Bread fortified with dietary fibre extracted from culinary banana bract: its quality attributes and in vitro starch digestibility

The effect of fortification of dietary fibre (DF) on dough rheology, quality characteristics and in vitro starch digestibility of bread was studied. Bread was prepared incorporating DF (2–4 g per 100 g of flour mixture). Rheological study of dough showed an increase in dough stiffness and elasticity with higher incorporation of the DF. The results of chemical composition revealed that addition of DF increased total DF (19.65 g per 100 g) content of bread. However, incorporation of 2 g per 100 g DF of flour mixture with 66 g per 100 g moisture showed higher water retention and specific volume of 86.76% and 5.83 cm³ g⁻¹, respectively, which was close to control bread. Improved textural property with acceptable sensory attributes was observed for bread fortified with 2 g per 100 g DF of flour mixture and 66 g per 100 g moisture content. Incorporation of DF (2–4 g per 100 g of flour mixture) showed a decrease in rapidly digestible starch (RDS) and an increase in slowly digestible starch (SDS) content with lower predicted glycaemic index (pGI) than control bread.     

Increasing the health benefits of bread: Assessment of the physical and sensory qualities of bread formulated using a renin inhibitory Palmaria palmata protein hydrolysate

This study examined the textural and sensory effects of bread formulated using a Palmaria palmata protein hydrolysate with in vitro renin inhibitory properties. Four formulations were examined; a wheat flour control bread, a control bread containing 4% P. palmata protein hydrolysate, a buckwheat bread consisting of a blend of 70% wheat: 30% buckwheat, and a fourth formulation of the buckwheat bread containing 4% P. palmata hydrolysate. The volume, colour, texture profile, moisture, crumb structure, sensory attributes and renin inhibitory activity of all four baked breads are presented. Bright field light microscopy and confocal scanning laser microscopy images using a new triple labelling protocol were also obtained to visualise the main ingredients of the breads. It was observed that the addition of 4% P. palmata protein hydrolysate to the wheat bread control did not affect the texture or sensory properties of the bread to a large degree. Furthermore, when compared to the control, the bread containing the hydrolysate retained renin inhibitory bioactivity after the baking process. This study highlights that baked products may be a suitable delivery vehicle for bioactive compounds. The study demonstrates that the health value of bread was increased through the addition of a seaweed protein hydrolysate.     

Substitution of wheat starch with non-wheat starches and cross-linked waxy barley starch affects sensory properties and staling of Arabic bread

Substitution of starch from barley, corn, oat, potato, rice or sorghum for prime wheat starch in the formulation of Arabic bread resulted in breads with significantly (P < 0.05) different textural attributes from regular wheat bread except for barley starch. Substitution of waxy barley starch (957 g kg⁻¹ amylopectin) for wheat starch (279 g kg⁻¹ amylopectin) resulted in bread that was not significantly different from regular wheat bread when assessed in the fresh state. However, upon aging, the waxy barley starch-containing bread staled at a significantly (P < 0.05) faster rate than regular wheat bread. Breads made with waxy barley starch cross-linked with 50, 200 or 500 ppm phosphorus oxychloride showed higher enthalpy of melting (ΔH) upon aging and staled faster than the bread formulated with waxy barley starch. These findings suggest that amylopectin retrogradation is one of the determinants of Arabic bread staling and that cross-linking promotes recrystallisation of amylopectin, possibly by keeping the polymer chains in close proximity. The rate of staling in breads formulated with cross-linked waxy barley starch decreased with increasing levels of cross-linking, possibly owing to restrictions in the degree of starch swelling. © 1999 Society of Chemical Industry     

Gluten‐free bread: multiple time–intensity analysis,physical characterisation and acceptance test

