Skim milk powder is obtained by removing water from pasteurized skim milk. It contains 5% or less moisture (by weight) and 1.5% or less milk fat (by weight). By removing moisture to the greatest extent possible, microbial growth is prevented. Skim Milk powder is classified for use as an ingredient according to the heat treatment used in its manufacture. There are three main classifications: high-heat (least soluble), medium-heat, and low-heat (most soluble). Skim milk powders are available in spray-dried form. Spray-dried skim milk powder is available in two forms: ordinary or non-agglomerated (non-instant) and agglomerated (instant).