Determination of FODMAP contents of common wheat and rye breads and the effects of processing on the final contents

The benefits of a diet, low in fermentable oligo-, di- and monosaccharides and polyols (FODMAP) for patients suffering from irritable bowel syndrome (IBS) has been well established. Thus, the exact knowledge of the amount and composition of FODMAPs in foods is of vital importance for these patients. This study investigated the possibilities of FODMAP reduction by adjusting the processing parameters, which are feasible in practise, while still producing marketable breads. Therefore, the impact of prolonged proofing and the addition of sourdough on the FODMAPs in the final products was evaluated. High performance anion exchange chromatography was used for qualitative and quantitative analysis. A prolonged proofing time resulted in reduction of the fructan content and in consequence of the total FODMAPs. In contrast, the addition of sourdough only altered the FODMAP composition, by reducing the fructan content but increasing the mannitol content. While all the breads produced from refined wheat flour meet the low-FODMAP criteria, the breads from rye and whole meal wheat flour have to be considered as high-FODMAP, regardless of the processing conditions investigated. Breads produced from rye flour exceeded the limits for fructans and mannitol, while whole meal wheat breads were found to exceed the threshold for excess fructose. Overall, the production of low-FODMAP rye breads was identified as the biggest challenge for future research, since it could not be achieved using conventional processing parameter.