The formulation of gluten‐free breads is challenging, once the gluten network is responsible for the physical and sensory properties of bread. This study presents a novel concept for making gluten‐free breads using sugar substitutes. The quality of gluten‐free breads was analysed by means of physical (specific volume and colour), textural (firmness, elasticity and chewiness) and sensory properties (time‐intensity analysis and acceptance test). Time‐intensity analysis showed that the sample developed with raw sugar had a higher intensity of sweetness, and the sample with stevia had a higher intensity of yeast flavour. The sample with frutooligosaccharides (FOS) presented a higher acceptance by consumers. Sample with stevia presented the higher intensity of yeast flavour (8.10) and the lesser mean of specific volume (2.83 cm³.g^?1); whereas sample with sugar who presented higher intensity of sweetness stimulus (5.20) also presented the higher mean of specific volume (3.80 cm³.g^?1). The addition of prebiotic and sweetener opens up new opportunities to develop gluten‐free breads that may present similar properties to those of wheat‐based breads.     

Physical quality and in vitro starch digestibility of bread as affected by addition of extracted malva nut gum

Malva nut gum (MNG) was extracted by alkaline solution. The previous studies showed that the extract had viscosity and gelling properties as well as inhibited α-amylase activity in starch solution 1.5–2.0 folds higher than that of original malva nut gum. This research was aimed to investigate the α-amylase inhibitory effect of alkaline-extracted MNG in solid food and to determine physical properties of MNG-containing bread. The scanning electron microscopy of in vitro digestibility with α-amylase of MNG-containing breads showed less porosity and more undigested starch granules remained intact with the matrix compared to control. This finding was consistent with the reduction of glucose (33–40%) and maltose (23–39%) levels compared to that of control after α-amylase digestion for 180 min in a dialysis system. The results showed that extracted MNG significantly (p < 0.05) increased loaf volume, and moisture content by 1.5–12%, and 8.2–12.8%, respectively compared to that of control. Addition of extracted MNG in bread formulation significantly reduced moisture loss and firmness of the bread crumb after storage for three days.     

Potato flour as a functional ingredient in bread: evaluation of bread quality and starch characteristics

Potatoes have been added to bread for improvement of texture and moisture retention. The functional quality and starch digestibility in bread containing 5%, 10% or 15% potato flour were evaluated. Farinograph absorption of wheat and potato flour blends ranged from 59.0% to 77.7%. Bread with potato flour had significantly (P < 0.05) lower bread firmness during storage. There was a significant (P < 0.05) decrease in starch molecular weight as the level of potato flour increased. Inclusion of potato flour in these breads significantly (P < 0.05) increased the level of resistant starch (RS), while significantly (P < 0.05) decreasing the estimated glycemic index (eGI). Bread with no potato flour had 5.2% RS and an eGI of 95, while the bread with 15% potato flour had 11.3% RS and an eGI of 87. Overall, the addition of potato flour may reduce dough strength and loaf volume, but it reduced staling and increased resistant starch content of the bread.     

Quality of mashed potatoes: effect of adding blends of kappa-carrageenan and xanthan gum

Blends of kappa-carrageenan (K) and xanthan gum (X) were added to mashed potatoes. Product was tested by instrumental texture profile analysis and cone penetration tests, oscillatory and steady rheology, colour, drip loss, total soluble solids and sensory analyses. A central composite rotatable design was used to study the effects of variation in levels of K (1.5–4.5 g kg⁻¹) and X (0.5–2.5 g kg⁻¹) concentrations. Addition of K had a major impact on gel strength, viscoelastic behaviour, sensory attributes and overall acceptability, whereas addition of X influenced textural and steady properties and colour. Mainly, elastic modulus (G′) was strongly dependent on the K concentration in mashed potatoes containing amylose. As compared to mashed potatoes with 1.5 g kg⁻¹ added X, additional incorporation of 5.12 g kg⁻¹ K increased G′ approximately twofold, possibly due to exclusion effect of the swollen starch granules and synergistic effect of K and denatured protein. The function of X in the mashed potatoes may in fact be confined to that of a filler rather than a dynamic constituent, although it does affect yield stress behaviour. When K/X blends (each biopolymer at 1.5 g kg⁻¹) were included in the formulation, the product exhibited very acceptable sensory quality. K provided the appropriate texture, while X imparted creaminess and mouthfeel to the product.     

