Revision of Methodology Used for Determination of Vitamin A and Beta-carotene in Food

The Science Branch of the Canadian Food Inspection Agency (CFIA) has completed an evaluation of the methodology used in our laboratories to determine the Vitamin A content of foods, sports nutrition products, nutrition supplements and other food products. This study uncovered a deficiency in the method used by the CFIA when it is applied to certain products fortified with micro-encapsulated forms of ß-carotene (beta-carotene), which leads to an underestimation of the beta-carotene content. The CFIA will therefore be using two methods to determine Vitamin A content in future.

For the purposes of the Food and Drug Regulations, the Vitamin A content of a food is determined " in terms of the content of retinol and its derivatives and beta-carotene, expressed as retinol equivalents (RE)" . In other words, to determine the total Vitamin A content it is necessary to determine the amounts of the different compounds that can contribute to the total amount of Vitamin A, including beta-carotene.

Beta-carotene can be added to food products in different ways, including oil suspension and micro-encapsulation. There can be several different types of micro-encapsulation materials or methods.

The CFIA's evaluation showed that the Agency's method for determining Vitamin A, which detects both retinol and beta-carotene, is valid for retinol-based forms of Vitamin A and for oil suspensions of beta-carotene, but that it underestimates micro-encapsulated forms of beta-carotene.

The CFIA's Science Branch has therefore determined that two different methods will be needed to detect all forms of Vitamin A: one to measure retinol-based forms of Vitamin A (the method currently used), and one to measure all forms of beta-carotene.

Many of the methods used by CFIA laboratories, including the method used to determine Vitamin A, are based on the " Official Methods of Analysis of AOAC International" . The AOAC is an international body which fosters communities of analytical scientists who work together to develop and validate the best and most needed analytical methods. AOAC methods are collaboratively studied, widely used and recognized internationally.

The method that the CFIA will now use to determine beta-carotene content (AOAC e-Cam 305) was collaboratively studied under AOAC International protocol. This new method is applicable to all forms of beta-carotene.

The CFIA is committed to using the best methodology available. We recognize that, as food technology and manufacturing techniques advance, our analytical methods may need to change in order to remain appropriate.

Originally issued December 20, 2005 (Information Letter To Industry)