A study on vitamin D and vitamin A in milk and edible oils available in the United Arab Emirates

Two high-performance liquid chromatography methods have been validated for the determination of vitamin D and vitamin A in milk and edible oils. The percentage recovery of vitamin D added to milk ranged from 89% to 105%, with the repeatability relative standard deviation ranging from 2.78% to 6.11%. Its recovery in oil samples ranged from 90% to 102%, with the repeatability relative standard deviation ranging from 3.97% to 7.54%. The average recovery of vitamin A added to milk was found to be 98.7%. Analytical data for vitamin D in different brands of milk and milk products in the market samples of the United Arab Emirates indicate that 87% of samples contain vitamin D with 39% of samples within the acceptable range (0.8-1.2 µg/100 ml), where as 31% were found to be under-fortified and 30% were over-fortified. Analytical data for vitamin D in edible oils confirm a large variation. All milk samples analyzed contain less than 55 µg/100 ml vitamin A.