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

Development and characterization of gluten-free fried dough (magwinya) using sorghum flour

Magwinya, a deep-fried cereal dough, is usually produced using cake or bread wheat flour due to the naturally beneficial proteins found in wheat. In this study, sorghum flour, a gluten-free cereal grain, was used to produce magwinya. The aim was to develop and characterize gluten-free fried dough using sorghum flour. Xanthan and guar gum hydrocolloids were added to the sorghum flour in ratios of 0.5%, 1.0%, and 1.5% and 1.5%, 2.0%, and 2.5%, respectively, for magwinya production. The physicochemical characteristics of the magwinya were compared. The hardness of magwinya was significantly lower in sorghum: guar gum (SGG) samples due to their high moisture content. Ash and fiber content were also significantly higher in SGG samples. Increasing the level of SGG increased the volume (63.33-66.67 cm3). There was no significant difference in the weight of the samples. An increase in diameter (50.33-52.17 mm) was observed in SGG samples. Color analysis showed a significant increase in the L* (Lightness) of the crumb (46.28-49.12) compared to the crust (26.96-30.11) in the SX (sorghum: xanthan gum) and SGG samples. Redness (12.28-13.77) increased with levels, while yellowness (11.86-14.02) decreased with levels in SX and SGG crust. This study's findings are significant as they indicate that guar gum was the better binder for developing cereal fried dough (magwinya) from sorghum. These findings could have practical applications in the food industry, particularly in the development of gluten-free products and in the use of alternative grains like sorghum.

The effects of different fiber fractions from sour cherry (Prunus cerasus L.) pomace and fiber modification methods on cake quality

Sour cherry pomace is the largest byproduct of sour cherry processing with more than 0.4 million tonnes per year. In this study, sour cherry pomace powder (SCPP) has been treated individually or by a combination of microwave (MW), enzymatic hydrolysis, and high pressure to increase soluble dietary fiber (SDF) content. Then, the untreated or treated forms of SCPP, their SDF, and insoluble dietary fiber (IDF) isolates were added (5%) to the reduced-fat cake. Rheological, physical, and textural properties of the full-fat (50%) and the reduced-fat (25% fat) cakes enriched with dietary fiber (DF) were compared. SDF enrichment minimized the negative effect of fat reduction in the cake. Water absorption, mixing tolerance, hardness, and springiness values of the SDF-enriched samples were found as the lowest. Extensibility, energy, weight loss, and cohesiveness values were found to be the highest values with the addition of SDF. All treatments helped to decrease mixing tolerance, dough development, and stability time. MW was the critical treatment for DF modification. Individual MW-treated DF samples increased resistance to extension of the dough samples as compared to the untreated SDF, IDF, and SCPP. Nevertheless, SDF showed better performance in acting as a fat replacer than IDF and SCPP. PRACTICAL APPLICATION: The soluble dietary fiber (SDF) isolate minimized the negative effect of fat reduction in cakes. Water absorption and mixing tolerance of the dough were measured as the lowest. The hardness and springiness of soluble dietary fiber-enriched cakes were found to be the lowest. Extensibility and weight loss reached the highest value when SDF was used. Treatments helped decrease mixing tolerance, dough development, and stability time.

Development and characterization of hydrogel-in-oleogel (bigel) systems and their application as a butter replacer for bread making

BACKGROUND

Butter has been widely used in bakery products and it contains high level of saturated fats. However, excessive consumption of saturated fats would increase the risk of chronic disease. This study was to fabricate water-in-oil (W/O) type bigels as butter replacers to improve the quality attributes of breads.

RESULTS

A stable water-in-oil (W/O) type bigel system was fabricated based on mixed oleogelators (rice bran wax and glycerol monostearate) and sodium alginate hydrogel. The ratios of oleogel to hydrogel could significantly affect the stability, microstructure and rheological properties of bigels. All of the bigels exhibited solid-like properties, with increased oleogel fractions, and the network structure of bigel became more compact and orderly with smaller sodium alginate gel particles. Meanwhile, the viscoelastic modulus and firmness of bigel increased, contributing to a higher stability. The bigel dough exhibited lower gel strength and relatively higher extensibility compared to the butter dough. Regardless of oleogel fractions, all the bigel produced bread with a higher specific volume and softer texture than the butter bread. When the oleogel fractions was less than 80%, increasing the oleogel fractions was more beneficial for improving the specific volume, softness and fluffy structure of bread.

CONCLUSION

W/O type bigel as butter replacers showed great potential in improving the appearance, structure and textural properties of bread. © 2023 Society of Chemical Industry.

