Rheological properties of water insoluble date fiber incorporated wheat flour dough

Role of superfine grinding in whole-purple-wheat flour. Part II: Impacts of size reduction on dough properties, bread quality and in vitro starch digestion

This study aimed to enhance bread functionality while maintaining its organoleptic attributes by employing superfine grinding and purple wheat, through characterizing dough properties, bread quality attributes, and in vitro starch digestibility. Compared with dough made from commercial-superfine-whole-wheat flour, the superfine-whole-purple-wheat dough was less strong, comparably extensible, and higher in gassing power during mixing, moulding and proofing, respectively. The subsequent bread quality analysis of crumb grain features and texture indicated that the bread made from superfine-whole-purple-wheat flour was more porous and softer with a larger specific volume (3.21 ± 0.20 cm3/g) than that made from commercial-superfine-whole-wheat flour (2.30 ± 0.17 cm3/g). Additionally, the superfine-whole-purple-wheat bread had a significantly slower glucose release (k = 0.0048 min-1) during in vitro starch digestion as compared to the superfine-whole-wheat bread (k = 0.0065 min-1). Therefore, this study demonstrates that using superfine-whole-purple-wheat flour leads to bread with desirable quality attributes and potential health benefits compared to conventional whole-wheat flour.

Valorizing date seeds through ultrasonication to enhance quality attributes of dough and biscuit, Part-1: Effects on dough rheology and physical properties of biscuits

In the present study, non-conventional and green technology (ultrasonication) was utilized to recover bioactive compounds from the small, medium and large sized defatted date seed powder (DDSP) particles. Bioactive compounds recovered from DDSP and the remaining fiber-rich residue were incorporated as functional ingredient in the biscuit dough to enhance the functionality and the quality characteristics of the dough and biscuit. The polyphenolic extract and 2.5 %, 5 % and 7.5 % substitution levels of fiber-rich extraction residue were incorporated in formulations followed by investigating the effect on rheological, physical and microstructural properties of dough and biscuit. Loss and storage moduli, G'' and G', respectively, of dough increased with decreasing particle size and increasing substitution level while tan δ decreased with increasing substitution level of fiber-rich extraction residue. The smallest particles at 7.5 % substitution level resulted in the lowest creep strain value in dough. Hardness of the dough and biscuit increased with decreasing particle size and increasing substitution level of the residue. The 7.5 % substitution level of the smallest particle size resulted in the darkest dough and biscuit. Spread ratio and diameter of the biscuit decreased with increasing substitution level of the residue. The smallest diameter of 50.61 mm and spread ratio of 8.36 was observed in the biscuits substituted with the largest particle size with 7.5 % substitution level. Microstructural images of dough and biscuit revealed that the continuity of the gluten network was disrupted by the incorporation of the fiber-rich extraction residue. This study provided valuable insights into extracting bioactive components from date by-products using green ultrasonication technique and utilizing such compounds to improve functional attributes of bakery products, as a sustainable approach for valorizing date by-products.

Effects of four kinds of improver on fermentation characteristics of gluten-free rice dough

Rice is commonly utilized as a wheat bread substitute due to its low allergenicity. However, rice bread faces challenges in processing efficiency and the formation of a cohesive gel network structure, resulting in suboptimal taste Hence, this study compared four improvers-trypsin, whey protein (WPC), hydroxypropyl methyl cellulose (HPMC), and molecularly distilled monoglycerides (GMSs). The impacts of the four improvers on the processing attributes of rice dough were comprehensively assessed across fermentation, moisture content analysis, rheology, heat stability, and pasting characteristics. The findings indicated that the incorporation of trypsin, HPMC, and WPC resulted in 107%, 61%, and 1% increases in gas production of fermented rice dough, respectively, while reducing the regrowth values to 564.00 ± 7.21, 176.67 ± 0.58, and 611.00 ± 3.61 cP. Notably, the air-holding capacity of HPMC-fermented rice dough exhibited a 7% enhancement. All four types of improvers raised the enthalpy of melting (ΔH) and the difference in melting point (ΔT) of fermented rice doughs, with trypsin enhancing ΔH by 44% and ΔT by 40%. GMS, HPMC, and WPC increased the degree of water incorporation in fermented doughs. This study could serve as a benchmark for enhancing the fermentation attributes of rice dough and establish a groundwork for the future advancement of gluten-free dietary options. PRACTICAL APPLICATION: The thorough analysis conducted in this experiment provides a theoretical framework for rice dough preparation during the fermentation process, addressing the dietary needs of individuals with coeliac disease and those following a gluten-free diet. This study also paves the way for the development of improved gluten-free rice products in future research pursuits.

