Combined effects of α-amylase, xylanase, and cellulase coproduced by Stachybotrys microspora on dough properties and bread quality as a bread improver.

This study aims to explore the feasibility of introducing, during the manufacture of bakery bread, an enzymatic cocktail coproduced by the fungus Stachybotrys microspora: α-amylases, xylanases and cellulases, using wheat bran as a nutrient source. Among the characteristics of the alveograph (dough tenacity "P" and dough extensibility "L"), the addition of a cocktail of enzymes at a concentration of 2 %, to weak wheat flour, has made it possible to significantly reduce its P/L ratio from 2.45 to 1.41. Furthermore, the use of enzyme cocktails at 2 %, 4 %, and 6 % concentrations increases the brown color of the bread crust. The great reduction in the rate of bread firmness, during storage over 5 days, was obtained in the presence of an enzyme cocktail in comparison with bread control (65.13 N for the control and 22.99 N, 23.24 N, and 18.24 N for bread enriched with enzyme cocktail at 2 %, 4 % and 6 % concentrations, respectively). In conclusion, the enzyme cocktail added can synergistically improve bread dough rheology and bread properties.

Effect of Microwave Treatment on Protease Activity, Dough Properties and Protein Quality in Sprouted Wheat.

In this study, the effects of microwave treatment on protease activity, dough properties and protein quality in sprouted wheat were investigated. Microwave treatment led to a significant (p < 0.05) reduction in protease activity in sprouted wheat. Proteases with a pH optimum of 4.4 (cysteine proteinases) were more susceptible to microwave heating, which contributed mostly to protease inactivation. Significant improvements (p < 0.05) in the dough properties and gluten quality of sprouted wheat were observed, which are probably attributable to the synergistic effectiveness of protease inactivation and heat-induced gluten cross-linking. After microwave treatment, the decrease in the solubility and extractability of protein in sprouted wheat indicated protein polymerization, which was induced by intermolecular disulfide bond cross-linking. The changes in gliadin were less pronounced due to the relatively low temperature of the microwave treatment. The cross-linking in sprouted wheat that occurred after microwave treatment seemed to mainly involve glutenin, especially B/C low-molecular-weight glutenin subunits (B/C-LMW-GSs) in the range of 30-50 kD.

The effects of adding various starches on the structures of restructured potato-based dough and the oil uptake of potato chips.

BACKGROUND: The material composition significantly influences the oil absorption and quality characteristics of fried food products. The oil absorption of restructured potato chips is highly dependent on the structural properties of the restructured potato-based dough produced prior to frying. In this study, three types of starch were added to modify the structure of restructured potato-based dough, allowing the production of potato chips with less oil absorption. RESULTS: Distinct differences were observed among the three types of starch in terms of amylose content, chain length distribution, swelling power, solubility, crystalline structure and pasting properties. The addition of wheat starch, corn starch and tapioca starch changed the rheological properties, water distribution and strength of the restructured dough. Importantly, adding wheat starch and corn starch significantly lowered the oil content of potato chips by 7.94% and 13.06%, respectively. The reduction in oil absorption by potato chips was attributed to the increased strength of the starchy gel network of the dough, a slower rate of water evaporation and a limitation of dough expansion during frying. CONCLUSION: Adding wheat starch or corn starch to restructured potato-based dough resulted in a decrease in the oil absorption of potato chips by creating a stronger starchy gel network in the dough. This study could guide the development of suitable material compositions, which are important for producing fried food products with lower oil content. © 2024 Society of Chemical Industry.

Impact of Variation in Amylose Content on Durum Wheat cv. Svevo Technological and Starch Properties.