Effects of White Sorghum Flour Levels on Physicochemical and Sensory Characteristics of Gluten-Free Bread

This research studied the effects of white sorghum flour levels at 0, 10, 25, 40, 70, 85 and 100% in the matrix of rice and tapioca flours and corn starch on the properties of flour blends and the qualities of gluten-free (GF) bread. Single and composite flours were analyzed for moisture content, color and pasting properties. GF bread samples prepared from composite flours were analyzed for specific volume, moisture content, water activity, crumb color and instrumental texture. Sensory profiles of the breads were determined by nine trained descriptive panelists. The results show that increasing the sorghum flour content increased (p ≤ 0.05) color intensity, pasting temperature and setback viscosity, while it decreased (p ≤ 0.05) the peak and breakdown viscosities of flour blends. For GF bread, increasing white sorghum flour levels in the blends primarily affected specific volume, color, flavor and texture characteristics, leading to decreases (p ≤ 0.05) in specific volume, cohesiveness, springiness, chewiness and moistness, but increases (p ≤ 0.05) in color intensity, brown and nutty flavors, graininess and roughness. White sorghum flour could be used in the blends at the maximum level of 25% to get a good bread volume without sacrificing texture quality.

Valorisation of Buckwheat By-Product as a Health-Promoting Ingredient Rich in Fibre for the Formulation of Gluten-Free Bread

Bread is a widely consumed food that has often been used as a vehicle for functional ingredients such as dietary fibre. Fibre-rich breads have beneficial physiological effects on health, helping to combat chronic pathologies such as cardiovascular disease, diabetes, and certain types of colon cancer. The aim of this study is to evaluate the technological and nutritional effects of the inclusion of buckwheat hull particles (BH) at two addition levels (3 and 6%) and two particle sizes (fine, D₅₀: 62.7 μm; coarse, D₅₀: 307 μm) in a gluten-free (GF) bread formulation. A significant (p < 0.05) increase in the dough elastic modulus (G') was observed for all doughs containing BH, from 712 Pa for a rice-based dough to 1027-3738 Pa for those containing BH. Compared to rice-based breads, those containing BH showed a significant (p < 0.05) increase in total dietary fibre content (from three to five times) and in antioxidant capacity (from 78 to 290 mg TE/100 g dw. in the ORAC test). Breads containing fine BH at a level of 3% had similar sensory properties to the rice-based bread, demonstrating that it is possible to improve the TDF content while maintaining the sensory quality of the GF bread.

The Nutritional Quality of Gluten-Free versus Non-Gluten-Free Pre-Packaged Foods and Beverages Sold in Hong Kong

INTRODUCTION

The consumption of gluten-free foods has continued to increase in recent years. Given their higher intake among individuals both with and without a medically diagnosed gluten allergy or sensitivity, it is important to understand how the nutritional quality of these foods compares against non-gluten-free foods. As such, we aimed to compare the nutritional quality of gluten-free and non-gluten-free pre-packaged foods sold in Hong Kong.

METHODS

Data from 18,292 pre-packaged food and beverage items in the 2019 FoodSwitch Hong Kong database were used. These products were categorized as (1) "declared gluten-free"; (2) "gluten-free by ingredient or naturally gluten-free"; and (3) "non-gluten-free" according to information presented on the package. One-way ANOVA was used to compare the differences in the Australian Health Star Rating (HSR), energy, protein, fibre, total fat, saturated fat, trans-fat, carbohydrates, sugars, and sodium content between products in different gluten categories, overall and by major food category (e.g., bread and bakery products) and region of origin (e.g., America, Europe).

RESULTS

Products declared gluten-free (mean ± SD: 2.9 ± 1.3; n = 7%) had statistically significantly higher HSR than those gluten-free by ingredient or naturally gluten-free (2.7 ± 1.4; n = 51.9%) and non-gluten-free (2.2 ± 1.4; n = 41.2%) (all pairwise comparisons p < 0.001). Overall, non-gluten-free products have higher energy, protein, saturated fat, trans-fat, free sugar and sodium, and less fibre compared with products in the other two gluten categories. Similar differences were observed across major food groups and by region of origin.

CONCLUSIONS

Non-gluten-free products sold in Hong Kong were generally less healthy than gluten-free products (regardless of the presence of gluten-free declaration). Consumers should be better educated on how to identify gluten-free foods, given that many gluten-free foods do not declare this information on the label.

Optimization of tannin-containing sorghum bran addition to gluten-free bread

Ingredients used to enhance sensory quality of gluten-free (GF) bread often lack in nutrients. This presents nutritional challenges for celiac-positive individuals and fails to meet expectations of healthfulness for non-celiac GF consumers. Sorghum (Sorghum bicolor L. Moench) flour can provide acceptable GF bread properties, and tannin-containing varieties contain antioxidants concentrated in the bran along with dietary fiber. Using a central composite design, tannin-containing sumac sorghum bran, gum (xanthan + guar), and water levels were optimized in a GF sorghum-based bread formulation. Loaf specific volume and gas cells/cm² were maximized while minimizing hardness and cell wall thickness. The optimum formulation containing 14.2% sorghum bran, 1% gum, and 145% water (flour basis) effectively increased dietary fiber in bread to 13.4% (considered "high fiber") and showed oxygen radical absorbance capacity of 61.6 µmol TE/g. This optimum formulation did not differ from a sorghum flour-based control bread in consumers' (N = 100) liking of color, texture, flavor, overall acceptability, nor willingness to buy (WTB). All mean hedonic scores (numbered 9-point scale) were above 5, whereas average WTB was 4.7 for the optimum formulation and 4.6 for the control (9-point Likert scale) among consumers varying in GF bread consumption habits. Perceived bread bitterness was low (averaging 2.85 on 9-point intensity scale), did not vary between samples despite marked differences in antioxidant capacity, and was not correlated with WTB. When utilizing effective optimization models with key functional ingredients, sumac sorghum bran addition can enhance dietary fiber and antioxidant potential in sorghum-based GF breads without compromising quality attributes.

