Investigation of different dietary-fibre-ingredients for the design of a fibre enriched bread formulation low in FODMAPs based on wheat starch and vital gluten

European Food Research and Technology (2021) 247:1939–1957 https://doi.org/10.1007/s00217-021-03762-6 ORIGINAL PAPER Investigation of different dietary‑fibre‑ingredients for the design of a fibre enriched bread formulation low in FODMAPs based on wheat starch and vital gluten Jonas J. Atzler1 · Aylin W. Sahin1 · Eimear Gallagher2 · Emanuele Zannini1 · Elke K. Arendt1,3 Received: 29 November 2020 / Revised: 13 April 2021 / Accepted: 17 April 2021 / Published online: 26 May 2021 © The Author(s) 2021 Abstract Consumption of fermentable oligo-, di-, monosaccharides and polyols (FODMAPs) often induces symptoms of irritable bowel syndrome (IBS). Since FODMAPs and dietary fibre (DF) share certain characteristics, IBS-patients have a limited intake of DF. Therefore, enrichment of a low FODMAP model bread (based on 84% wheat starch and 16% vital gluten) with various fibres (bamboo, cellulose, psyllium, guar gum) in two different concentrations (3 g/100 g and 6 g/100 g) was investigated. Physico-chemical properties of doughs and breads were analysed (fermentation quality, gluten development, specific volume and hardness), as well as the release of reducing sugars during in vitro digestion. High performance anion exchange chromatography with coupled pulsed amperometric detection (HPAEC-PAD) was used to determine the FODMAP levels (contents of mannitol, sorbitol, fructose in excess of glucose, fructans and α-galactooligosaccharides) of both dough and bread. Prototypes were compared with wheat flour-based breads (bakers’ flour with and without wheat bran addition) to assess the performance of these prototypes. Prototypes showed a decreased quality compared to a baker’s flour control, however, a quality comparable to commercial wheat bran breads was found. This in combination with a lower release of reducing sugars during in vitro digestion underline the potential of fibre enriched breads as part of a healthier and more palateable low FODMAP diet. Furthermore, this study highlights the importance of the type (viscous and insoluble) and the concentration of fibres used. Application of psyllium in a concentration of 3 g/100 g showed the most beneficial impact on both physical (specific volume, hardness after 0 h and 24 h) and nutritional aspects of bread. Keywords FODMAP · Irritable bowel syndrome · Dietary fibres · Functional foods * Elke K. Arendt Jonas J. Atzler Aylin W. Sahin Eimear Gallagher Emanuele Zannini 1 School of Food and Nutritional Sciences, University College Cork, College Road, Cork, Ireland 2 Teagasc Food Research Centre Ashtown, Ashtown, Dublin D15 KN3K, Ireland 3 APC Microbiome Ireland, Cork, Ireland Abbreviations IBS Irritable bowel syndrome DF Dietary fibre FODMAPs Fermentable oligo-, di-, monosaccharides and polyols HPAEC-PAD High-performance anionic exchange chromatography GI Glycaemic index GIT Gastrointestinal tract GOS α-Galactooligosaccharides BFC Baker´s flour control BFP Baker´s flour-based products LFC Low FODMAP control LFP Low FODMAP products TPC Total polyol content TOC Total oligosaccharide content 13 Vol.:(0123456789) 1940 Introduction Irritable bowel syndrome (IBS) is with a prevalence of 8–12% among the European population one of the most common bowel disorders [1]. Since symptoms of IBS can be caused by different factors, such as anxiety, stress and diet, the treatment uses various approaches including the adjustment of dietary habits [2]. Two highly recommended adjustments of dietary habits are to increase the intake of dietary fibre (DF) and to reduce the ingested amount of fermentable oligo-, di-, monosaccharides and polyols (FODMAPs) [3–7]. The European Food Safety Authority (EFSA) defines DF as carbohydrates which are not digestible in the human gastrointestinal tract (GIT) and have a scientifically proven beneficial effect on the GIT [8]. These effects include an increase of faecal mass, the support of the gut microbiota and a lowered glycaemic index (GI), which often lead to a relief of IBS symptoms [9–11]. However, the efficiency of the treatment and the impact on technical properties of the food products largely depend on the physical properties and the chemical structure of the fibre, such as solubility, viscosity and chain length [12]. DF can be divided into the following four main groups regarding their physicochemical properties and their fermentability: (a) soluble, highly fermentable DF; (b) intermediate soluble, fermentable DF; (c) insoluble, slowly fermentable DF and (d) insoluble, non-fermentable DF [7, 13]. Soluble DFs can also be separated according to their ability to form gel networks and their viscosity. The viscosity has been found to have a major beneficial effect on nutritional properties, e.g. lowering the total amount of cholesterol and the GI. Their ability to affect dough and bread properties, such as crumb hardness, in a positive way has been reported [7, 11, 14–17]. Insoluble fibres, such as cellulose and bamboo fibre, or wheat bran, additionally contribute to stool softening and an increased faecal mass. However, technological disadvantages of insoluble fibres, such as weakening of the gluten network or interfering with the gelatinisation of starch, have been researched and are reported [18–20]. Despite the general advantages of DF, clinical studies executed with IBS patients using wheat bran and psyllium showed either no relief or only a small improvement of symptoms [7, 13]. Therefore, a direct link between fibre intake and the improvement of IBS symptoms can not be confirmed. FODMAPS are hypothesised to increase the amount of luminal water via their osmotic activity and to increase gas volume through microbial fermentation which leads to the expansion of the colon and therefore to the occurrence of IBS symptoms [21]. Cereals, such as wheat and rye, and cereal-based products contribute to the fibre 13 European Food Research and Technology (2021) 247:1939–1957 intake, as well as to the FODMAP intake in the Western world [22–24]. Certain FODMAP compounds, such as fructans and α-galactooligosaccharides are considered dietary fibres since they possess certain characteristics, such as fermentability, indigestibility in the human gut and a degree of polymerisation of at least three. Therefore, the number of beneficial fibres suitable for a low FODMAP diet is limited. These restrictions could subsequently cause a negative effect on the GIT, such as a lower rate of defaecation and alteration of the gut microbiome [25]. Therefore, the fortification of food products based on low FODMAP ingredients with various DFs, which are not considered to belong to the FODMAP group has a high research potential. In recent years the research regarding the FODMAP reduction investigated various bio-technological approaches. Three promising approaches to reduce the FODMAP content in cereal-based products are the application of yeasts, sourdoughs and food-grade enzymes which are able to degrade fructa (...truncated)