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Background Irritable bowel syndrome (IBS) is one of the most common gastro-intestinal disorders worldwide and is often treated by adjusting the diet of IBS patients. An increased intake of dietary fibre (DF) and a limitation of the intake of fermentable oligo-, di-,monosaccharides and polyols (FODMAP) are the two dietary adjustments which are frequently recommended for people suffering from IBS. However, one challenge of a diet low in FODMAPs is the limited number of suitable dietary fibres. Scope and approach The aim of this overview is to identify characteristics and DFs beneficial for IBS patients by comparing the physico-chemical properties of FODMAPs and DFs. Therefore, relevant literature about DFs and FODMAPs was collected and summarised. These characteristics and the associated technological properties were used for a selection of DFs which can be used to develop food products with an increased fibre content and a lower FODMAP content while assuring the product quality expected by the consumer. Key findings and conclusions A low fermentation rate, low osmotic activity, insolubility and a high viscosity of soluble DFs have been identified as characteristics which are beneficial independent from the type of IBS. Soluble and non-viscous DFs can be beneficial depending on the occurrence of diarrhoea and their state of hydration. This finding highlights the importance of targeting a specific type of IBS. The above mentioned characteristics and the list of suitable DFs provide a good base for the development of functional foods and for future research regarding DF supporting the needs of IBS patients.

Brewer’s spent grain (BSG) is the main side-stream of brewing. BSG is a potential source for nutritionally enriched cereal products due to its high content of fibre and protein. Two novel ingredients originating from BSG, EverVita FIBRA (EVF) and EverVita PRO (EVP), were incorporated into bread in two addition levels to achieve a ‘source of fibre’ (3 g/100 g) and a ‘high in fibre’ (6 g/100 g) nutrition claim for the breads. The impact of those two ingredients on dough and bread quality as well as on nutritional value was investigated and compared to baker’s flour (C1) and wholemeal flour (C2) breads. The addition of EVF performed outstandingly well in the bread system achieving high specific volumes (3.72–4.66 mL/g), a soft crumb texture (4.77–9.03 N) and a crumb structure comparable with C1. Furthermore, EVF barely restricted gluten network development and did not influence dough rheology. EVP increased the dough resistance (+150%) compared to C1 which led to a lower specific volume (2.17–4.38 mL/g) and a harder crumb (6.25–36.36 N). However, EVP increased the nutritional value of the breads by increasing protein content (+36%) and protein quality by elevating the amount of indispensable amino acids. Furthermore, a decrease in predicted glycaemic index by 26% was achieved and microbial shelf life was extended by up to 3 days. Although both ingredients originated from the same BSG, their impact on bread characteristics and nutritional value varied. EVF and EVP can be considered as game-changers in the development of bread fortified with BSG, increasing nutritional value, and promoting sustainability.

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.

The addition of sprouted grains and seeds to cereal products has been identified as one of the upcoming trends in recent market reports. In this study, seven types of sprouts (amaranth, brown millet, corn, lentil, lupin, pea, quinoa) were milled and characterised with respect to their compositional (starch, protein, fat, ash, fibre, moisture) and functional properties (water hydration properties). These sprouted flours were included in a gluten-free bread formulation at a level of 5% and the impact on dough (temperature-dependent rising behaviour, pasting and rheological properties) and bread quality parameters (volume, crumb structure and texture) was evaluated. Factors such as the method of germination and the botanical origin influenced the chemical composition of the applied raw material. The functional properties of the different malts and sprouts are affected by the chemical composition of the individual grains. The differences in functional properties were, in turn, found to affect the dough properties and the quality parameters of the baked gluten-free breads. However, statistical analysis showed no correlation between the various factors. Based on this, effects on dough and bread properties were hypothesised to be caused by a combination of multiple factors. All bread formulations containing sprouted flour had significantly improved bread quality parameters in comparison to the control (without sprouted flour). The addition of amaranth sprouted flour, however, resulted in the highest loaf volume and the softest breadcrumb, suggesting its potential for further investigations in further studies.

Yeasts have been used for centuries for the leavening of bread. The main emphasis on the selection of yeast strains has been in relation to wheat products. This study is the first evaluation of different yeasts coming from the baking and brewing industry in a gluten-free system. Five different yeast strains (US-05, WB-06, T-58, S-23 and baker’s yeast) of the species Saccharomyces cerevisiae were evaluated for their suitability to leaven gluten-free dough. A wide range of dough quality characteristics such as the time and temperature-dependent rising behaviour, the chemical composition of the dough and the pH were determined. In addition to this, the bread quality attributes like, volume, texture, structure, aroma and flavour were evaluated. Obtained results indicated different activity levels between the selected yeast strains. Doughs prepared with US-05 showed a slower dough rise during proofing and a decreased height, in comparison to the baker’s yeast control. The application of WB-06 and T-58, however, resulted in a faster dough rise and increased dough height with greater gas cells (p < 0.05). These observations were also found in the baked breads, where these two yeasts reached a higher specific volume and a softer breadcrumb than the baker’s yeast bread (p < 0.05). Statistical analysis revealed strong correlations (p < 0.05) between activity level, dough properties and bread properties. Results obtained showed that the selected yeast strains reached different level of activity due to diverse preferences in temperature, time and sugars. Yeast strains which originated from the brewing industry were found to be suitable for gluten-free bread making.

