry technique – This process is based on atomization of pasteurized and homogenized milk which is sprayed through tiny nozzles forming very little drops into a very hot (150°C) chamber where moisture is made to evaporate and powder is ready.
SOLUBILITY
Milk powder can sometimes have problems with solubility. These are solved humidifying powder through spray steam and, after drying and cooling it, ready-to-use powder is obtained.
TYPE
Milk powder is available as whole, semi-skimmed or skimmed. Italian requirements establish that whole milk must have 26% fat content, semi-skimmed milk must have 13%-17% fat content and skimmedmilk must have no less than 0,5% fat content.
Milk powder must be rain-sprinkled into warm water to avoid lump forming.