Physicochemical and nutritional properties of reduced-caloric density high-fibre breads

The influence of some physicochemical properties (chemical and nutritional composition, particle size, colour, dynamic viscosity, viscoelastic moduli) of associated binary mixtures of structuring hydrocolloids (cellulose derivatives, galactomannans) and prebiotic oligosaccharides (fructo- and gluco-oligosaccharides) in diluted hydrated wheat flour matrixes is discussed in terms of nutritional (higher resistant starch, lower digestible starch and lower in vitro Glycaemic Index) and technological functional profiles (higher sensory scores and longer keepability) of reduced-caloric density (−20%) high-fibre (>6 g/100 g) breads. Few technological functional (sensory firmness and overall acceptability) and most nutritional bread properties (protein digestibility, rapidly digestible starch, slowly digestible starch, in vitro expected Glycaemic Index, total digestible starch and resistant starch) were found to depend on dietary fibre molecular characteristics (mean particle diameter (D[4, 3]), storage modulus (G′), loss modulus (G″), complex viscosity (η*), and lactic acid solvent retention capacity. Dietary fibres with larger particle size resulted in highly sensory acceptable breads with higher amounts of resistant starch and slightly lower protein digestibility. Fibres exhibiting high viscoelasticity -G′, G″- and complex viscosity -η*- in concentrated solutions yielded breads with better sensory perception, lower digestible starch and higher resistant starch contents bringing to lower in vitro expected Glycaemic Index.     

Texture profile of fermented rice extracts with probiotic strains and different contents of waxy maize starch,and sensory acceptance of flavoured selected extract

Rice is a staple food for a great part of the world’s population, and its processing generates a great volume of low value by-products, such as bran and broken grains. This work aimed to elaborate fermented rice by-products extracts with probiotic strains and with different waxy maize starch (WMS) contents (0%, 4%, 8%, 12% and 16% w/w), in order to select one with texture profile similar to Greek-style yogurt, and to characterise the chemical composition and sensory acceptance of the selected extract added with artificial strawberry aroma and fresh strawberry syrup. The texture profile of the extract changed with WMS content and the 4% WMS fermented rice by-products extract was the most similar to Greek-style yogurt. The flavoured fermented rice by-products with WMS product presented 72.67% moisture, 2.55% protein, 0.2% lipid, 0.8% ash (340 mg 100 g⁻¹ of potassium), 27.4 µmol Trolox g⁻¹ and 134.74 mg GAE 100 g⁻¹ of phenolic compounds. The flavoured fermented rice by-products extract did not show microbiological risk and presented probiotic characteristic. Regarding the sensory analysis, it was observed that the aroma stood out among the other attributes, obtaining the highest score and acceptance index, while colour, flavour and texture scored ‘liked regularly to moderately’. The flavoured fermented rice by-products extract is an innovative product and feasible regarding the technological, physical, chemical, microbiological and sensory characteristics, having great potential to be inserted into the market.     

Effect of chitooligosaccharide from squid pen on gel properties of sardine surimi gel and its stability during refrigerated storage

Effect of chitooligosaccharide from squid pen prepared using lipase (COS-L) at various concentrations (0–30 g kg⁻¹) on gel properties of sardine surimi gel was investigated. Breaking force (BF) and deformation (DF) of gel were increased, when COS-L level was increased up to 10 g kg⁻¹ (P < 0.05). Water holding capacity and whiteness of gel were improved with the addition of COS-L than those of control. Gel added with 10 g kg⁻¹ COS-L had denser network with higher likeness score for all sensory attributes, compared to control. When gel incorporated with 10 g kg⁻¹ COS-L was stored at 4 °C, BF, DF and whiteness were maintained during 10 days of storage. Textural properties of surimi gel added with COS-L were higher than those of control throughout storage. Thus, incorporation of 10 g kg⁻¹ COS-L could improve gel properties of sardine surimi gel and retarded the deterioration of gel properties during refrigerated storage.     