Watermelon Rind Dietary Fibers as Natural Source to Enhance Texture of Wheat Bread

The objective of this study was to explore how watermelon rinds (WMRs) and their derivatives, specifically water-soluble polysaccharides (WMRPs) and hemicellulose (WMRH), as sources of dietary fiber, could enhance the quality of wheat bread. The extraction process yielded 34.4% for WMRP and 8.22% for WMRH. WMR, WMRP, and WMRH exhibited promising functional characteristics and were incorporated separately into wheat flour with low bread-making quality (FLBM) at varying proportions (0.5%, 1%, and 1.5% (w/w)). The volume, texture, and crust and crumb color underwent evaluation and were compared to the control. The findings indicated that incorporating WMR notably enhanced the alveograph profile of the dough, demonstrating a more effective impact than the addition of WMRP and WMRH. Adding WMR, WMRP, and WMRH at a 1% concentration to low-quality wheat flour for bread making increased the deformation work values by 16%, 15%, and 13%, respectively, and raised the P/L ratios by 42%, 36%, and 38%, respectively. Additionally, the assessment of the bread highlighted a substantial enhancement in both volume and texture profile when WMR was added, in contrast to the control bread (made with FLBM). These findings underscore that incorporating 1% WMR into FLBM was the most effective means of improving bread quality based on the results of this study.

Effect of goji berry incorporation on the texture, physicochemical, and sensory properties of wheat bread

The regular intake of Lycium barbarum (goji berry) is supposed to play an important role in the promotion of human health. Regarding, its incorporation into staple foods, including bread, seems to be effective. However, it requires the evaluation of dough behavior and final product quality. This study investigated the effect of goji berry incorporation at levels of 10, 15, 20, 25, and 30% ww-1 on the textural, physicochemical, and sensory properties of wheat bread. Results indicated a significant enhancement of water absorption and gelatinization temperature in composite flour via the inclusion of goji berry powder (p < 0.05). Using goji berry powder up to 20% ww-1 has shown to obtain the structure able to restore gases through the baking process and provide enhancement in a specific volume at about 10%. Alongside, the hardness of composite bread decreased, and the optimal hardness was observed at formulations containing 20% w/w goji berry powder with a value equal to 1199.95 ± 0.05 g, which is supposed to be induced by the higher specific volume and lower moisture content of bread samples. Moreover, color and sensory perception have been found to be significantly changed by goji berry substitution. Goji berry substitution up to 20% ww-1 is found to be preferred by the consumer, and a drop in overall acceptability was observed at its higher inclusion. The technological characteristic changes induced by goji berry incorporation are induced by its gluten dilution impact. However, the gel-like structure formed by the high fiber content of goji berries compensates for this adverse impact up to 20% w/w substitution level.

Effects of Artemisia dracunculus powder on dough rheology and quality properties as a novel ingredient in bread formulation

Tarragon has a great potential to be a healthy functional food ingredient thanks to its rich antioxidant, phenolic compounds, and nutrient content. The possibility of enriching bread with tarragon was investigated. For this aim, tarragon powder was used at the rates of 0, 2, 4 and 6% instead of wheat flour. In this study, the effects of substitution on the rheological properties of bread dough and color, total phenolic content, antioxidant activity, texture, sensory, and Fourier transform infrared (FT-IR) analysis of bread samples were performed. The composition of tarragon powder showed significant protein (23.16%), crude fiber (7.4%), antioxidant (48.22 ± 0.11%), and total phenolic content (511.66 ± 1.56 mg GAE/100 g). Bread samples with increased fiber and protein content were obtained by adding tarragon powder to the bread formulation. The major differences in the FT-IR absorbance spectra for the bread samples were not observed. Additionally, tarragon powder significantly increased the antioxidative properties of breads (p < 0.05). Adding up to 4% tarragon powder to the bread formulation increased the sensory scores of the breads.

