Answer: True
Kastle meyer test also known as phenophthalein test. It is a presumptive test for identification of blood. The reagent gives a magenta or pink color in the presence of blood. It reacts with the hemoglobin component of the blood, to develop a magenta or pink color. This test is not conclusive as a presumptive test alone but should be confirmed by performing other tests like benzidine and O- toludine test, which can also help in identification of blood presumptively. The major drawback of this Kastle- meyer test is that it gives a false positive test with vegetables materials like juices, fibers and other. Hence, makes it's acceptance as a identification test for blood futile.