EFFECT OF GRAIN PRESERVATION ON THE CAROTENOID AND TOCOPHEROL CONTENT OF CEREAL GRAINS*

The aim of this study was to determine the effects of different wet grain preservation methods on the concentrations of b-carotene, xanthophyll, a-tocopherol (a-T), b-tocopherol (b-T), g-tocopherol (g-T) and d-tocopherol (d-T). Wet oat, triticale, barley and maize grain was dried at temp. of 60 degrees C or 110 degrees C and ensiled without additives or with 0.5% addition of propionic acid (+PA) or formic acid (+FA). Dried and ensiled maize grain had a higher content of b-carotene, xanthophyll, a-T, b-T, g-T, d-T, total tocopherols and vitamin E equivalent (Vit. EEq) than dried and ensiled oat, triticale and barley grain (P50.01). In dried cereal grain, the average losses of b-carotene, xanthophyll, a-T, b-T, g-T, d-T, total tocopherols and Vit. EEq were 57, 35, 84, 65, 67, 52, 74 and 81%, respectively, compared with their concentrations in wet grain ("0"). The content of xanthophyll, total tocopherols and Vit. EEq in grain decreased with an increase in drying temperature (P50.01). In ensiled cereal grain, the average losses of b-carotene, xanthophyll, a-T, b-T, g-T, d-T, total tocopherols and Vit. EEq were 52, 30, 83 50, 78, 63, 75 and 79%, respectively. Additives +PA and +FA affected only the b-T content (P50.01) of cereal silage. Grain drying resulted in greater losses of b-carotene, xanthophyll, a-T, b-T and Vit. EEq, whereas ensiling led to greater losses of g-T, d-T and total tocopherols. Dried triticale grain was characterized by greater losses of b-carotene, a-T, d-T and total tocopherols, and ensiled oat grain was characterized by greater losses of a-T, g-T, total tocopherol and Vit. EEq relative to the corresponding samples of dried and ensiled grain of the remaining cereal species.