Application of Glazing for Bread Quality Improvement

Glazing is a surface coating method for enhancement of the quality factors of bakery products. This study was intended to investigate the effect of different bakery glazing groups such as natural, polyols, sugars, and hydrocolloids on Barbari flat bread. Some quality attributes of bread such as moisture content, water activity, specific volume and width/height ratio (0 day) and hardness, crumb, and crust moisture (0–12 days) were evaluated. Results showed that vegetable oil treated samples had the lowest water activity and moisture content. Also, xanthan treatment provided the greatest effect on the specific volume of fresh bread, which enhanced it from 3.94 to 5 cm³/g. Vegetable oil, glycerol, dextrose, liquid glucose, and guar treatments had more significant effect on width/height ratio in comparison to nontreated (unglazed) bread. Evaluation of crumb hardness and moisture during 12 days storage implicated water, egg yolk, starch, and propylene glycol treatments were able to diminish the bread staling and these treated samples had the lowest crumb hardness. Crumb moisture of Barbari bread was affected mostly by water and starch treatments at day 12. Finally, our finding approved that using of glazing as a novel method is an effective technique for improvement of overall quality of flat bread and its application is suggested for large-scale production of other bakery products.     

Optimization of hydroxypropylmethylcellulose,yeast β-glucan,and whey protein levels based on physical properties of gluten-free rice bread using response surface methodology

Response surface methodology (RSM) was used to analyze effects of hydroxypropylmethylcellulose (HPMC), yeast β-glucan, and whey protein isolate (WPI) on physical properties of gluten-free bread baked from formulas based on rice starch. A Box–Behnken design with three independent variables (HPMC, yeast β-glucan, and WPI) and three levels was used to develop models for the different responses (physical properties). Individual contour plots of the different responses produced from the models were compared to the corresponding reference wheat bread data and were superimposed to locate gluten-free bread formulations that met the wheat bread standards for spread ratio, specific volume, hardness, cohesiveness, chewiness, and crumb color L∗ value. The optimal formulation, determined from the data, contained 4.35 g/100 g HPMC, 1 g/100 g β-glucan, and 0.37 g/100 g WPI, rice starch basis. Predicted values of the optimized bread were experimentally tested and compared with the experimental wheat bread data. A good agreement among these data was observed. Moreover, the optimized rice starch bread was found to be acceptable according to the results of sensory analysis.     

Impact of Heat Moisture Treatment and Hydration Level of Flours on the Functional and Nutritional Value-Added Wheat-Barley Blended Breads

The impact of heat moisture treatment (HMT) of flours on the techno-functional and nutritional patterns of binary flour bread matrices (wheat/barley, WT/CB, 60:40, w/w) was investigated in untreated (?) and HMT (+) samples made at 160 and 170 dough yield (DY) levels. Assessment was performed by determining viscoelastic (stress relaxation test) and mechanical (double compression test) behaviours, volume (seed displacement), colour (Photoshop system), crumb grain (digital image analysis), starch digestibility (enzyme hydrolysis) and staling kinetics (Avrami equation), bioaccessible polyphenol content (digestive enzymatic mild extraction) and anti-radical activity (DPPH●). A superior functional profile was provided by HMT of CB flour in the blend WT?CB+ when hydrated at DY 170 compared to the untreated control WT?CB?. The sample exhibited a similar specific volume, more cohesive, springier, more resilient crumb, with similar rate and extent of crumb firming on ageing, and similar colour pattern but finer and more uniformly sized cell structure, and deserved similar sensory ratings as the control WT?CB? concerning cell uniformity, smoothness and typical smell and taste. Digestible starch kinetic curves of blended breads pointed out samples WT?CB+ and WT+CB+ as matrices expliciting a lower degree and slower rate of starch hydrolysis when mixed at low and high DY, respectively. A similar anti-radical activity for composite bread matrices was evidenced regardless of either HMT or DY.     

