Human beings have been using natural products since the dawn of time.
Plants growing wild in nature or cultivated as crops are still the prime
ingredients in many drugs, beverages, flavors, and cosmetics. GEA Niro's
comprehensive product range covers most of the required steps for processing
leaves, herbs, and other plant material, for example into extracts and then
further into powders or granulates.
Extraction
Extracts are generally concentrated forms of
natural substances obtained by treating crude material containing these
substances with an appropriate solvent such as water, alcohol, or another
organic solvent. This process can successfully be performed in the GEA Niro
continuous extraction plant CONTEX™.
The CONTEX™ unit operates in the counter-current extraction principle
featuring an inclined trough surrounded by heat transfer jackets for
temperature control of the process. The raw material (solids) enters the lower
end of the trough and is transported upwards by two heliocoidal conveyors. The
solids are therefore transported in a gentle spiral movement, which gives ideal
counter-current plug-flow extraction conditions.
Spray dryer/granulation
Spray drying is by
definition the transformation of feed from a fluid state into a dried form
(either powder or granulate), by spraying the feed into a hot drying
medium. Air is used in case of water and nitrogen if an organic
solvent is used.
Prior to spray drying, the extract normally needs to be concentrated and in most cases
formulated with carbohydrates as carrier and with water soluble gums in order
to form a protective en-capsulated surface film around each particle.