Effect of sugar beet fiber and different hydrocolloids on rheological properties and quality of gluten-free muffins

BACKGROUND

Extraction of pectin from sugar beet pulp is a side production line to recover value-added by-products in a sugar refining company. We aimed to evaluate the influence of depectinized and non-treated fiber on the quality of food. Pectin was removed from sugar beet pulp, and sugar beet fiber with and without pectin extraction (F and FP respectively) were replaced with rice flour in gluten-free muffins. To achieve a consistent texture, different hydrocolloids (carrageenan, xanthan gum, guar gum, locust bean gum (LBG), and tara gum) were added to the batter formula.

RESULTS

The maximum batter viscosity was observed for the xanthan-containing formulation, followed by guar, tara, LBG, and carrageenan formulations. The highest hardness was recorded for baked muffins formulated with guar, followed by xanthan, carrageenan, tara, and LBG formula. Moisture retention was considerably increased in the presence of FP and LBG compared with muffins prepared by F and/or other hydrocolloids. However, muffins containing F showed the least hardness and highest cohesiveness, gumminess, springiness, and chewiness. The samples containing F represented lighter color, lower energy, and less porous in appearance compared with the FP formula. From a sensorial aspect, there was no significant difference between the F and FP formulas, but the control and sample with higher fiber content were not acceptable.

CONCLUSION

This study showed that depectinized sugar beet fiber a by-product of sugar factories, has the possible use in formulation of gluten-free muffins with no adverse effects on its quality. © 2022 Society of Chemical Industry.

Effect of Tartary Buckwheat Bran Substitution on the Quality, Bioactive Compounds Content, and In Vitro Starch Digestibility of Tartary Buckwheat Dried Noodles

This study aimed to investigate the impact of partial replacement of Tartary buckwheat flour (TBF) with Tartary buckwheat bran flour (TBBF) on the quality, bioactive compounds content, and in vitro starch digestibility of Tartary buckwheat dried noodles (TBDNs). When the substitution of TBBF was increased from 0 to 35%, the cooking and textural properties decreased significantly (p < 0.05), while the content of bioactive compounds (phenolic, flavonoids and dietary fiber) increased significantly (p < 0.05). In addition, the substitution of TBBF decreased the starch digestibility of TBDNs. A 10.4% reduction in eGI values was observed in the TBDNs with 35% TBBF substitution compared to the control sample. The results of differential scanning calorimetry showed that with the increase of TBBF, TBDNs starch became more resistant to thermal processing. Meanwhile, the X-ray diffraction and Fourier transform infrared spectroscopy results revealed that the long- and short-range ordered structures of TBDN starch increased significantly (p < 0.05). Furthermore, the substitution of TBBF decreased the fluorescence intensity of α-amylase and amyloglucosidase. This study suggests that replacing TBF with TBBF could produce low glycemic index and nutrient-rich TBDNs.

Milk Thistle Oilseed Cake Flour Fractions: A Source of Silymarin and Macronutrients for Gluten-Free Bread

The utilization of plant by-products as functional food ingredients has received increasing attention in the last decade. One such by-product generated during milk thistle oil pressing is oilseed cakes, which could be used as a novel food ingredient. Therefore, the study aimed at investigating the effects of the addition of milk thistle oilseed cake (MTOC) flour fractions obtained via dry sieving, differing in particle size (unsieved; coarse: >710 µm; medium: 315−710 µm; and fine: <315 µm), on the quality of gluten-free bread and stability of silymarin during breadmaking. The 10% addition of the fractions into gluten-free bread increased the protein, fibre, fat, ash and silymarin content. The breads with the coarse fraction had the highest content of fibre, whereas the breads with the fine fraction excelled in protein, fat and ash content. The medium fraction was characterized as the richest source of silymarin, whilst the fine fraction was the poorest. Silymarin constituents were slightly released during dough rising but also partially decomposed during baking; moreover, silydianin was the most susceptible and degraded the most. The enriched breads had better sensory and textural properties compared to the control bread. The results suggest that MTOC flour fractions can improve the potential health benefits and nutritional profile of gluten-free bread.

Application of New Sources of Bioactive Substances (Perilla frutescens L. and Tagetes erecta L.) in the Chosen Cookies Production

Today, one of the most important challenges of ensuring the society's health is the prevention of civilization diseases. Most of them are associated with an imbalance between antioxidants and free radicals in the human body. Due to the need to increase the intake of antioxidants, opportunities are being studied to increase their consumption. Therefore, the aim of this study was to evaluate the influence of plant extracts of marigold (Tagetes erecta spp.) (MEx) and perilla (Perilla frutescens L.) (PEx) on selected qualitative properties of muffins. We studied the effects of the extracts in amounts of 1% (1), 3% (3), and 5% (5) on selected muffin characteristics, i.e., crust and crumb color, cooking yield, specific volume, and water activity, and changes in textural properties as well as sensory acceptance analysis. The level of crust lightness (L*) of muffins was lower than that of the control sample only for the samples with the PEx. For the crumb, the muffins with MEx and PEx were darker than the control sample. Fortification of muffins resulted in a concentration-dependent increase in antioxidant capacity. The PEx_3 and PEx_5 samples were rated highest in the sensory acceptance evaluation. The other quality attributes were similar to the control sample, indicating the validity of introducing extracts in the muffin recipe.

