At the crime scene many thoughts go through an investigators mind. One is the
presence of a deep red liquid. Although, not always is this deep red liquid
blood causing investigators to turn to the Kastle-Meyer Colour test for
confirmation. Blood hemoglobin contains enzymes that accelerate the oxidation
of some organic compounds by peroxide called peroxidases. When hydrogen
proxide is mixed together with blood, the blood will turn a deep oink colour.
Although this does not just pick up blood, it can pick up the presence of
potatoes and horseradish, must more often than not, potatoes and horseradish
do not come in the form of a deep red liquid. A filter paper can also be use to
rub on a surface which has already been "cleaned" of blood and by adding a
drop of hydrogen peroxide and phenolphthalein produce the same pink colour
the Kastle-Meyer test will provide.