Quantity Analysis of Vitamin D3 in Cow's Raw Milk in Sari City in North of IRAN

Vitamins are necessary for metabolic reaction in the body and act as coenzymes. The results of different studies about the quality and quantity of fat soluble vitamins in milk showed that milk, with different percentage of lipid, has different amounts of fat soluble vitamins such as A, D and K. In this research, concentration of vitamin D3 in cow’s raw milk in Dairy Products Factory was evaluated. Sampling was done in March, April andMay 2007. Preparation of samples and HPLC set up was done as AOAC method. The results showed that Mean and Standard Error of vitamin D3 in March, April and May were 202. 6+ 56, 196.5+ 44.28 and 159.7+41.62 IU/ml respectively. However, variations of the results in three months were not significantly different (P<0.05). D3 value in this study was higher than the standard level but pasteurization process can cause decreasing of vitamin D3 in milk