Gluten-free bakery products: Ingredients and processes

There is an increasing demand for gluten-free products around the world because certain groups of people, which have increased in the last decades, need to eliminate gluten from their diet. A growing number of people consider gluten-free products to be healthier. However, making gluten-free products such as bread is a technological challenge due to the important role of the gluten network in their development. However, other products, such as cakes and cookies usually made with wheat flour, can easily be made with gluten-free starches or flours since gluten does not play an essential role in their production. To replace wheat flour in these elaborations it is necessary to resort to gluten-free starches and/or flours and to gluten substitutes. Additionally, it can be convenient to incorporate other ingredients such as proteins, fibers, sugars or oils, as well as to modify their quantities in wheat flour formulations. Regarding gluten-free flours, it will also be necessary to know the parameters that influence their functionality in order to obtain regular products. These problems have originated a lower availability of gluten-free products which have a worse texture and are less tasty and more expensive than their homologues with gluten. These problems have been partially solved thanks to research on these types of products, their ingredients and their production methods. In recent years, studies about the nutritional improvement of these products have increased. This chapter delves into the main ingredients used in the production of gluten-free products, the processes for making gluten-free breads, cakes and cookies, and the nutritional quality of these products.

Amorphophallus konjac: Sensory Profile of This Novel Alternative Flour on Gluten-Free Bread

This study aimed to evaluate the sensory profile of gluten-free bread with Amorphophallus konjac (AK) flour in different concentrations. This experimental study is divided into three steps: preparation of the gluten-free bread formulations, sensory analysis, and statistical analysis. The addition of Konjac flour in a gluten-free bread formulation was tested in different proportions, 12.5%, 25%, 37.5%, and 50% of the flour content. The checking all-that-apply (CATA) was conducted with 110 panelists; among these, 43 were consumers of gluten-free bread. Sensory analysis was conducted using a 9-point hedonic scale for color, aroma, texture, flavor, appearance, and overall acceptability. The AK flour influenced the sensory characteristics of gluten-free bread. Bread with characteristics closer to those found in bread with gluten was the one with 12.5% of konjac flour for both the acceptability analysis as the attributes raised through a detailed CATA map. The control sample is located next to features like dry appearance, dry texture and grainy, dark color, and salty. Therefore, 12.5% AK gluten-free bread is closer to the characteristics of the control sample, such as light crust color, light crumb color, soft and moist texture, cohesion, and brightness. The bread with the highest percentage of overall consumer acceptance was 12.5% konjac with 93% and 96% acceptance among consumers and non-consumers of gluten-free bread, respectively.

Potential use of plant-based by-products and waste to improve the quality of gluten-free foods

The food industry generates a large amount of waste and by-products, the disposal of which has a negative impact on the environment and the economy. Plant-based waste and by-products are rich in bioactive compounds such as dietary fiber, proteins, essential fatty acids, antioxidant compounds, vitamin, and minerals, which can be exploited to reduce the nutritional deficiencies of gluten-free products. The latter are known to be rich in fats and carbohydrates but lacking in bioactive compounds; the absence of gluten also has a negative effect on textural and sensory properties. Several attempts have been made to improve the quality of gluten-free products using alternative flours and additives, or by adopting innovative technologies. The exploitation of plant-based by-products would represent a chance to improve both the nutritional profile and the overall quality of gluten-free foods by further enhancing the sustainability of the agri-food system. After examining in detail the composition of plant-based by-products and waste, the objective of this review was to provide an overview of the effects of their inclusion on the quality of gluten-free products (bread, pasta, cake/muffins, biscuits and snacks). The advantages and drawbacks regarding the physical, sensory, and nutritional properties were critically evaluated. © 2021 Society of Chemical Industry.

Current Research and Applications of Starch-Based Biodegradable Films for Food Packaging

The use of biodegradable packaging material as an alternative to conventional petrochemical-based polymers is based on the environmental issues associated with conventional materials. This review aims to update the existing knowledge regarding the application of starch-based biodegradable films for food packaging. From the review, it was evident that starch stands out among biopolymers due to its abundance and cost effectiveness. This review is the first of its kind, having reviewed over 100 articles/publications on starch-based biodegradable films, consolidating their current state of research and their applications for food packaging; therefore, this review provides an insight into the utilization of nanomaterials to improve the shelf life of packaging of food.

