Herbs are not only playing an important role due to their culinary use in our kitchens, but also as a health supplement and, more increasingly, as a natural alternative to "conventional" (synthetic) drugs. So far scientists isolated approximately 12,000 compounds which are proven to have a stimulating or healing effects on the human body, and it is estimated that this number is only 10 % of the total number of active compounds provided by nature.
While herbs for culinary use are usually processed freshly, herbs used as a health supplement or for medical applications often need to undergo a drying process, either to conserve their active ingredients, to protect them from spoilage due to micro-organisms, moulds or pests, or to prepare them for further processing, i.e. to grind them into powders, or to turn them into balms, creams or tinctures. However, because the active ingredients, e.g. alkaloids, proteins etc, are usually sensitive to excessive heat, herbs can only be dried at modest temperatures. This makes conventional drying methods not only time and space consuming, but also increases the risk of spoilage.
A faster, safer, more efficient and more gentle method of drying herbs is the use of microwave vacuum dryers. The herbs are put on trays and placed into an airtight vacuum chamber, which is then evacuated. Once the required vacuum is reached, the herbs are exposed to microwave energy, which heats up and evaporates the water contained in the herbs. Because the boiling temperature of water is a direct function of the ambient pressure, the actual temperature the herbs are exposed to can be easily controlled by adjusting the vacuum pressure. Careful design of the microwave distribution system and electronic control of vacuum pressure and reflected energy guarantee an even and gentle drying process, the system is also capable of determining the end of the drying process, thus preventing over-drying. Because water evaporation consumes a considerable amount of energy, we also offer a energy recovery system as option, the recovered energy can then be used to heat up water required for other processes like washing, heating etc.
Should you require any further information regarding the above application please contact us.