92 Handbook of herbs and spices
Ginger
Ginger oil is produced by steam distillation of the freshly ground ginger. The ginger
oleoresin contains the volatile oil and the pungent extracts. The oleoresin can be
encapsulated to present it in a dried form. This can be achieved by spray drying and
can then be easily incorporated in food products.
Cinnamon
Cinnamon bark produces two oils, a superior type derived from the inner bark and a
lower quality from broken quills, chips and bark. Cinnnamon oil is frequently sold as
unrefined crude oil in 200-litre drums, or refined in 50-litre and 200-litre drums. The
oils should be kept cool and should be stored in containers that have the minimum
allowable oxygen headspace to minimize oxidation and loss of product quality.
Turmeric
Turmeric is an important spice which is used in curries and as a natural colouring.
Among the cuciminoid pigments responsible for the colour of turmeric, curcumin is
a major pigment. The curcumin content continued to decrease during storage up to a
period of ten months and after this period the level of decrease was minor.
Nutmeg
Nutmeg oil is mainly used as flavouring in a range of edible food products and must
be stored in opaque containers and in a cool environment to protect the product from
oxidation.
Mustard
Mustard oil is obtained by extracting whole seeds to obtain an oil content of 25–35%
and is mainly used as cooking oil. To maintain the product quality it should be
packaged in opaque glass or high-protection barrier plastic to prevent oxidation and
maintain quality.
5.5 Oleoresins.......................................................................................
Spice oleoresins are a liquid, semi-solid or solid residue obtained by solvent extraction
and possessing the full character of natural spices. The main components of an
oleoresin include essential oils, fixed oils, pigments, pungent constituents and natural
antioxidants. The process for obtaining oleoresins is designed around extracting both
essential oil and non-volatile components that are desirable and contribute largely to
the flavour profile. The solvent is removed by using a vacuum and the concentrated
extract is the oleoresin. The physical characteristics of oleoresins range from viscous
oils to thick, tacky pastes. This makes it difficult to add these components directly to
the food. The most suitable method for utilizing the oleoresins is to use a carrier and
options that are utilized are as follows:
∑ emulsions prepared by blending essential oils with gum arabic or other
emulsification agents
∑ essences developed with ground spices and ethanol and the addition of essential
oils or oleoresins
∑ solubilized spices are blended with essential oils and/or oleoresins mixed with a
polysorbate ester or other agent