Almond Hull as a Functional Ingredient of Bread: Effects on Physico-Chemical, Nutritional, and Consumer Acceptability Properties

Hulls are the principal almond by-products and are rich in bioactive compounds, such as polyphenols and fibre. Generally, hulls are used as animal feed; however, because of their valuable chemical composition, alternative applications as a natural food ingredient and dietary supplement should be evaluated. The aim of this study was to assess the physico-chemical and nutritional characteristics and the consumer acceptability of bread produced by replacing 4% and 8% of wheat flour with almond hulls (AHs) obtained from six almond varieties at two ripening stages (green and mature). The use of AHs in bread production increased fibre content, polyphenol content, and antioxidant activity. In particular, bread containing mature AHs showed the highest quantities of fibre and sugars, mainly glucose, whereas bread containing green AHs showed the highest polyphenol content. The polyphenol content and antioxidant activity in bread containing green AHs were 272.88 mg GAE/100 g dry weight and 1145.32 μmol TE/100 g dry weight, respectively, of which 60.5% and 52% were bioaccessible after in vitro digestion. Bread containing AH powder showed slightly lower specific volume, darker crumb colour, and lower hardness than those of the control. Consumer evaluation indicated that breads with 8% AH powder were those with the most overall liking.

Improvement of Texture, Nutritional Qualities, and Consumers’ Perceptions of Sorghum-Based Sourdough Bread Made with Pediococcus pentosaceus and Weissella confusa Strains

Enriched gluten-free products are in high demand owing to increasing celiac disease worldwide. Sourdough fermentation can improve the quality of gluten-free cereals, rendering the resulting product beneficial as a functional food. This study produced sorghum bread (SB) using sourdough technology and evaluated the texture, nutrition profile, bioactive components, and sensory attributes of the product. The base formula was composed of sorghum flour and corn starch. Sourdough made with Pediococcus pentosaceus LD7 (PL7), P. pentosaceus SA8 (PS8), or Weissella confusa SD8 (WS8) was added at a 20% substitution level for bread production, while bread without sourdough addition was used as the control sample. The texture profiles of the SB were significantly (p ˂ 0.05) softer than that of the control. The sourdough breads possessed higher crude protein, ash, and dietary fibre contents than the control bread. Tannin and total phenol contents were significantly (p ˂ 0.05) higher in the sourdough breads compared to the control sample. The specific volume of the sample made with PS8 sourdough was the highest at 2.50 cm3/g compared to the other samples (2.17–2.46 cm3/g). The sourdough samples had higher scores for taste, texture, aroma, and overall acceptability than the control, with PL7 SB exhibiting the best overall acceptability (6.56). This study established promising use of sourdough with starters as an ingredient for baked products with improved technological and nutritional attributes as well as consumer acceptability.

Delving into the Role of Dietary Fiber in Gluten-Free Bread Formulations: Integrating Fundamental Rheological, Technological, Sensory, and Nutritional Aspects

The evidenced relevance of dietary fibers (DF) as functional ingredients shifted the research focus towards their incorporation into gluten-free (GF) bread, aiming to attain the DF contents required for the manifestation of health benefits. Numerous studies addressing the inclusion of DF from diverse sources rendered useful information regarding the role of DF in GF batter’s rheological properties, as well as the end product’s technological and nutritional qualities. The presented comprehensive review aspires to provide insight into the changes in fiber-enriched GF batter’s fundamental rheological properties, and technological, sensory, and nutritional GF bread quality from the insoluble and soluble DF (IDF and SDF) perspective. Different mechanisms for understanding IDF and SDF action on GF batter and bread were discussed. In general, IDF and SDF can enhance, but also diminish, the properties of GF batter and bread, depending on their addition level and the presence of available water in the GF system. However, it was seen that SDF addition provides a more homogenous GF batter structure, leading to bread with higher volumes and softer crumb, compared to IDF. The sensory properties of fiber-enriched GF breads were acceptable in most cases when the inclusion level was up to 7 g/100 g, regardless of the fiber type, enabling the labeling of the bread as a source of fiber.

Natural plant fibers obtained from agricultural residue used as an ingredient in food matrixes or packaging materials: A review

Every year, agrifood activities generate a large amount of plant byproducts, which have a low economical value. However, the valorization of these byproducts can contribute to increasing the intake of dietary fibers and reducing the environmental pollution. This review presents an overview of a wide variety of agricultural wastes applied in the formulation of different food products and sustainable packaging. In general, the incorporation of fibers into bakery, meat, and dairy products was successful, especially at a level of 10% or less. Fibers from a variety of crops improved the consistency, texture, and stability of sauce formulations without affecting sensory quality. In addition, fiber fortification (0.01-6.4%) presented considerable advantages in terms of rheology, texture, melting behavior, and fat replacement of ice cream, but in some cases had a negative impact on color and mouthfeel. In the case of beverages, promising effects on texture, viscosity, stability, and appetite control were obtained by the addition of soluble dietary fibers from grains and fruits with small particle size. Biocomposites used in packaging benefited from reinforcing effects of various plant fiber sources, but the extent of modification depended on the matrix type, fiber pretreatment, and concentration. The information synthesized in this contribution can be used as a tool to screen and select the most promising fiber source, fiber concentration, and pretreatment for specific food applications and sustainable packaging.

