|
| Name
of Food Article |
Adulterant |
Simple Method for detection of Common Adulterants |
Remarks |
|
| i.
Whole spices |
Dirt,
dust, straw, insect, damaged seeds, other seeds, rodent hair and excreta. |
These
can be examined visually. |
|
| a.Black
pepper |
Papaya
seeds |
Papaya
seeds can be separated out from pepper as they are shrunken, oval in shape and greenish
brown or brownish black in colour. |
|
| |
Light
black pepper |
Float
the sample of black pepper in alcohol (rectified spirit). The mature black pepper beries
sink while the papaya seeds and light black pepper float. |
|
| |
Coated
with mineral oil |
Black
pepper coated with mineral oil gives Kerosene like smell. |
|
| b.Cloves |
Volatile
oil extracted (exhausted cloves) |
Exhausted
cloves can be identified by its small size and shrunken appearance. The characteristic
pungent tests of genuine cloves is less pronounced in exhausted cloves. |
|
| c.
Mustard seed |
Argemone
seed |
Mustard
seeds have a smooth surface. the argemone seed have grainy and rough surface and are black
and hence can be separated out by close examination. When Mustard seed is pressed inside
it is yellow while for argemone seed it is white. |
Use
magnifying glass for identification. |
| ii.Powdered
spices |
Added
starch
Common Salt |
Add
a few drops of tincture of lodine or lodine solution. Indication of blue colour shows the
presence of starch.
Taste for addition of common salt. |
Iodine
test for added starch is not applicable for turmeric powder. |
| a.
Turmeric powder |
Coloured
saw dust
Chalk powder or yellow soap stone powder |
Take
a tea spoon full of turmeric powder in a test tube. Ad a few drops of concentrated
Hydrochloric acid. Instant appearance of pink colour which disappears on dilution with
water shows the presence of turmeric. If the colour persists, metanil yellow (an
artificial colour) a non-permitted coal tar colour is present.
Take a small quantity of turmeric powder in a test tube containing small quantity of
water. Add a few drops of concentrated Hydrochloric acid, effervescence (give off bubbles)
will indicate the presence of chalk or yellow soap stone powder. |
This
test is only for Metanil yellow. |
| b.
Chillies powder |
Brick
Powder, salt powder or talc powder.
Water soluble coal tar colour |
Take
a tea spoon full of chillies powder in a glass of water. Coloured water extract will show
the presence of articficial colour. Any grittingess that may be felt on rubbing the
sediment at the bottom of glass confirms the presence of brick powder/sand, soapy and
smooth touch of the white residue at the bottom indicates the presence of soap stone.
Water soluble artificial colour can be detected by sprinkling s small quantity of chillies
or turmeric powder on the surface of water contained in a glass tumbler. The water soluble
colour will immediately start descending in colour streaks. |
This
test is only for earthy material. |
| |
Oil
solube coat tar colour |
Take
2 gms of the samples in a test tube, add few ml of solvent ether and shake, Decant ether
layer into a test tube containing 2ml of dilute Hydrochloric acid (1 ml HCl plus 1ml of
water). Shake it, the lower acid layer wil be coloured distinct pink to red indicating
presence of oil soluble colour. |
See
also Appendix-I. |
| iii.
Hing |
Soap
stone or other earthy matter |
Shake
little portion of the sample with water and allow to settle. Soap stone or other earthy
matter will settle down at the bottom. |
In
compounded hing due to presence of starch, a slight turbid solution, may be produced.
However, this will settle down after keeping. |
| iv.
Saffron |
Dried
tendrils of maize cob |
Genuine
saffron will not break easily like artificial. Artificial |
|