Non-alcoholic beer (NAB) is enjoying growing demand and popularity due to consumer lifestyle trends and improved production methods. In recent years in particular, research into the application of non-Saccharomyces yeasts to produce NAB via limited fermentation has gained momentum. Non-Saccharomyces yeasts are known to produce fruity aromas, owing to a high ester production. This trait could be harnessed to mask the often-criticized wort-like off-flavor of NAB produced via limited fermentation. Six Cyberlindnera strains were characterized and screened in wort extract. Four of the six strains produced a pleasant, fruity aroma while exhibiting low ethanol production. The strain Cyberlindnera subsufficiens C6.1 was chosen for fermentation optimization via response surface methodology (RSM) and a pilot-scale (60 L) brewing trial with subsequent sensory evaluation. A low fermentation temperature and low pitching rate enhanced the fruitiness and overall acceptance of the NAB. The NAB (0.36% ABV) produced on pilot-scale was significantly more fruity and exhibited a significantly reduced wort-like off-flavor compared to two commercial NABs. This study demonstrated the suitability of Cyberlindnera subsufficiens to produce a fruity NAB, which can compete with commercial NABs. The outcome strengthens the position of non-Saccharomyces yeasts as a serious and applicable alternative to established methods in NAB brewing.

Brewer's Spent Grain (BSG), rich in fibre and protein is mostly used for animal feed but has great potential to be used as an ingredient for cereal based products. Originated from BSG, the two ingredients EverVita Fibra (EVF) high in fibre; and EverVita Pro (EVP) high in protein, were used to produce fibre-enriched pasta and compared to semolina, wholemeal flour and a commercial fibre-rich pasta. Analysis of gluten network development and pasting properties revealed the formation of a stronger network by the incorporation of EVP resulting in a compact pasta structure which led to a higher pasta firmness and tensile strength and a decrease in predicted glycaemic index compared to the controls. EVF resulted in an inferior product compared to EVP but was comparable to the semolina control. Hence, EVF and EVP have the potential to increase nutritional value of pasta while maintaining or even improving pasta quality and encouraging the recycling of by-streams for food production.

Cereals and pulses often contribute to the intake of Fermentable Oligo-, Di-, Monosaccharides, and Polyols (FODMAPs) due to high amounts of fructans or galactooligosaccharides (GOS). FODMAPs can trigger symptoms of Irritable Bowel Syndrome (IBS) and therefore, the development of foods and beverages with a lower FODMAP-content are favourable for IBS patients. Enzyme technology is a promising tool to reduce the FODMAP-content in foods and to maintain product quality. This fundamental study investigates the efficiency of invertase, inulinase, and α-galactosidase as potential food additives to reduce the total FODMAP content of food ingredients. Extracts of high FODMAP ingredients, such as wheat and lentil, and standard solutions of various fructans and GOS were incubated with invertase, inulinase and α-galactosidase for 1 h and 2 h. Contents of oligosaccharides before and after treatment and related IBS-triggering reaction products were quantified using ion chromatography. Inulinase showed a high degradation yield (over 90% of degradation) for both GOS and fructans. For invertase only low degradation yields were measured. α-Galactosidase showed the highest efficiency in decomposing GOS (100% of degradation) and led to non-IBS triggering degradation products. This indicates a high potential for a combined inulinase/α-galactosidase treatment for products containing both fructans and GOS.

Als Alternativen zu Tierversuchen bieten sich fur viele Fragestellungen in vitro-Tests mit tierischen oder anderen Zellen an. 96 Well-Mikrotiterplatten erlauben eine grose Anzahl von Versuchen unter gleichen Bedingungen (Zeit, Temperatur, etc.) durchzufuhren. Die Quantifizierung solcher Tests erfolgt bisher anhand von indirekten Zellzahlbestimmungen oder direkter Zellzahlung nach dem Absaugen der Zellen aus den Wells. Diese Methoden sind alle Endpunktbestimmungen und konnen daher nur einmal pro Platte durchgefuhrt werden. Sei es die Quantifizierung uber den Einbau radioaktivmarkierter Nucleotide wie Thymidin (Hewlett G. et al., 1989), oder die Aktivitatsbestimmung von “Marker-Enzymen”, wie mitochondriale Dehydrogenasen mit MTT (Mosmann T., 1983), XTT (Paull K.D. et al., 1988), oder MTS (Baltrop J.A. et al., 1991) als chromogenem Substrat, wie Laktat-Dehydrogenase (Racher A.J. et al., 1990), wie Saure Phosphatase (Conolly D.T. et al., 1986) etc., erlaubt nur eine einzige punktuelle Momentaufnahme pro Platte, deren Ergebnis nicht nur von der vorhandenen Zellzahl, sondern auch vom Aktivierungsgrad der Zellen abhangig ist. Alle kinetischen Parameter und die gesamte Entwicklung des Versuches bis zum gemessenen Endpunkt bleiben bei diesen Methoden als “black box” verborgen.