Effect of the Addition of Different Dietary Fiber and Edible Cereal Bran Sources on the Baking and Sensory Characteristics of Cupcakes

The effect of successively replacing (10%, 20%, and 30%) wheat flour with dietary fiber (DF) from wheat, oat, barley, and maize or cereal bran (CB) from wheat, oat, and rice on cake batter, final cake quality parameters, as well as on product shelf-life was studied. Batter viscosity (control, 2.96; wheat fiber 30%, 20.21; rice bran 10%, 0.47 Pa sⁿ), cake-specific volume (control, 2.27; wheat fiber 20%, 2.83; rice bran 30%, 1.94 cm³/g), porosity (control, 0.75; wheat fiber 30%, 0.81; rice bran 30%, 0.69), and crumb moisture content (control, 20.07%,; wheat fiber 30%, 26.45%; oat bran 30%, 13.89%) increased significantly (P < 0.05) with DF addition but decreased with CB addition. Addition of DF resulted in softer crumb texture (Control, 4.20 N; wheat fiber 20%, 3.19 N), while CB addition increased crumb firmness (rice bran 30%, 10.84 N), respectively. Minor differences were observed in the crumb and crust color of the DF cakes with respect to the control. Addition of CB decreased the L values of crumb color significantly and the decrease increased with increased level of CB incorporation. DF addition led to cakes with greater acceptance by panelists than CB addition, similar to the control. DF cakes stored in polyethylene bags at 25 °C and 60% relative humidity for 6 days showed delayed moisture loss and lower firmness compared to CB cakes. The optimal level of incorporation based both on the objective and sensory characteristics results was found 20% for DF and 10% for CB, respectively. Concluding, by incorporating DF or CB properly, cakes with improved nutritional value can be manufactured.     

Okara flours from chickpea and soy are thickeners: increased dough viscosity and moisture content in gluten-free bread

The by-product of plant-based beverages, okara, can be dried in a nutritious flour, but it generates dense bakery products due to high water absorption. Gluten-free bread often tastes dry, so the objective of this work was evaluating okara flour as thickener for mouthfeel enhancement. Proximate analysis revealed that chickpea okara contained more starch than soy (35.3 vs. 3.41 g/100 g), less insoluble fibre (43.3 vs. 57.0 g/100 g) and protein (9.51 vs. 18.1 g/100 g). Water absorption capacity was higher in okara than flour and for soy (8.29 vs. 6.01 g g⁻¹, respectively). When added to a gluten-free batter, both okara flours significantly increased viscosity. Upon addition of either okara to gluten-free bread (2% w/w) moisture content increased from 31.6 to 33.5 and 36.5 g/100 g, while crumb hardness increased by up to 45% and specific loaf volume decreased by up to 42%. Soy okara flour enhanced moistness of gluten-free bread.     

Effect of dietary fibre enrichment on selected properties of gluten-free bread

The enrichment of gluten-free baked products with dietary fibre seems to be necessary since it has been reported that coeliac patients have generally a low intake of fibre due to their gluten-free diet. In the present study different cereal fibres (wheat, maize, oat and barley) were added at 3, 6 and 9 g/100 g level into a gluten-free bread formulation based on corn starch, rice flour and hydroxypropyl methyl cellulose (HPMC). Doughs were evaluated based on consistency, viscosity and thermal properties. Results showed that maize and oat fibre can be added to gluten-free bread with positive impact on bread nutritional and sensory properties. All breads with 9 g/100 g fibre increased the fibre content of control by 218%, but they were rated lower than those with 3 and 6 g/100 g fibre due to their powdery taste. The formulation containing barley fibre produced loaves that had more intense color and volume comparable to the control. During storage of breads a reduction in crumb moisture content and an increase in firmness were observed. The micrographs of the crumb showed the continuous matrix between starch and maize and/or oat fibre obtaining a more aerated structure.     