Reserve starch, the main component of durum wheat semolina, is constituted of two glucan homopolymers (amylose and amylopectin) that differ in their chemical structure. Amylose is mainly a linear structure formed of α-1,4-linked glucose units, with a lower polymerization degree, whereas amylopectin is a highly branched structure of α-1,4-chains linked by α-1,6-bonds. Variation of the amylose/amylopectin ratio has a profound effect on the starch properties which may impact the wheat technological and nutritional characteristics and their possible use in the food and non-food sector. In this work a set of genotypes, with a range of amylose from 14.9 to 57.8%, derived from the durum wheat cv. Svevo was characterised at biochemical and rheological level and used to produce pasta to better understand the role of amylose content in a common genetic background. A negative correlation was observed between amylose content and semolina swelling power, starch peak viscosity, and pasta stickiness. A worsening of the firmness was observed in the low amylose pasta compared to the control (cv. Svevo), whereas no difference was highlighted in the high amylose samples. The resistant starch was higher in the high amylose (HA) pasta compared to the control and low amylose (LA) pasta. Noteworthy, the extent of starch digestion was reduced in the HA pasta while the LA genotypes offered a higher starch digestion, suggesting other possible applications.

Inherent molecular characteristics and effect of garlic polysaccharides on dough micro- and mesoscopic properties.

Directional control of the process of doughs with nutrition fortification is challenging. Thus, this study aimed to develop non-starch polysaccharides that can modify the quality of flour products. Polysaccharides were extracted from three different garlic cultivars, evaluated for physicochemical properties and used to enrich doughs for microstructure and mesoscopic characteristics analysis. We assessed the moisture distribution, texture characteristics, thermodynamic properties, dynamic viscoelastic properties, protein structure, microstructure and molecular interaction of the doughs and demonstrated a relatively high molecular weight, lower steric hindrance of molecular chains and higher cross-linking ability with the dough network in the supernatant polysaccharide from Yunnan single-clove-garlic (SGSOS) fraction. These features of SGSOS fraction improved the rheological, thermodynamic, texture characteristics, and water distribution of doughs. These findings provide information on the use of garlic polysaccharides during the processing and manufacturing of foods to enhance their processing adaptability and qualities.

Physical quality of gluten-free doughs and fresh pasta made of amaranth.

Pasta is one of the most consumed foods in the world. Therefore, the development and investigation of the quality parameters of fresh gluten-free pasta made from amaranth was the subject of this study. For this purpose, different doughs (amaranth flour: water 1:2, 1:4, 1:6, 1:8, 1:10) were heat-treated and sodium alginate (1.0 and 1.5%) was added. The pasta was produced by extrusion into a 0.1 M calcium L-lactate pentahydrate-containing bath. Both the dough and the pasta were examined. The doughs for its viscosity properties, water content, and color and the pasta for its firmness, color, water content, water absorption, cooking loss, and swelling index. The pasta was cooked for 5, 10, and 15 min for the cooking quality study. A higher alginate content of 1.5% and a higher proportion of amaranth flour resulted in a significant difference in color, water content, and shear-dependent viscosity of the dough (p < .001). It was also found that both doughs with amaranth flour-water content of 1:2 and 1:10 had significant effects on processing properties and pasta quality, especially on firmness, swelling index, and cooking loss. For the doughs with a 1:2 ratio, the high flour content resulted in very soft pasta, and for the doughs with a 1:10 ratio, the high-water content resulted in very firm pasta with a smooth, watery surface. Overall, cooking loss, swelling index, and water absorption were low for the pasta with 1.5% alginate. Even with cooking times of 15 min, the pasta retained its shape.

Germinated Bambara groundnut (Vigna subterranea) flour as an ingredient in wheat bread: Physicochemical, nutritional, and sensory properties of bread.

