a b s t r a c tThe lower intake of fibre and fibre-containing foods has refocused the food industry on the benefits of incorporating different fibres in the foodstuff. Nowadays, a whole range of fibres are available in the market, but sometimes a good choice becomes complicated due to their varied physico-chemical properties. In order to give some light when selecting fibres, a comparative study regarding some physical properties of commercial fibres from different sources is presented, with a view to increasing their use in food products, namely bakery products. Commercial fibres included in this study were hydroxypropylmethylcellulose, cellulose, locust bean gum, guar gum, inulin, galactooligosaccharides, oat and wheat fibres, and fibres extracted from apple and bamboo. Particle size distribution (PSD) of the dry commercial fibres ranged from around 10 to 334 lm; moreover PSD in wet (water and ethanol) form was also determined to have precise information about their behaviour when processing. Cereal fibres (oat 600 and wheat) exhibited the highest values for hydration properties (swelling, water holding and water binding capacity). Only the hydrocolloids (HPMC, locust bean gum and guar gum), with the exception of cellulose, yielded highly viscous solutions during the heating-cooling cycle; moreover oat 600 and apple fibre developed viscous solutions after cooling. HPMC, locust bean gum and guar gum significantly augmented the four SRC values, thus those hydrocolloids affected the relative contributions to water absorption of proteins, carbohydrates, damaged starch and pentosans. Fibre sources and degree of replacement significantly affected the SRC values for the four solvents in all the fibre groups, with the exception of lactic acid SRC in the case of cereal fibres. Differences in fibres effect on wheat flour quality can be easily detected by assessing solvent retention capacity, which can give information on the end use functionality of the wheat flour.

13Dietary fiber incorporation into bread dough systems greatly interferes with 14 protein association and behavior during heating and cooling. The objective of this 15 study was to understand the individual and combined effects of dietary fibers on 16 dough behaviour during mixing, overmixing, pasting and gelling using the Mixolab® 17 device. Impact of different commercial dietary fibers (inulin, sugar beet fiber, pea cell 18 wall fiber and pea hull fiber) on wheat dough mixing, pasting and gelling profiles has 19 been investigated. Mixolab® plots indicates that the incorporation of sugar beet fiber 20 into the dough matrix induces the disruption of the viscoelastic system yielding 21 weaker doughs and it greatly competes for water with starch affecting pasting and 22 gelling. Conversely, inulin in the range tested seems to integrate into the dough 23 increasing its stability. Additionally, the responses acquired with this device were 24 compared with those obtained with other available methodologies, such as the 25Brabender Farinograph and the Rapid Visco Analyser, to explore its use as a suitable 26 technique for studying fiber enriched bread dough physical properties. A broad range 27 of correlation between Mixolab® and traditional devices were found. 28 29 2

No abstract

Fibre enriched baked goods have increasingly become a convenient carrier for dietary 24 fibre. However, the detrimental effect of fibres on dough rheology and bread quality continuously encourages food technologists to look for new fibres. The effect of several 26 fibres (Fibruline, Fibrex, Exafine and Swelite) from different sources (chicory roots, sugar beet and pea) on dough mixing properties when added singly or in combination has been 28 investigated by applying a response surface methodology to a Draper-Lin small composite design of fibre enriched wheat dough samples. Major effects were induced on water 30 absorption by Fibrex that led a significant increase of this parameter, accompanied by a softening effect on the dough, more noticeable when an excess of mixing was applied. 32Conversely, Exafine increased water absorption without affecting the consistency and stability of dough, which even improved when combined with Swelite. Fibruline showed 34 little effect on dough mixing parameters, but showed synergistic effects with pea fibres.The overall results indicates that the use of an optimised combination of fibres in the 36 formulation of fibre enriched dough allow improving dough functionality during processing. 38Key words: dietary fibre, wheat dough, rheology, mixing dough properties. 40 48 associated plant compounds [1]. The beneficial effects of the dietary fibres for human health include laxation [2], reduction of cardiovascular disease incidence [3-4] and 50 cholesterol level, and the risk of colon cancer [5-6]. 52The increasing demand for healthier foods has motivated food technologists to design fibre-enriched products. From the technological view, fibres are included in food recipes, 54 varying their uses from bulking agent to fat replacers. When added to a food matrix they can change its consistency, texture, rheological behaviour and sensory characteristics of 56 the end product [7][8][9]. In baked goods, one major difficulty when dealing with fibres is their detrimental effect on consumer acceptance, due to the reduction of loaf volume, the 58 increase of crumb hardness, the crust darkness and sometimes the effect on taste [7,[10][11][12][13]. Those drawbacks together with the healthy benefits provided by the fibre 60 supplementation have motivated the presence in the market of numerous fibres from different sources that might solve the mentioned problems leading to enriched fibre breads 62 with similar quality to white breads. Inulin, pea fibre, sugar beet fibre, and also fibres from cocoa, orange, coffee, sugarcane bagasse and rice straw have been lately incorporated to 64 wheat flour in order to improve the quality of the fibre enriched breads [7][8][9]13]. The effect of those fibres on dough rheology and bread quality was greatly dependent on fibre 66 properties, and opposite effects were frequently encountered. Previous studies were mainly focused to the individual incorporation of different fibres in order to determine their

