31-10-2014, 03:49 PM
Understanding Biocolour- A Review
1407992213-UnderstandingBiocolourAReview.pdf (Size: 203.2 KB / Downloads: 74)
Introduction:
The colour of food is an integral part of our culture and
enjoyment of life. They have been used to enhance the
aesthetic value of foods. Colour is the most important
characteristic of food, since common consumers usually
judge quality of the food from its colour. Overall objective
for the addition of colour in food is to make the food more
appealing and recognizable. Everyone is sensitive to the
colour of the food as it can stimulate or suppress one’s
appetite. There are several reasons for the addition of
colours to food as mentioned below:
1. To make up the colour loss due to light, air,
temperature, moisture and storage
2. To correct natural variations in colour
3. To enhance the natural colours associated with a
given product.
4. To provide a colourful identity to the colourless or
dull looking foods.
5. To provide a colourful appearance to foods.
6. To protect flavors and vitamins that may be
affected by sunlight.
In the decade of sixty, synthetic colours such as azo dyes
became highly popular owing to their low cost and easy
availability. However subsequent toxicological evidences
and adverse physiological effects of many such synthetic
food colours has resulted in their removal from the
permitted colour list for food uses and even more are likely
to be banned in near future. Some of them were found to be
carcinogenic.
What is Biocolour?
BIOCOLOUR word consists of two words BIO meaning
natural & COLOUR meaning anything which is used for
colouring purpose. Bicolour is any dye obtained from any
vegetable, animal or mineral, that is capable of colouring
food, drugs, cosmetics or any part of human body. These
natural colours come from variety of sources such as
seeds, fruits and vegetables, leaves, algae & insects.
According to the application a suitable Natural Colour can
be achieved by keeping in mind the factors such as pH,
heat, light, storage conditions and interaction with other
ingredients of the formula or recipe. The storage conditions
for natural colours depend on the particular need of the
product. A tight sealed container is best to store the product
in a cool storage to preserve colour strength and quality,
along with its degree of cooling point. As per FDA colour
pigments having a natural origin are exempt from
certification. It does not carry any categorization as natural
or synthetic. The reason is that the source may be natural
but it may or may not be natural to the food it is added to.
There are 26 colours permitted to be used in food and 28 to
be used in cosmetics and pharmaceuticals. A few
commonly used natural colours are Annatto (seed),
turmeric, beet juice (root), bell pepper, red cabbage
(vegetable), spinach (leaf) etc. Table 1 shows the colour
shade and EEC No. of the biocolours.
History of Biocolours:
Colour is vital constituent of our food. Colour irrespective
the form has been added to our foods from centuries. The
colouring of candy by the Egyptians and colouring of wine
dates bake to as long ago as 400 BC. Saffron, turmeric and
paprika etc were used as traditional food colourants. Butter
has been coloured yellow as far back as the 1300s. The
use of colourants in cosmetics can be traced to the early
Egyptian transcripts. In nineteenth century, synthetic
organic dyes were developed creating, a more economical
and wider range of colourants. Since then their quality has
been improved due extensive research and development.
Ancient Romans used saffron and other spices to put a rich
yellow colour into various foods. Other natural foods, such
as carrots, pomegranates, grapes, mulberries, spinach,
beets, parsley and flowers, were also used as food
colouring agents. Our ancestors also used minerals and
ores, such as azure (copper carbonate), gold and silver
leaf, some of which were downright poisonous if used
improperly. Elise Fleming researched cookbooks dating as
far back as 1390 A.D. In the late 1800’s the food industry
had a vast array of available synthetic colours. After the
discovery of Perkins mauve named after the developer Sir
Williams Henry Perker in 1856 many new colour were
synthesized. These were called coal tar colours as the
starting material was obtained from bituminous coal.
Chemically synthesized colours were used extensively as
they were
Why Should Industry Use Biocolours?
With the advent of strict legislative regulations and growing
awareness among the consumers about food safety,
bicolour have become the choice in the foods as they are
extracted from sources of biological origin and are much
safer than their synthetic counterparts. Biocolour could be a
dye, pigment or substance that can impart colour when
added or applied to a food drug, cosmetic or human body
but is of biological origin derived from plants, insects or
microbes. There are a number of natural colours, but only
few are available in a sufficient quantity to be useful for the
industry because they are directly extracted from plant,
flowers, fruits, leaves and roots. It is therefore
advantageous to produce natural colours from different
methods. The trend towards natural foods has led in recent
years to the substitution of synthetic by natural or nature
identical colours in many foods. Table 2 shows the salient
features of some important biocolours.