The Effect of Arabinoxylan and Wheat Bran Incorporation on Dough Rheology and Thermal Processing of Rotary-Moulded Biscuits

Wheat bran incorporation into biscuits may increase their nutritional value, however, it may affect dough rheology and baking performance, due to the effect of bran particles on dough structure and an increase in water absorption. This study analyzed the enrichment effect of wheat bran and arabinoxylans, the most important non-starch polysaccharides found in whole wheat flour, on dough rheology and thermal behaviour during processing of rotary-moulded biscuits. The objective was to understand the contribution of arabinoxylans during biscuit-making and their impact when incorporated as wheat bran. Refined flour was replaced at 25, 50, 75, or 100% by whole flour with different bran particle sizes (fine: 4% > 500 μm; coarse: 72% > 500 μm). The isolated effect of arabinoxylans was examined by preparing model flours, where refined flour was enriched with water-extractable and water-unextractable arabinoxylans. Wheat bran had the greatest impact on dough firmness and arabinoxylans had the greatest impact on the elastic response. The degree of starch gelatinization increased from 24 to 36% in biscuits enriched with arabinoxylans or whole flour and coarse bran. The microstructural analysis (SEM, micro-CT) suggested that fibre micropores may retain water inside their capillaries which can be released in a controlled manner during baking.

Use of different proportions of rice milling fractions as strategy for improving quality parameters and nutritional profile of gluten-free bread

The growing consumer exigency and the lack of gluten-free (GF) bakery products with good technological and nutritional characteristics in the market have increase the need of researching in this area. Few studies have analysed the simultaneous influence of different flour fractions from rice dry milling to formulate GF bread and its effects on rheology and product quality. The aim of this study was to characterize the chemical and physical properties of rice milling fractions (flour, coarse, bran); and to evaluate the effect of these fractions on rheology, and quality of GF bread. High fibre content (31.5%) and good hydration and functional properties demonstrated the suitability of bran for food development. A mixture design with three components was used. Pasting parameters, bread specific volume (BSV), firmness and colour intensity (Chr) responses were fitted to linear and quadratic polynomial models. The presence of bran in the blends reduced almost all pasting parameters. The optimal mixture proportion was flour:coarse:bran (45:35:20), presenting a BSV 1.7 ± 0.1 cm³/g; firmness 0.23 ± 0.01 MPa, and Chr 23.8 ± 0.4. A portion (50 g) of GF bread increased four times the dietary fibre intake. The utilization of different rice fractions to formulate GF bread improved the product quality and enhance the nutritional profile.

Effects of chitosan oligosaccharide and hyriopsis cumingii polysaccharide on the quality of wheat flour and extruded flour products

Abstract

Effects of chitosan oligosaccharide (COS) and hyriopsis cumingii polysaccharide (HCP) on the quality of wheat flour and corresponding extruded flour products were investigated in this work. The results showed that both COS and HCP are conducive to the improvement of dough quality. Moreover, compared to control group samples, the moisture content, expansion ratio and oil absorption rate of the samples were increased and the hardness were decreased with the addition of COS. These phenomena indicate the quality of extruded flour products became better in the presence of COS as well. However, HCP has little or no effect on the quality of extruded flour products may be due to its degradation under high temperature and pressure extrusion. COS with higher stability exhibited better improvement effects on the quality of extruded flour products and showed a promising prospect for application in extruded food industry.

Graphical Abstract

Mechanical, sensory, and consumer evaluation of ketogenic, gluten-free breads

Ketogenic, gluten-free breads comprised of almond flour, oat bran fiber, or combinations of both were compared. The textural properties, sensory attributes, and consumer acceptance were analyzed on each bread containing 100% almond flour (AF), 66.7% almond flour with 33.3% oat bran fiber (AOB), 66.7% oat bran fiber with 33.3% almond flour (OBA), and 100% oat bran fiber (OB). AF and AOB breads had a more open crumb structure composed of cells between 1-4 mm2. OBA and OB had a significantly dense crumb pattern made up of more cells less than one millimeter squared. Quantitative-descriptive analysis (QDA) and consumer acceptance testing was conducted 24 hr after baking and mechanical endpoints were evaluated 24, 72, and 120 hr after baking. AF and AOB breads were preferred over OBA and OB breads in QDA evaluation and consumer acceptance scores. Greater percentages of oat bran fiber resulted in a bread that was less moist, firmer in texture, and chewier with trained panelists. In both sensory evaluations, higher amounts of almond flour resulted in higher values in eggy flavor while increased amounts of oat bran fiber correlated with higher values in earthy flavor. Mechanical testing identified higher percentages of almond flour resulted in bread that was less firm and less chewy. Over time, all variations with almond flour became softer and less chewy, while the OB bread increased in firmness. Sensory cohesiveness did not correlate with the mechanical equivalent, identifying a need to re-evaluate the parameters used to calculate this objective endpoint.