a b s t r a c tThe technological functionality of different fibers (high methylated ester pectin, resistant starch, insoluble-soluble fiber blend) was tested in partially baked breads stored either under sub-zero or low temperatures, in order to assess their possible role as breadmaking ingredients in bake off technologies (BOT). Fiber-containing formulations affected bread specific volume and crumb hardness, and those characteristics were also dependent on both the breadmaking process (conventional or BOT) and the storage conditions of the par-baked bread (low or sub-zero temperatures). The inclusion of resistant starch (RS) and fiber blend in the bread formulation induced a reduction in the specific volume of the bread and an increase of hardness. Crumb image analysis indicated that breadmaking process affected significantly the number of alveoli. The storage of par-baked breads at low temperatures accelerates crumb hardening during staling, and that effect was greatly dependent on the duration of the storage, being that effect magnified in the case of breads containing fiber blend. Therefore, formulations should be carefully checked with the specific breadmaking process to be followed. Special attention should be paid to the storage conditions of the partially baked bread, since they significantly affect the technological quality of fresh breads and their behaviour during staling.

The aim of this research was to optimize mixtures of fibers from different sources and degree of processing meeting acceptable dough viscometric standards to design low‐calorie wheat bread formulations. Effects of soluble (inuline [FN]), partially soluble (sugar beet [FX]), pea cell wall (SW), and insoluble (pea hull [EX]) dietary fibers on wheat dough pasting and gelling profiles have been investigated. Impact of fibers added singly and in associated mixtures at different levels on the investigated viscometric parameters retrieved from a Rapid Visco Analyser curve has been assessed by response surface methodology, and the thermal parameters derived from the cooking and cooling functional profile were correlated. Flour replacement up to 34% by fibers significantly provided a deleterious effect on pasting and gelling viscosity profiles of the resulting hydrated high fiber‐flour blends. The magnitude of the reduction in dough viscometric characteristics during gelatinization, pasting, and setback closely depended on the nature of the fibers in the blend and on the extent of the flour substitution. A delayed and restricted swelling of starch granules and amylose leaching process preferentially achieved by the pair FN‐FX resulted in higher pasting temperatures and reduced peak viscosities during cooking and a sharp decrease of the setback on cooling. Single addition of FX, FN, and EX, respectively, provided a significant decrease in both breakdown viscosity and viscosity at the end of 95°C. Simultaneous presence of FN and EX that exhibit medium or low hydration properties allowed a partial restoration of initial breakdown viscosity and a simultaneous decrease in holding strength. Caution should be paid to the pairs FN‐FX and EX‐SW because of the adverse extra decline they induced in the viscosities of both hot paste and cold gel.

Cereal Chem. 85(4):455-463The impact of dietary fiber (DF) mixtures on dough thermal properties needs to be investigated when designing high-fiber wheat bread. Effects of flour replacement at different levels (6-34%) by soluble (inuline [FN]), partially soluble (sugar beet [FX], pea cell wall [SW]), and insoluble (pea hull [EX]) DF on wheat dough thermal profiles have been investigated by simulating baking, cooling, and storage in differential scanning calorimetry (DSC) pans. In general, DF incorporation into water-flour systems delayed endothermic transition temperatures for both gelatinization and retrogradation phenomena except for the peak temperature (T p ) of

14The effect of different breadmaking processes (conventional, frozen dough, frozen 15 partially baked bread) and the effect of the storage periodon the technological quality of 16 the fresh wholemeal wheat breads are investigated. In addition, the impact of the 17 exogenous fungal phytase on the phytate content was also determined. Results showed 18 that breadmaking technology significantly affected the quality parameters of wholemeal 19 breads (specific volume, moisture content, crumb and crust colour, crumb texture 20 profile analysis and crust flaking) and frozen storage affected in different extent the 21 quality of the loaves obtained from partially baked breads and those obtained from 22 frozen dough, particularly crust flaking. Freezing and frozen storage of wholemeal 23 bread in the presence of fungal phytase decreased significantly the phytate content in 24 whole wheat breads. The combination of fungal phytase addition, breadmaking process 25 and frozen storage could be advisable for overcoming the detrimental effect of bran on 26 the mineral bioavailability.