Essential oils
Practical Action
Spice
Maximum final moisture
content % (wet basis)
Mace
6.0
Nutmeg, cloves
8.0
Turmeric, coriander
9.0
Cinnamon
11.0
Pepper, pimento, chillies, ginger
12.0
Cardamom
13.0
Table 2: moisture contents for various spices
Distillation
This section examines the three common methods of distilling essential oils first examining the
stills used and then condensers and oil separation methods.
Water distillation is the simplest and cheapest distillation method. Two stills are shown in
Figure 1 below.
The plant material is totally immersed in water and
boiled. The steam and oil vapour is condensed and
the oil is separated from the water using the system
described below. The stills used are simple and find
wide use amongst smallholder farmers, They are often
heated over an open fire, which if not carefully
controlled, may result in local overheating and
Hose to carry vapour to the condenser
(not connected)
This small still has a combined condenser on the
top of it, shown in section. Cold water is put
into the open pan and condensation collects in
the dome.
Firebox
Figure 1: Simple water stills
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