Natural food and beverage colourings - Natural Food Additives, Ingredients and Flavourings - page 25

It is beyond the scope of this chapter to fully consider fruit and vegetable
extracts that are used for their colouring properties. Such ingredients, termed
'colouring foodstuffs' are derived from the concentration of recognised foodstuffs
without the selective extraction of the pigment. The trend towards greater use of
these ingredients in the future will be driven by moves to clean up ingredient
labels as these extracts are neither considered nor declared as colour additives.

2.2 Natural food and beverage colourings currently
used commercially
2.2.1 Curcumin
Curcumin, historically known as curcuma, is a lemon yellow pigment most
commonly used in a water-soluble form. It is obtained by solvent extraction of
turmeric, which is the cleaned, dried and ground rhizome of natural strains of
Curcuma longa L. The initial extract is oily and contains about 40% curcumin.
In order to obtain a concentrate containing 90% curcumin, the extract is purifi ed
by crystallisation. The fi nal powder is a deep orange yellow colour and
is insoluble in water. Minor amounts of oils and resins naturally occurring in
turmeric carry though into the fi nal colour, but these are generally at too low a
level to be problematic in the fi nal coloured application.
The original botanical origin of curcumin has given rise to frequent references
to the pigment as turmeric, but from a European legislative standpoint the pigment
should be labelled as curcumin. 1 Turmeric is grown across tropical areas of South
Asia and needs considerable annual rainfall to fully develop. The main area for
growth and extraction of curcumin is India and indeed it is sometimes referred to
as Indian Saffron.
Typical food applications are confectionary, coatings and seasonings, sauces,
desserts, yellow fats, ice cream and sorbets. Most applications for curcumin
require a water-soluble form and, as stated earlier, high strength curcumin powder
is insoluble in water. It is rendered water soluble by using food grade emulsifi ers
and heat. The result is a fi nal, stable solution typically 5-8% in strength. Current
labelling legislation does not require the on-pack labelling of additives within
additives, but they must be declared on the documentation that accompanies the
colour as sold to the food manufacturer and their use is controlled in European
legislation. Curcumin solutions prepared in this way give a crystal clear,
fl uorescent yellow colour. This can then be spray-dried to give a water-soluble
curcumin powder for those manufacturing processes or fi nal applications where a
powder is more appropriate. Typically curcumin powders commercially available
contain 2.5-3.5% curcumin.
For applications such as coatings, curcumin is often used in combination with
the orange pigment paprika to give the required shade. Due to the nature of the
water-soluble curcumin and paprika formulations, they are often supplied as
separate ingredients to be added individually by the food manufacturer. The
classic colour applied to yellow fats such as margarine is carotene but it is possible

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