Influence of four different coagulants on the physicochemical properties,textural characteristics and flavour of tofu

The coagulation mechanism and quality characteristics of tofu depend on the choice of coagulant. The effects of using magnesium chloride (MgCl₂), calcium sulphate (CaSO₄), glucono-δ-lactone (GDL) and fermented soybean whey (FSW) as coagulants for tofu were investigated using solid-phase microextraction (SPME), two-dimensional gas chromatography coupled with mass spectrometry (GC×GC-MS), scanning electron microscopy (SEM) and analysis of textural characteristics and physicochemical properties. Results showed that GDL tofu exhibited the highest yield (202 g 100 g⁻¹) and moisture content (76.3%). FSW tofu had the highest protein content (18.5%), amino acid content (15.85%) and textural properties. GC×GC-MS analysis revealed the number of 49, 44, 55 and 63 flavour substances, respectively. In sensory evaluation tests, GDL tofu was reported to possess a smooth surface and white colour. The microstructure of FSW tofu was dense and uniform. Through the above technical researches, the study suggested FSW gave tofu the best quality, more unique flavour and more potential popular among consumers.     

Physicochemical properties of steamed bread fortified with ground linseed (Linum usitatissimum)

Chinese steamed bread (CSB) is a staple food among Asian populations. Linseed (Linum usitatissimum) is an emerging ‘healthy’ food ingredient rich in a range of bioactive components. Ground linseeds were incorporated in northern style CSB formulation up to 20%. Various physico-chemical, nutritional and sensory properties of the resulting CSB were studied. Linseed addition decreased the specific volume and spread ratio of CSB, while increasing the hardness and chewiness in a dose-dependent manner. Linseed addition up to 15% little affected the overall sensory acceptability of CSB. Nutritionally, linseed addition increased the in vitro antioxidant activities of CSB, while decreasing in vitro starch digestibility and expected glycaemic index. It may be concluded that linseed has the potential to enhance the nutritional quality of CSB without negatively affecting the eating quality.     

Green banana starch enhances physicochemical and sensory quality of baru almond-based fermented product with probiotic bacteria

This study aimed to isolate and characterise green banana starch (GBS) and to investigate the effect of adding 0%, 1.5%, 3.0%, 4.5% and 6.0% GBS on physicochemical and sensory properties of a fermented product based on baru almond (Dipteryx alata Vogel) water extract with probiotic bacteria. GBS showed high gelatinisation temperature (73.37 °C), enthalpy (16.61 J g⁻¹) and final viscosity (239.6 RVU). On the contrary, it showed a low tendency to retrograde (67.53 RVU), water solubility (0.02%), water absorption (1.85 g g⁻¹) and gel hardness (6.7 N). Higher addition levels of GBS increased firmness, reduced syneresis and positively affected pH, titratable acid, soluble solids and colour of baru almond-based fermented products. The incorporation of 4.5% GBS was well accepted and preferred over the control sample (no GBS addition). GBS can be used as a natural thickener. The baru almond-based fermented product with 4.5% GBS stands out for having potential probiotic properties and for being a promising dairy alternative.     

High-Legume Wheat-Based Matrices: Impact of High Pressure on Starch Hydrolysis and Firming Kinetics of Composite Breads

The significance of high hydrostatic pressure (HHP) processing on the physico-chemical—techno-functional and firming kinetics—parameters and nutritional properties—nutritional composition and “in vitro” starch digestibility—of highly replaced wheat flour breads by chickpea, pea and soybean flours was investigated, and the power/effectiveness of HHP in partially replacing structural agents (gluten and/or hydrocolloids) was discussed. Incorporation of pressured legume slurries (350 MPa, 10 min) at 42% of wheat replacement into bread formulation provoked a general increase in initial crumb hardness and browning of the crust with a concomitant explicit reduction of moisture, whiteness of the crumb and bread specific volume, but a slower in vitro starch digestibility with prominent formation of slowly digestible starch and resistant starch, compared to their counterparts prepared by using a conventional gluten/carboxymethyl cellulose (CMC)-added breadmaking recipe/process. Pressured breads with no gluten but 3% CMC in the formulation kept higher sensory ratings, softer initial texture and lower firming profiles on ageing than pressured breads with no gluten nor CMC. HHP has proven to be an effective technology to partially replace structuring agents (CMC and/or gluten) in high-legume wheat-based matrices providing sensorially acceptable breads with medium physico-chemical quality profile but enhanced formation of nutritionally relevant starch fractions and slower crumb firming kinetics on ageing.