HOW TO DETERMINE VITAMIN A CONTENT (COLORIMETRIC METHOD)

DETERMINATION OF VITAMIN A (COLORIMETRIC METHOD)

AIM:
To determine the vitamin A content in margarine or food sample.

APPARATUS:
Test tubes, colorimeter, pipettes.

REAGENT:
Chloroform, antimony trichloride reagent (Carr-Price reagent).

PRINCIPLE:
Vitamin A reacts with antimony trichloride to form a blue complex, measurable colorimetrically.

PROCEDURE:

• Extract sample with chloroform.

• Add 2ml of Carr-Price reagent.

• Measure absorbance at 620 nm.

• Compare with vitamin A standard.

CALCULATION:
Use standard calibration curve to estimate µg vitamin A.