Rhubarb powder: Potential uses as a functional bread ingredient

As a traditional staple food, bread lacks several nutrients such as fiber and minerals. In this study, the possibilities of using rhubarb powder to enrich wheat bread were investigated. Rhubarb powder was replaced with wheat flour at the ratios of 0%, 4%, 8%, and 12%. In order to reveal effects of rhubarb powder on quality properties of bread, color, moisture, total protein, fat content, antioxidant activity, textural, and sensory analysis were conducted. As the rhubarb powder ratio increased, the fiber (10.60 ± 0.55), ash (4.34 ± 0.13), and fat content (2.17 ± 0.55) of bread samples increased significantly (p < 0.05). Antioxidant activity (19.61% ± 0.53%) and total phenolic contents (916.38 ± 2.69) of bread samples also increased significantly (p < 0.05). The colors of the enriched breads were relatively dark. The breads containing 12% rhubarb powder had the highest ash content (4.34 ± 0.13). The samples containing 4% rhubarb powder took the highest sensory scores from the sensory panel in terms of odor, flavor, and overall impression. However, as the ratio of rhubarb powder increased, the sensory values of bread samples decreased. According to the results of this study, rhubarb powder could be used up to 4% to produce acceptable breads in terms of sensory properties with improved nutritional quality.

Influence of roasted flaxseed marc flour on rheological, structural, fermentation, water distribution, and migration properties of wheat dough

Roasted flaxseed (RF) marc, which is a by-product obtained from RF oil extraction, has high nutritional value. This study evaluated the impact of RF marc flour on rheological, structural, fermentation, water distribution, and migration properties of the wheat dough. Results showed that adding RF into wheat flour (WF) could effectively increase the water absorption in the dough and retard the retrogradation of starch. The fermentation results revealed that adding RF could improve the gas retention coefficient of dough. Compared to the dough prepared with WF, the doughs enriched with RF had higher tan δ values (ratio of loss modulus G″ to storage modulus G'), indicating a more liquid-like property. The mobility of tightly bound and free water in dough was decreased by adding RF, whereas the distribution of free water was increased. On the one hand, adding RF would dilute the gluten content in dough, resulting in a weaker protein network. On the other hand, the dietary fiber and proteins in RF could offset the gluten dilution effect to some extent. Overall, the results suggested that the substitution level of RF in WF should be below 25% to avoid serious dough quality deterioration, and the RF-WF blended flour could be a potential ingredient to produce wheat products with moist taste. These findings could be useful for guiding the future usage of RF marc in wheat-based products.

Effect of Adding Fermented Proso Millet Bran Dietary Fiber on Micro-Structural, Physicochemical, and Digestive Properties of Gluten-Free Proso Millet-Based Dough and Cake

The increasing demand for functional foods has pushed the food industry to produce fiber-enriched products. In this study, rheological, microstructural, physicochemical, and functional characteristics were investigated for whole proso millet dough and cake, fortified with fermented proso millet bran dietary fiber flour (F-DF). Results showed that proso millet flour is less absorbent and stable than the control group. Adding proso millet flour and F-DF reduced the elasticity of the dough and increased its hardness, but had no significant effect on viscosity, cohesion, and resilience. The microstructure analysis exhibited an unformed continuous network formation in proso millet dough. Analyses suggested that proso millet flour combined with the fermented dietary fiber group had significantly higher total phenol content (0.46 GAE mg/g), DPPH• scavenging activity (66.84%), and ABTS•+ scavenging activity (87.01%) than did the other group. In addition, F-DF led to a significant reduction in the predicted released glucose contents of reformulated cakes. In summary, cakes prepared with the involvement of whole proso millet flour and F-DF exhibited less adverse sensory impact and possessed the potential to decrease postprandial blood glucose levels resulting purely from cake consumption.

Physicochemical, Antioxidant, Sensory, and Starch Digestibility Properties of Steamed Bread Fortified with Tamarillo Powder