Wheat flour (WF) was substituted with germinated Bambara groundnut (Vigna subterranea) flour (GBF) at different proportions (5%, 10%, 15%, 20%, 25%, and 30%) and used in the preparation of bread. The dough mixing, pasting, and gelatinization properties of the blends were evaluated as well as the nutritional quality, in vitro starch digestibility, phytochemical constituents, antioxidant potential, color, texture, and sensory properties of breads. All the wheat dough containing GBF had higher water absorption capacity, gelatinization temperatures, dough development time, low peak, and setback viscosities. The composite breads had significantly higher dietary fiber, minerals, protein digestibility, corrected amino acid scores, resistant starch, slowly digestible starch, total phenolics, total flavonoids, and antioxidant activities and caused significant reduction in rapidly digestible starch content. The addition of up to 15% GBF had no significant impact on the specific volume of wheat bread. Substitution of WF with GBF influenced color and texture properties of bread. Wheat bread supplemented with 20% GBF had significantly higher scores in taste, aroma, and overall acceptability. This study demonstrated the potential of GBF as a functional ingredient in bread making. PRACTICAL APPLICATION: This study provides a suitable possibility of partial substitution of wheat flour with germinated Bambara groundnut, to develop functional and acceptable bread. The dough mixing and pasting results in this study would add to knowledge on the dough handling characteristics as there is limited information regarding the mixing properties of wheat dough with germinated Bambara groundnut.

Influence of High-Molecular-Weight Glutenin Subunit on Components and Multiscale Structure of Gluten and Dough Quality in Soft Wheat.

A set of high-molecular-weight glutenin subunit (HMW-GS) deletion lines were used to investigate the influences of HMW-GS on wheat gluten, and dough properties were investigated using a set of HMW-GS deletion lines. Results showed that HMW-GS deletion significantly decreased the dough stability time, as well as viscoelastic moduli (G' and G″), compared with the wild type, where the deletion of x-type HMW-GSs (Ax1d, Bx7d, and Dy12d) decreased more than y-type HMW-GSs (By8d and Dy12d). The deletion of HMW-GS significantly decreased HMW-GS contents and increased α-/γ-gliadin contents. A proteomic study showed that the HMW-GS deletion down-regulated the HMW-GS, ß-amylase, serpins, and protein disulfide isomerase and up-regulated the LMW-GS, α/γ-gliadin, and α-amylase inhibitor. Meanwhile, HMW-GS deletion significantly decreased contents of ß-turn and ß-sheet. In addition, less energetically stable disulfide conformations (trans-gauche-gauche and trans-gauche-trans) were abundant in HMW-GS deletion lines. Furthermore, analysis of five HMW-GSs based on amino acid sequences proved that Dx2 and Bx7 had a more stable structure, followed by Ax1, then Dy12, and finally By8.

A combined use of different functional additives for improvement of wheat flour quality for bread making.

BACKGROUND: Low-protein wheat flour can produce bread with poor texture and appearance, reducing its nutritional value and market appeal. This is a growing concern for both the food industry and consumers relying on wheat as a dietary staple. The present study evaluated the individual and combined effects of bacterial xylanase (BX), maltogenic α-amylase (MG), vital gluten (VG) and ascorbic acid (AA) with respect to improving weak flour properties for bread making. RESULTS: BX, VG and AA improved gluten Index (GI), whereas MG was employed for optimizing amylolytic-activity in flour. VG increased the water absorption (WA) capacity of flour and prolonged dough development time (DDT). The dough stability (DST) was increased by BX and VG. BX and MG decreased crumb firmness (CF) and showed anti-staling effect. All additives reduced bake loss, increased loaf volume (LV) and retained or improved sensory attributes of bread. However, MG at 60 mg kg-1 (MG60), BX at 30 mg kg-1 (BX30), VG at 5% (VG5) and AA at 50 mg kg-1 (AA50) were found to be the most suitable for evaluating in combinations. Ternary combinations of MG60, BX30, VG5 or AA50 imparted significantly (P < 0.05) positive impacts on GI, WA, DDT, DST, CF, LV and sensory attributes compared to control, individual and binary combinations. CONCLUSION: The PCA suggested that a combination of MG60 + VG5 was more similar to MG60 + BX30 + VG5, whereas, MG60 + BX30 and MG60 + AA50 were more related to MG60 + BX30 + AA50 combination, but all of these combinations showed the improvement in the characteristics compared to control flour. © 2023 Society of Chemical Industry.

Addition of Psathyrostachys huashanica HMW glutenin subunit expresses positive contribution to protein polymerization and gluten microstructure of receptor wheat.

Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs) is considered as a valuable wild germplasm for wheat improvement on account of its numerous outstanding traits. During this study, 7182-1Ns with higher quality was screened out, a series of experiments were conducted to clarify the reasons of quality improvement. The results indicated 7182-1Ns was carried a novel high-molecular-weight glutenin subunit (HMW-GS) from P. huashanica, designated as P. huashanica' subunit in wheat (HS), which changed the HMW-GS compositions, increased the proportion of glutenins in wheat gluten protein, accelerated the accumulation speed of unextractable polymeric protein (UPP) during grain development stage accelerated, and a denser microstructure of the gluten network was formed in the dough. Therefore, the current research provides important reference on effectively utilize 7182-1Ns as an intermediate germplasm for quality breeding improvement.

Impact of Native Form Oat ß-Glucan on the Physical and Starch Digestive Properties of Whole Oat Bread.

To investigate the effect of oat bran on bread quality and the mechanism of reducing the glycemic index (GI) of bread, wheat bran (10%, w/w, flour basis), oat bran (10%), and ß-glucan (0.858%) were individually added to determine the expansion of dough, the specific volume, texture, color, GI, starch digestion characteristics, and α-amylase inhibition rate of bread. The results showed that the incorporation of wheat bran and oat bran both reduced the final expanded volume of the dough, decreased the specific volume of the bread, and increased the bread hardness and crumb redness and greenness values as compared to the control wheat group. The above physical properties of bran-containing bread obviously deteriorated while the bread with ß-glucan did not change significantly (p < 0.05). The GI in vitro of bread was in the following order: control (94.40) > wheat bran (69.24) > ß-glucan (65.76) > oat bran (64.93). Correspondingly, the oat bran group had the highest content of slowly digestible starch (SDS), the ß-glucan group had the highest content of resistant starch (RS), and the control group had the highest content of rapidly digestible starch (RDS). For the wheat bran, oat bran, and ß-glucan group, their inhibition rates of α-amylase were 9.25%, 28.93%, and 23.7%, respectively. The ß-glucan reduced the bread GI and α-amylase activity by intertwining with starch to form a more stable gel network structure, which reduced the contact area between amylase and starch. Therefore, ß-glucan in oat bran might be a key component for reducing the GI of whole oat bread.

Chain Terminators and Glutathione Weaken Wheat Dough under Excess Nitrogen Input.

An excessive nitrogen (N) supply may weaken dough due to an imbalance between N and sulfur (S) in the grains. However, the mechanism underlying the weakening effect of excessive N supply has yet to be fully elucidated. In this study, we evaluated the effect of the N rate × S rate interaction on the ratio of N to S (N/S ratio), grain protein concentration, amount and composition of protein fractions, and dough properties of a bread wheat cultivar. The concentrations of glutathione and modified gliadins with an odd number of cysteine residues (potential chain terminators for glutenins) were also examined. The results revealed that the weakening effect of excess N input is closely associated with an increased gliadin/glutenin ratio, reduced low-molecular-weight glutenin subunit concentrations, and the degree of polymerization of glutenin. More importantly, we found that the increased concentrations of glutathione and chain terminators in grains are involved in the modification of the polymerization degree in glutenins.

Interaction of B-type starch with gluten skeleton improves wheat dough mixing properties by stabilizing gluten micro-structure.

Some recent studies have revealed individual and the combined interactions of gluten and starch affecting dough mixing properties. However, the combined influence of high-molecular-weight glutenin subunits (HMW-GS) and starch on dough mixing and rheological properties requires elucidation. Thus four recombinant inbred lines, SS 1, SS 2, ZZ 1 and ZZ 2, were selected based on their HMW-GSs compositions. Compared to ZZ 1 and ZZ 2, both SS 1 and SS 2 carried superior HMW-GS alleles, and exhibited extended dough development and stability time, indicating their significant dough mixing characteristics. The gluten skeleton of the wheat lines SS 2 and ZZ 2 with higher B-type starch proportions exhibited fewer breakages along with the rise of dough temperature during mixing. Higher content of B-type starch strengthens interaction between starch and gluten skeleton at the dough heating stage, suggesting a specific range of B-type starch proportion can improve dough mixing characteristics.

