In principle, cappuccino powder is used like coffee whitener to "whiten" coffee but with the main purpose of getting a thick, stable foam layer on the surface of the coffee after reconstitution. A lot of cappuccino powder sold is already mixed with instant soluble coffee and sugar, ready to use.
The foaming ability
The foaming ability is achieved when the powder releases the gasses entrained in the powder in form of:
- Occluded gas in form of air and CO2; the latter has by purpose been injected into the concen-trate prior to drying
- Interstitial air, due to the agglomeration of the product.
The composition of cappuccino powder
The composition of the concentrate is slightly different from that of coffee whitener to enhance the ability to form a thick layer of stable foam. The typical composition is as follows:
- Glucose syrup or maltodextrine with a DE of 25-30: 40-45 %
- Vegetable fat with melting point 35-40 C: 20-25 %
- Low-Heat skim milk powder: 30-35 %
- Artificial cream flavor, color and emulsifier: 1-3 %
- Phosphates: 1-3 %
The mixing of raw material for cappuccino powder
During the mixing of the ingredients at 60-65 C to a total solids content of 50-55 % it is important to avoid incorporation of air into the concentrate, as it will take up "space" for CO2 - therefore the mixing should be done under vacuum.
After mixing, the concentrate is homogenized in two stages at 150/50 bar g followed by a pasteu-rization to 70-75 °C for 15 seconds. Then it is cooled to 50-55 °C. The amount of liquid CO2 that can be dissolved in the concentrate depends on the temperature and pressure of the concentrate. Low temperature and high pressure results in more dissolved CO2.
Drying of the concentrate is done in a Multi-Stage Dryer MSD™
as this plant offers the best possibility for agglomeration to increase the content of interstitial air. The bulk density of the final powder is typically 0.15 g/ccm; the foam height is approximately 10 mm with a stability of ½-1 hour.