The effects of lyophilized tamarillo powder (TP) on the physicochemical, antioxidant, sensory, and starch digestibility characteristics of steamed breads were studied. The TP was used to substitute 5-20% of wheat flour to make steamed breads, assigned as T5, T10, T15, and T20, respectively. The results showed that TP is rich in dietary fiber (36.45%). Its extract is rich in bioactive components, including phenolic compounds (28.90 mg GAE/g extract), ascorbic acid (3.25 mg/g extract), total anthocyanins (316.35 μg C3GE/g extract), and total carotenoids (12.68 μg βCE/g extract) and has good antioxidant capacity. As the level of TP increased, the color of steamed breads became darker, redder, and yellower; the texture became harder, and the overall consumption preference decreased. However, their bioactive components content and antioxidant activity increased. The starch hydrolysis percentage of T5 (43.82%), T10 (41.57%), T15 (37.41%), and T20 (35.63%) at 180 min was significantly lower than that of the control (49.80%) (p < 0.05). The in vitro predicted glycemic index (80.02) of T20 was categorized as a medium-GI food when bread was used as the reference. On a nine-point hedonic test, control and T5 had the highest overall preference scores (7.1-7.4). The T20 supplemented with extra 15-20% water improved its volume and specific volume, and the overall preference scores (7.4-7.5) were not significantly different from the control (p > 0.05). Overall, a partial replacement of wheat flour with TP in steamed bread making could be developed as a new type of medium-GI value food containing more bioactive components and effective antioxidant capacity.

Effect of multiple-frequency ultrasound-assisted transglutaminase dual modification on the structural, functional characteristics and application of Qingke protein

Qingke protein rich in restricted amino acids such as lysine, while the uncoordination of ratio of glutenin and gliadin in Qingke protein has a negative impact on its processing properties. In this study, the effect of multiple-frequency ultrasound combined with transglutaminase treatment on the functional and structural properties of Qingke protein and its application in noodle manufacture were investigated. The results showed that compared with the control, ultrasound-assisted transglutaminase dual modification significantly increased the water and oil holding capacity, apparent viscosity, foaming ability, and emulsifying activity index of Qingke protein, which exhibited a higher storage modulus G' (P < 0.05). Meanwhile, ultrasound combined with transglutaminase treatment enhanced the cross-linking degree of Qingke protein (P < 0.05), as shown by decreased free amino group and free sulfhydryl group contents, and increased disulfide bond content. Moreover, after the ultrasound-assisted transglutaminase dual modification treatment, the fluorescence intensity, the contents of α-helix and random coil in the secondary structure of Qingke protein significantly decreased, while the β-sheet content increased (P < 0.05) compared with control. SDS-PAGE results showed that the bands of Qingke protein treated by ultrasound combined with transglutaminase became unclear. Furthermore, the quality of Qingke noodles made with Qingke powder (140 g/kg dual modified Qingke protein mixed with 860 g/kg extracted Qingke starch) and wheat gluten 60-70 g/kg was similar to that of wheat noodles. In summary, multiple-frequency ultrasound combined with transglutaminase dual modification can significantly improve the physicochemical properties of Qingke protein and the modified Qingke proteins can be used as novel ingredients for Qingke noodles.

Enrichment of Wheat Bread with Platycodon grandiflorus Root (PGR) Flour: Rheological Properties and Microstructure of Dough and Physicochemical Characterization of Bread

Platycodon grandiflorus (Jacq.) A.DC. root (PGR) flour is well known for its medical and edible values. In order to develop nutritionally fortified products, breads were prepared using wheat flour, partially replaced with PGR flour. The rheological properties and microstructure of dough and the physicochemical characterization of bread were investigated. Results showed that lower level of PGR addition (3 and 6 g/100 g) would improve the baking performance of breads, while the higher level of PGR addition (9 g/100 g) led to smaller specific volume (3.78 mL/g), increased hardness (7.5 ± 1.35 N), and unpalatable mouthfeel (21.8% of resilience and 92.6% of springiness) since its negative effect on the viscoelasticity and microstructure of dough. Moreover, sensory evaluation analysis also showed that the PGR3 and PGR6 breads exhibited a similar flavor to the control bread, but the 9 g/100 g addition of PGR provided bread with an unpleasant odor through its richer volatile components. As expected, the phenolic content and antioxidant capacity of bread increased significantly (p < 0.05) as PGR flour was added to the bread formulation. The total phenolic content (TPC) ranged from 14.23 to 22.36 g GAE/g; thus, DPPH• and ABTS•+ scavenging capacity increased from 10.44 and 10.06 μg Trolox/g to 14.69 and 15.12 μg Trolox/g, respectively. Therefore, our findings emphasized the feasibility of PGR flour partially replacing wheat flour in bread-making systems.