Effect of By-Products from Selected Fruits and Vegetables on Gluten-Free Dough Rheology and Bread Properties

The aim of the study was to investigate the effect of using various by-products (orange and apple pomace, tomato peel, pepper peel, prickly pear peel, and prickly pear seed peel) on the dough rheology and properties of gluten-free bread. The by-products were incorporated into a gluten-free bread formulation based on corn and chickpea flours (2/1 w/w). Different levels of each by-product (0, 2.5, 5, and 7.5% in the basic replacement) were tested. Wheat bread and gluten-free bread without the addition of by-products were used as controls. The results indicated that the by-products increased the maximum dough height, the total CO2 production, and CO2 retention coefficient compared to unenriched gluten-free dough. The highest K-value consistency coefficient was observed for the dough enriched with the prickly pear peel. The addition of by-products significantly improved (p < 0.0001) the specific volume of gluten-free bread, with values increasing from 1.48 to 2.50 cm3/g. The hierarchical cluster analysis and the constellation plot showed four groups: the wheat bread group, the second group containing the gluten-free control bread, the group with bread enriched by pomace, and the group with bread enriched with peels, exhibit the same effect on gluten-free bread and the peels exhibit the same effect on gluten-free bread.

Glycemic Index of Gluten-Free Bread and Their Main Ingredients: A Systematic Review and Meta-Analysis

This study aimed to perform a systematic review and meta-analysis of the glycemic index (GI) of gluten-free bread (GFB) and its main ingredients. The systematic review followed PRISMA guidelines, using seven electronic databases (PubMed, EMBASE, Scopus, Science Direct, Web of Science, gray literature research with Google Scholar, and patents with Google Patent tool), from inception to November 2020. Eighteen studies met the inclusion criteria evaluating 132 GFB samples. Five articles tested GI in vivo, eleven in vitro; and two studies tested both methods. The analysis showed that 60.7% (95% CI: 40.2-78.1%) of the samples presented high glycemic indexes, evidencing a high glycemic profile for GFB. Only 18.2% (95% CI: 11.7-27.2%) of the bread samples presented in the studies were classified as a low GI. Meta-analysis presented moderate/low heterogenicity between studies (I2 = 61% and <1% for both high and low GIs) and reinforced the proportion of high GIs. Lower GIs were found in formulations based on Colocasia esculenta flour or enriched with fiber, yogurt and curd cheese, sourdough, psyllium, hydrocolloids, enzymes, fructans, and resistant starch, highlighting the efficacy of these ingredients to lower GFBs' GI. GFB tends to present high GI, impacting the development of chronic diseases when consumed.

Effects of psyllium seed husk powder, methylcellulose, pregelatinised starch, and cold water swelling starch on the production of gluten free crackers

Psyllium seed husk powder and pregelatinised starch crackers had comparable textural properties and sound release to wheat crackers, while the functionality of methylcellulose was limited due to low moisture addition.

Effects of ascorbic acid and sugar on physical, textural and sensory properties of composite breads

The present study was carried out to demonstrate the combined effects of different maize flour, ascorbic acid and sugar on the physical, textural and sensory properties of composite breads. The composite flour was prepared using 70% of wheat flour and 30% of flour obtained from grain of differently colored maize - light blue, blue, red and yellow maize flour. Chemical characterization of composite flours made with four different types of maize was also assessed. Furthermore, the content of total phenolics, flavonoids, anthocyanins, phenolic acids and antioxidant capacity in composite flours was determined. A total of 12 breads were prepared, four of which were control composite breads, four breads with ascorbic acid, and four were breads with ascorbic acid and sugar. The content of total phenolic compounds showed clear differences among all composite flours. The anthocyanins content determined in composite flours was in the following descending order: blue>red>light blue, while in the yellow maize composite flour anthocyanins were not detected. The results showed that the addition of AsA (0.025%) and sugar (5%) negatively affected the volume as well as the specific volume of composite wheat-maize breads. The texture analysis showed that the addition of AsA in the amount of 0.025% had no impact on springiness, cohesiveness and resilience of bread crumb, while it increased crumb hardness. However, composite breads made with AsA and AsA/sugar showed a more compact structure, with a larger number of cells and smaller mean cell areas. AsA/sugar bread samples within the tested doses had the lowest springiness, which is indicative of brittleness and reflects the tendency of the bread to crumble when slicing. Results of the sensory evaluation revealed that the AsA and sugar addition had a generally positive effect on the investigated sensory attributes.

Effect of Addition of Green Coffee Parchment on Structural, Qualitative and Chemical Properties of Gluten-Free Bread

Green coffee parchment (GCP) is becoming interesting, due to the diffusion of wet processing in which coffee parchment is collected separately; it is one of the less studied coffee by-products, but it is reported to be rich in phenolic compounds and dietary fiber. The addition of GCP (355–500 μm) at 2% to gluten-free breads was investigated in terms of physical properties (volume, moisture content, water activity, crumb grain, texture, and color), total antioxidant capacity (TAC) and total phenol content during three days of storage. Moreover, the effects of GCP on sensorial characteristics, 5-hydroxymethylfurfural (HMF), and oxidative stability was evaluated. From the sensorial analysis, bread with 2% addition resulted in being acceptable for consumers with no significant differences from the control, while 4% of GCP was discarded by consumers, as it resulted in being too bitter. Moreover, GCP at 2% addition did not modify volume, moisture content, and water activity. On the contrary, GCP deeply affected the color with a darker aspect that was appreciated by consumers. Regarding texture, 2% of GCP did not affect hardness, cohesiveness, and staling process during storage. Interestingly, 2% of GCP significantly improved the TAC and oxidative stability of the bread; in accordance with these results, 2% of GCP reduced the HMF content, thanks to its antioxidant compounds.

