<h2>Milk Powdered | Definition</h2>

Milk powder is fresh milk which is evaporated all the water content. Nevertheless, milk powder still contains water in very small amounts, ie less than 5% (Hadiwiyoto, 1983).

Type of Milk Powder
Based on the milk is used as base material, powdered milk can be divided into:

a. Dry whole milk (full cream milk powder), a product obtained by evaporating water from fresh milk. This milk contains at least 26% fat milk and no more than 5% water

b. Dry milk or skim milk, produced by removing water and milk fat. Water content not more than 5% and fat levels are not more than 1.5%.

c. Dry butter milk, butter milk obtained from the evaporated water, a side product in the manufacture of dairy butter. When milk or cream be maintained at a certain temperature and stirring constantly, fat grains will agglomerate and form butter granules. Fraction of solid milk and water will be shipped with a wad of fat, whereas most of the fat and separate the byproduct called butter milk.

The properties of Milk Powder
Dried milk powder with a spray dryer irregularly shaped lumps which contain air cavities are small. Dried powder spray dryer with a more easily soluble in water if you have the size of 150 microns, below the size of the powder will float on the water and milk difficult to wet. Dried milk powder with a roll-drier has a serrated flake with a thickness of 15-20 microns.
Milk powder is very hygroscopic. If the humidity exceeds 25%, lactose will absorb moisture so that the milk powder becomes sticky. If the water content in the milk reached 80%, lactose will crystallize.
Requirements include powdered milk is a good solubility power, and no foreign odor (off-flavor). Solubility is affected by milk powder protein. Powdered milk protein content is strongly influenced by the nature of the warming and drying done. The form of milk protein casein and albumin are particularly vulnerable to warming at high temperatures. Temperature extremes can cause damage to proteins.

Damage of Milk Powder

Milk powder can be damaged due to poor storage conditions well. Damage that may occur include:
1. Fat Damage
a. Hydrolitic rancidity, damaged fat dikatalisa by the enzyme lipase and accelerated by the water. Rancidity more rare in milk powder by drying process roll for a high temperature in the roll-dryer has destroyed lipase enzyme activity.
b. Oxidized flavor, damage due to fat oxidation reaction with the outside air to form peroxides and aldehydes, giving rise to unpleasant smell (rancid). This damage can be prevented by packing milk powder in a vacuum or with inert gas is N2 to remove existing O2.

2. Non Fatty Compouns Damage
a. Damage to proteins that cause odor as the water content and high storage temperature.
b. The occurrence of lactose caramelize, the reaction between sugars with proteins or the outbreak of sugar into furfuraldehid and react with nitrogen gas. These things cause Browning.