Comparative study of physicochemical, nutritional, phytochemical, and sensory properties of bread with plantain and soy flours partly replacing wheat flour

Plantain flour (PLF) and soy flour (SF) were used to substitute wheat flour (10% and 20% w/w) in composite bread. Physicochemical, phytochemical, and sensory properties were investigated. Partial substitution by PLF significantly increased (p < .05) starch, amylose, ascorbic acid, and potassium content in bread samples. In contrast, a significant improvement (p < .05) in protein, fat, amylopectin, and calcium content was observed with SF substitution. Composite bread with PLF and SF together lowered the hydrolysis index (HI) and glycemic index (GI) as compared with whole wheat flour. The molar phytate to minerals (iron, zinc, and calcium) ratio in all composite loaves was lower than reported critical values, except for phytate to iron. Significant differences (p < .05) were found in color, specific volume, and texture characteristics of loaves made from partial substitution with PLF and SF. Sensory evaluation revealed that bread with 10% PLF exhibited better scores for appearance and willingness to pay than the control. In contrast, SF negatively affected (p < .05) the appearance, texture, color, overall acceptance, and willingness to pay. The trade-off analysis indicated that PLF can be utilized to produce bread that meets consumers' demands, while incorporating SF as an alternative high-nutrient density bread will be beneficial to health.

Effect of Highland Barley on Rheological Properties, Textural Properties and Starch Digestibility of Chinese Steamed Bread

Highland barley has a different composition and structure to other crops. It has higher contents of total polyphenol (TPC), total flavonoid (TFC) and β-glucan, which can be supplemented to improve the nutrition of wheat-flour-based food. In this study, the flours of three different grain-colored highland barley varieties Beiqing 6 (BQ), Dulihuang (DLH), and Heilaoya (HLY), were added to Jimai60 (JM, a wheat variety with medium gluten) wheat flour at different substitution levels to investigate their effects on the unextractable polymeric protein (UPP) content, micro-structure, rheological properties and mixing properties of dough, and the color, texture, flavor, and in vitro digestion of Chinese steam bread (CSB). The results showed that the moderate substitution of highland barley (20%) increased the UPP%, optimized the micro-structure of gluten, and improved its rheological properties by increasing dough viscoelasticity. The CSBs made from the composite flours exhibited a similar specific volume, cohesiveness, springiness and resilience to wheat CSB, while the firmness of composite CSBs (particularly JM-HLY-20) was delayed during storage. Importantly, the addition of highland barley increased the contents of TPC, TFC and β-glucan, but decreased the in vitro starch digestibility of CSBs. A sensory evaluation showed that JM-HLY CSB was the most preferable. Taken together, highland barley can be used as a fine supplement to food products, with health-promoting properties.

Effect of Extrusion Temperature and Feed Moisture Content on the Microstructural Properties of Rice-Flour Pellets and Their Impact on the Expanded Product

Extrusion can lead to an expanded product or to a slightly expanded pellet, known as a third-generation (3G) snack. In this case, expansion occurs subsequently, in an independent thermal device (e.g., oven), out of the extruded pellet. During both processes, several structural changes occur which are linked to processing conditions, including cooking temperature, screw speed, formulation, and initial moisture content. However, a clear relationship between processing variables and the structure of pellets and expanded products has not yet been identified. Accordingly, this work aimed to study the effect of extrusion temperature (110, 135, and 150 °C) and moisture content (27, 29, and 31%) in rice-flour pellets and their microwave expansion, through a microstructural approach using micro-CT. The results showed that the lowest moisture content (27%) and the highest extrusion temperature (150 °C) led to the highest pellet volume and the highest wall thickness, which in turn led to the highest expansion after microwave heating (50 s, 800 W). Interestingly, no significant differences were observed when analyzing the ratio between the volume of the expanded products and the volume of the pellet (~2.4) when using the different processing conditions.