Characterization of Bitter and Astringent Off-Taste Compounds in Potato Fibers

Applying the sensomics approach, a combination of activity-guided fractionation and taste dilution analysis (TDA) followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), ultrahigh-performance liquid chromatography time-of-flight mass spectrometry (UHPLC-TOF-MS), and one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy (1D/2D NMR) allowed the elucidation of key off-taste compounds in potato dietary fiber isolates. Previously already having been described as off-taste compounds in potato tubers, saponins α-chaconine and α-solanine were shown to be also major contributors to overall off-taste in potato fiber isolates. Moreover, fatty acids as well as fatty acid oxidation products, namely, E-9,10,13-trihydroxy-octadec-11-enoic acid as well as newly identified compounds hexadecyl(E/Z)-ferulate and octadecyl(E/Z)-ferulate, were shown to be key inducers to off-taste in the isolates, exhibiting taste recognition thresholds between 18 and 981 μmol/L. This paper demonstrates the isolation, structure determination, quantitation as well as sensory attributes of these key off-taste compounds.

The evaluation of part-baked frozen bread produced from wheat flour and guar gum in the diet of celiac patients

The present study evaluated an enzyme strategy for eliminating the gliadin in the flour in order to produce part-baked (PB) frozen bread for celiac patients. At first, tissue transglutaminase with lysine methyl ester transamidated the gliadin and hydrolyses gliadin protein. The deamidated dough was used for producing the PB bread and then stored as the frozen storage at - 18 °C for 15 days, followed by investigating physicochemical, rheological, and sensory properties. The SDS-PAGE result demonstrated that transamidating wheat flour with a tissue transglutaminase and L-lysine methyl ester break down the gliadin protein. The PB frozen bread with the absence of gliadin had lower specific volume, porosity, firmness, and color index (P < 0.05) but adding 0.8% guar gum could improve these factors and recompense the absence of gliadin (P < 0.05). The PB frozen bread with 0.8% guar gum had physicochemical properties such as fresh bread which produced with untreated wheat flour (P < 0.05).

Effects of corn distillers dried grains on dough properties and quality of Chinese steamed bread

Chinese steamed bread (CSB) accounts for 30% of the wheat end-use in China. CSB was studied as a platform for fiber and protein enrichment, employing corn distillers dried grains. Food grade distiller's grain (FDDG) processed from co-products from the corn ethanol industry was used as the enrichment ingredient. Since CSB uses a lean formula with little or no added sugar or fat, it relies entirely on fermentation and steaming for flavor and texture development. FDDG was used to replace 0%-25% all-purpose flour (APF) in CSB formulations. Effects of FDDG on dough properties and quality of CSB were evaluated by instrumental (Farinograph, Mixolab, and Texture Analyzer), nutritional, and sensory methods. Protein and dietary fiber contents showed significant increases to 18.8% and 15.3%, respectively, for 100 g of steamed bread (25% FDDG db). Fiber in 100 g of fresh FDDG CSB ranged from 2.8 to 7.7 g. FDDG fortified doughs demonstrated higher water absorption, while dough development time, dough stability, and dough extensibility decreased significantly with partial APF replacement. FDDG contributed to increased hardness and adhesiveness in the CSB. Crumb analysis revealed reduced number of gas cells at higher FDDG substitution. FDDG enrichment reduced brightness (L*) of flour blends and CSB. Rheological and sensory analysis showed an upper level of FDDG substitution of 15% was acceptable without detriment to dough functionality, texture, and taste.

Chemical Composition and Glycemic Index of Gluten-Free Bread Commercialized in Brazil

Nowadays, the world is experiencing an increased demand for gluten-free products associated with the high prevalence of gluten-related disorders (GRD). As this market thrives, bread stands out as the most demanded and consumed product, highlighting the need to evaluate its nutritional quality. In this sense, this cross-sectional study aimed to assess the ingredients, chemical composition, and glycemic index of gluten-free bread (GFB) commercialized nationwide in Brazil. The labels were analyzed according to their ingredients and composition. In addition, centesimal composition analysis (moisture, carbohydrates, protein, ash, lipid, and fiber) was performed using the official methods, as well as the in vivo glycemic index. Significant differences between manufacturing lots of each brand and between different gluten-free bread samples were found. There is a mismatch from what is stipulated by the Brazilian legislation between analytical data and the data described on sample labels. Samples showed predominantly refined starch and high glycemic index profile. Most samples (75%, n = 6) of the non-whole gluten-free bread (n = 8) presented high glycemic index (GI). From four whole food/multigrain gluten-free bread samples, three of them (75%) presented medium GI. However, two samples presented GI near the value to be considered high. The results suggest a lack of production control, impairing the gluten-free nutritional label as a reliable information source and tool for dietary control. Therefore, it is necessary to standardize the process of gluten-free bread production and labeling, as well as to improve the nutritional characteristics of these products, aiming the give accurate information to consumers and provide a healthier product beyond the sensory characteristics.