Tocotrienols in three rye varietes: from the grain to the bread
2007
Zielinski, H. | Michalska, A. | Szawara-Nowak, D. | Wiczkowski, W. | Piskula, M.K.,Polish Academy of Sciences, Olsztyn (Poland). Inst. of Animal Reproduction and Food Research
In this study the contribution of tocotrienols to the total tocols of three varieties of rye grain (Amilo, Warko and Dankowskie Zlote), their morphological fractions, milling products and breads made from them was shown. Tocotrienols (alpha-T3, beta-T3, gamma-T3) and tocopherols (alpha-T, beta-T, gamma-T, delta-T) were extracted with methanol and separated by HPLC. The study showed that the richest source of tocotrienols was the whole grain of Dankowskie Zlote followed by the whole grain of Warko and Amilo cultivars. The tocotrienols found in the whole grain of three rye cultivars were alpha-T3 and beta-T3 while the pool of tocopherols was formed by alpha-T, beta-T and small quantity of gamma-T. Tocotrienols found in the whole grain or in endosperm with embryo fraction contributed to more than 50 percent of total tocols, however those noted in pericarb with testa fraction were about of 90 percent of total tocols. The highest level of tocotrienols (alpha-T3 + beta-T3) was noted in rye flours with extraction rate of 100 percent of the three cultivars. The milling process decreased contents of tocotrienols, however flours with extraction rate from 100 to 90 percent kept the T3/T ratio above one, whereas for flour with extraction rate of 70 percent this ratio was less than one. The percentage contribution of alpha-T3 and beta-T3 to the total tocols content in whole meal and brown flours was within a range of 23-35 percent but that noted for light flours was within a lower range. The baking process caused a significant decrease in the content of tocotrienols as well as tocopherols. The level of tocotrienols in whole meal rye breads was about five, three and two times higher when compared to the bread formulated on brown flours originated from Amilo, Warko and Dankowskie Zlote. Moreover, the level of tocotrienols found in breads formulated on light flour (extraction rate of 70 percent) was about 2-13 percent of that noted in breads based on whole meal flour
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