Date Components as Promising Plant-Based Materials to Be Incorporated into Baked Goods—A Review

Date (Phoenix dactylifera L. Arecaceae) fruits and their by-products are rich in nutrients. The health benefits of dates and their incorporation into value-added products have been widely studied. The date-processing industry faces a significant sustainability challenge as more than 10% (w/w) of the production is discarded as waste or by-products. Currently, food scientists are focusing on bakery product fortification with functional food ingredients due to the high demand for nutritious food with more convenience. Utilizing date components in value-added bakery products is a trending research area with increasing attention. Studies where the researchers tried to improve the quality of bakery goods by incorporating date components have shown positive results, with several drawbacks that need attention and further research. The objective of this review is to present a comprehensive overview of the utilization of date components in bakery products and to identify gaps in the current knowledge. This review will help focus further research in the area of valorization of date by-products and thereby contribute to the generation of novel functional bakery products that meet consumer expectations and industry standards, thus generating income for the relevant industry and considerable alleviation of the environmental burden this waste and by-products contribute to. Only a few studies have been focused on utilizing date by-products and their extracts for baked goods, while a research area still remaining under-explored is the effect of incorporation of date components on the shelf life of bakery products.

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.

Dietary Fiber: Fractionation, Characterization and Potential Sources from Defatted Oilseeds

Dietary fiber (DF) has wide applications, especially in the food and pharmaceutical industries due to its health-promoting effects and potential techno-functional properties in developing functional food products. There is a growing interest in studies related to DF; nevertheless, there is less focus on the fractionation and characterization of DF. The characteristics of DF fractions explain their functionality in food products and provide clues to their physiological effects in food and pharmaceutical industrial applications. The review focuses on a brief introduction to DF and methods for its fractionation. It discusses the characterization of DF in terms of structural, physicochemical and rheological properties. The potential sources of DF from selected defatted oilseeds for future studies are highlighted.

Carboxymethylcellulose-induced changes in rheological properties and microstructure of wheat gluten proteins under different pH conditions

ABSRACT

The interaction between gluten and hydrocolloid additive, as well as the pH condition during dough formation is very important in making flour products. In this study, the influence of different pH conditions on the interactions between gluten proteins (including glutenin and gliadin) and carboxymethylcellulose (CMC), and on the rheological and microstructure changes of gluten proteins was investigated. The dynamic frequency sweep indicated CMC-gluten displayed more solid-like behavior under alkaline conditions than that under acidic conditions. The creep-recovery experiment suggested acidic conditions were not conducive to maintain the elasticity of CMC-gluten. Microstructural changes of various glutens with CMC showed that a higher ratio of β-sheets was observed in the CMC-gluten and CMC-glutenin under alkaline conditions. Total free sulfhydryl contents and changes in tryptophan microenvironment showed glutenin played a key role in the G polymerization with the addition of CMC. Lower surface hydrophobicity of CMC-gluten was displayed under acidic conditions. Scanning electron microscopy images showed that neutral and alkaline conditions were conducive to the network structure formation of CMC-gluten and CMC-glutenin.

PRACTICAL APPLICATION

This study investigated the interaction of CMC with gluten, gluten, and gliadin under different pH conditions, providing a basis for expanding dough quality improvement, and extending the in-depth application of CMC in the food industry.

Wheat Bread Fortification by Grape Pomace Powder: Nutritional, Technological, Antioxidant, and Sensory Properties

Grape pomace powder (GPP), a by-product from the winemaking process, was used to substitute flour for wheat bread fortification within 0, 5, and 10 g/100 g. Rheological properties of control and fortified doughs, along with physicochemical and nutritional characteristics, antioxidant activity, and the sensory analysis of the obtained bread were considered. The GPP addition influenced the doughs' rheological properties by generating more tenacious and less extensible products. Concerning bread, pH values and volume of fortified products decreased as the GPP inclusion level increased in the recipe. Total phenolic compounds and the antioxidant capacity of bread samples, evaluated by FRAP (ferric reducing ability of plasma) and ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) assays, increased with GPP addition. Moreover, the GPP inclusion level raised the total dietary fiber content of bread. Regarding sensory evaluation, GPP fortification had a major impact on the acidity, the global flavor, the astringency, and the wine smell of bread samples without affecting the overall bread acceptability. The current results suggest that GPP could be an attractive ingredient used to obtain fortified bread, as it is a source of fiber and polyphenols with potentially positive effects on human health.

