Starch digestibility index and antioxidative properties of partially baked wheat-flour bakery with an addition of dietary fibre

The aim of this study was to evaluate the impact of bake-off technology with the freezing process of wheat-flour rolls, and with the inclusion of dietary fibre on the starch digestibility index and antioxidative properties. Research material consisted of four kinds of wheat rolls. These were baked conventionally and with bake-off technology, with and without the additional 10% fibre (oat fibre and inulin). The following parameters were measured: The content of the total starch (TS), slowly digestible starch (SDS), rapidly digestible starch (RDS), the starch digestion index (SDI), the content of the total polyphenols and the ability to quench the free ABTS(center dot+) radical. The freezing process and the addition of dietary fibre contributed to a significant increase of the SDS fraction, while the RDS and SDI were decreased in partially baked rolls (p < 0.05). The amount of the total polyphenols was significantly higher with the addition of fibre and the use of the freezing process, while the antioxidant activity was increased when fibre was incorporated into the conventionally baked rolls (p < 0.05). Freezing applied simultaneously to bake-off technology, and the addition of oat fibre and inulin to the dough resulted in bakery products of not only reduced starch digestibility but containing more antioxidants, which from a nutritional point of view, appears to be advantageous.