Butter stabilization by plant phenolic antioxidants

The aim of the study was to evaluate the effect of natural polyphenolic antioxidants isolated from the roots of skullcap (Scutellaria baicalensis Georgi) and procyanidins extracted from the bark of hawthorn (Crataegus oxyacantha) on butter during storage. Alpha-Tocopherol, beta-carotene, fatty acids and cholesterol contents were analysed in butter stored for 28 days at a temperature of 4 and 30 deg C in darkness as well as at 50 deg C with light (3600-3900 lx). Moreover, an increase in peroxide value was measured using thiocyanate method and the content of secondary oxidation products was analysed during storage with the thiobarbituric reactive substances (TBARS) methods. The highest increase in peroxide value and content of secondary oxidation products was observed for samples exposed to light and temperature. The flavones isolated from skullcap roots were characterized by significantly stronger antioxidant and photoprotection activity than procyanidins extracted from hawthorn bark. In butter samples with skullcap flavones added, the contents of alpha-tocopherol and beta-carotene, polyunsaturated fatty acids and cholesterol were higher than in control samples, despite the storage conditions. Moreover, ground skullcap roots incorporated in the butter showed antioxidant activity as compared to a highly purified commercial preparation of skullcap