Tocopherol as a Measure of Dairy Product Adulteration

Mahon et al. (1955a, b) have used the tocopherol analysis as a clue to the detection of adulteration of dairy products with oils and fats. The 

Total Tocopherol Content of Vegetable and Animal Oils and Fats  

Kraybill (1956) observed that 10-30 % of the tocopherols in dairy products were destroyed when irradiated with 80,000 roentgens per hour. Rose et al. (1961) irradiated solutions of DL-alpha-tocopherol with a Co source and observed extensive destruction of this vitamin and a rise in products similar to those obtained by autoxidation. Irradiation in saturated solvents destroyed more tocopherol than did irradiation in unsaturated solvents (such as methyl linoleate). 

The literature relating to the effects of storage and processing on the retention of tocopherols in foods is limited, controversial, and inadequate. Most of the published data must be considered to be qualitative, or at most semiqualitative, for the methods of analysis for total tocopherols have only recently become precise. Even so, accurate data on the total tocopherol content of a food or tissue are not pertinent because the several natural tocopherols they contain differ greatly in vitamin E activity. 

Knapp and Tappel (1961) have observed that vitamin E is far more sensitive than carotene and vitamins A, D, and K when irradiated in pure solutions by y-rays, and is the only fat-soluble factor that is adversely affected by the presence of oxygen during irradiation. 

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