Date Seeds as a Natural Source of Dietary Fibers to Improve Texture and Sensory Properties of Wheat Bread

The aim of this work was to investigate the effect of date seed water-soluble polysaccharides (DSP) and hemicellulose (DSH) as dietary fiber sources in enhancing the wheat bread's quality. DSP and DSH were extracted from the three date seed varieties Deglet Nour, Ghars Souf, and Allig. The extraction yields ranged from 3.8% to 6.14% and from 13.29% to 18.8%, for DSP and DSH, respectively. DSP and DSH showed interesting functional properties and were incorporated at 0.5% and 0.75% (w/w) in wheat flour with low bread-making quality (FLBM). The results showed that the addition of 0.75% DSH significantly improved the alveograph profile of the dough, and in a more efficient way than that of DSP. Furthermore, bread evaluation revealed that the addition of DSH considerably improved the volume (by 24.22%) and the texture profile of bread (decrease of the hardness and chewiness by 41.54% and 33.81%, respectively), compared to control bread (prepared with FLBM). A sensory analysis showed that the better overall acceptability was found for bread supplemented with DSH. Results in this work demonstrate that hemicellulose fraction extracted from date seeds (DSH) and added with a level of 0.75% to FLBM represents the component that improved bread quality the best.

Physical and Dynamic Oscillatory Shear Properties of Gluten-Free Red Kidney Bean Batter and Cupcakes Affected by Rice Flour Addition

Red kidney bean (RKB) flour is a nutrient-rich ingredient with potential use in bakery products. The objective of this study was to investigate the viscoelastic properties and key quality parameters of a functional RKB flour in gluten-free cupcakes with different rice flour levels. A 10 g model batter was developed for analyzing the viscoelastic properties of RKB with rice incorporation, in a formula containing oil, liquid eggs, and water. Rice flour was added at five levels 0%, 5%, 10%, 15%, and 25% (w/w, g rice flour/100 g RKB flour). Rice flour increased RKB batter consistency, solid- and liquid-like viscoelastic behavior and revealed a heterogeneous structure, based on the sweep frequency test. Rice flour at the 25% level increased the shear modulus and activation energy of gelatinization, compared to 0% rice flour addition. Rice flour levels in the RKB batter decreased the inflection gelation temperature from 63 to 56 °C. In addition, the texture of RKB cupcakes with 25% rice flour were 46% softer, compared to the control. The scores from all sensory attributes of cupcakes increased with the addition of rice flour. Rice flour addition improved solid- and liquid-like behavior of the RKB batter and improved the cupcake’s macro-structural characteristics. Overall, 25% rice flour addition performed better than the lower levels. This study confirmed the potential of RKB as a functional ingredient and its improvement in cupcake application with the addition of rice flour.

Small and large strain rheology of gluten and gluten-starch doughs containing wheat bran dietary fiber

BACKGROUND

The small and large strain rheology of gluten (G) and gluten-starch (G + S) doughs containing wheat bran dietary fiber (WBDF) were investigated.

RESULTS

At the small strain stage, i.e. frequency and strain sweep tests, the doughs containing high WBDF concentration are more vulnerable and unstable, as indicated by the lower dough linear viscoelastic strain limit as well as the higher slope of elastic modulus. However, the elastic nature of doughs remarkably increased upon WBDF addition, indicating the reinforcement of the dough mechanical strength, which is also confirmed by the large strain test wherein the maximum strain significantly decreased from 4.37 to 1.82 for the G system and from 12.09 to 2.72 for the G + S system. The creep recovery test showed that WBDF induced the reduction in the strain of the doughs at a fixed stress, which may be related to the enhanced strain hardening capacity.

CONCLUSION

The addition of WBDF resulted in more brittle and unstable doughs with undesirable higher mechanical strength. The presence of starch greatly weakened the dough strength and led to inferior resistance to both small and large deformations. These findings confirmed the impairment of dough viscoelasticity upon addition of WBDF. © 2019 Society of Chemical Industry.

Whole-wheat flour particle size influences dough properties, bread structure and in vitro starch digestibility

Whole-wheat flour (WWF) particle size is critical to dough properties, bread quality, and in vitro starch digestibility of bread.

Functional polysaccharides of carob fruit: a review

Polysaccharides in carob fruit, including carob bean gum (also known as carob gum, locust bean gum) and carob fiber, are widely used in industries such as food, pharmaceuticals, paper, textile, oil well drilling and cosmetics. Carob bean gum is a galactomannan obtained from the seed endosperm of carob tree and the fiber is obtained by removing most of soluble carbohydrates in carob pulp by water extraction. Both the gum and fiber are beneficial to health for many diseases such as diabetes, bowel movements, heart disease and colon cancer. This article reviewed the composition, properties, food applications and health benefits of polysaccharides from carob fruit.