Within the diploma thesis we have studied how different amounts of added germinated wheat grains (KPZ) affect the antioxidant properties of bread. First, the preparation of phenolic compounds (FS) extracts from pre-homogenized and lyophilized bread samples with 0%, 5%, 15% and 30% addition of KPZ were performed. Extractable FS were obtained from bread using methanol, while bound FS were released from the cell matrix after alkaline hydrolysis. The Folin-Ciocalteu (FC) method was used to determine FS content, and the ABTS and DPPH methods for antioxidant determination. Similar results were obtained with all three methods. Bound antioxidants predominated in bread with KPZ, regardless of their amount. A 15% addition of KPZ resulted in considerable enlargement of reactivity of extractable (1.9-fold in the FC method, 2.6-fold in ABTS method and 7.4-fold in DPPH method) and bound antioxidants (2.5-fold in the FC method and 1.6-fold in the ABTS method). Enrichment of bread with KPZ resulted in higher absolute increment of bound and higher relative increments of free antioxidants. The content of the compound with antioxidant activity did not increase in proportion to the amount of added KPZ, supplement of 30% KPZ was not justified.
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