Interactions between Phenolic Acids, Proteins, and Carbohydrates-Influence on Dough and Bread Properties.

The understanding of interactions between proteins, carbohydrates, and phenolic compounds is becoming increasingly important in food science, as these interactions might significantly affect the functionality of foods. So far, research has focused predominantly on protein-phenolic or carbohydrate-phenolic interactions, separately, but these components might also form other combinations. In plant-based foods, all three components are highly abundant; phenolic acids are the most important phenolic compound subclass. However, their interactions and influences are not yet fully understood. Especially in cereal products, such as bread, being a nutritional basic in human nutrition, interactions of the mentioned compounds are possible and their characterization seems to be a worthwhile target, as the functionality of each of the components might be affected. This review presents the basics of such interactions, with special emphasis on ferulic acid, as the most abundant phenolic acid in nature, and tries to illustrate the possibility of ternary interactions with regard to dough and bread properties. One of the phenomena assigned to such interactions is so-called dry-baking, which is very often observed in rye bread.

Wheat Fusarium Protease Specificity and Effect on Dough Properties.

Fusarium infection is a worldwide agricultural problem of billion dollar proportions globally, and it has increasingly threatened entire regional food supplies. In addition to the toxin deoxynivalenol (DON), Fusarium species express digestive enzymes that degrade starch and protein, affecting the quality of infected grains, especially wheat processing performance which depends largely on gluten proteins. In this study, the impact of Fusarium protease on the functionality of Canada Western Red Spring (CWRS) wheat was assessed by adding Fusarium-damaged kernels (FDK) to a FDK-free base wheat sample. Digestion of beta-casein by extracts of flours, milled from sound and FDK-spiked wheat samples, demonstrated elevated cleavage in FDK-spiked flour extracts as follows: N-terminal to lysine (eight-fold), N- and C-terminal to isoleucine (four-fold and three-fold, respectively), N-terminal to tyrosine (three-fold) and C-terminal to arginine at P1' (five-fold). Comparison of abbreviated (45 min) and standard (135 min) extensigraph test results indicated that desirable increases in dough resistance to extension (Rmax) due to gluten re-polymerization after longer resting were partially to completely counteracted in FDK-spiked flours in a dose-dependent manner. Baking tests confirmed that while loaf volume is similar, proofed dough from FDK-spiked samples caused detectable loaf collapse at 3% FDK. Extensigraph Rmax and Fusarium protease levels were inversely related, and effected by both the extent and severity of infection. While the current FDK tolerances for grading Canadian wheat can effectively control protease damage, prevalence of deoxynivalenol (DON) weak- and non-producing Fusarium strains/species (e.g., F. avenaceum) in some growing regions must be considered to protect functionality if grading is solely based on DON content.

Impact of wheat bran micronization on dough properties and bread quality: Part I - Bran functionality and dough properties.

This study aimed to investigate the effect of wheat bran micronization on its functionality including physicochemical and antioxidant properties, and dough properties. Coarse bran (D50 = 362.3 ± 20.5 µm) was superfine ground to medium (D50 = 60.4 ± 10.1 µm) and superfine (D50 = 11.3 ± 2.6 µm) bran, accompanied with increasing specific surface area and breakdown of aleurone layers. Bran micronization increased its soluble dietary fibre content, ferulic acid liberation, and antioxidant properties including total polyphenol content, ABTS•+ and DPPH• scavenging activities, while decreased its water retention capacity and insoluble dietary fibre content. Moreover, bran micronization impacted dough rheological properties. The dough with superfine bran had higher water absorption and gelatinization temperature, peak viscosity, final viscosity and setback value, lower stability time, resistance to extension, and extensibility than the dough with coarse bran. This dough furthermore exhibited more solid-like properties characterized by decreased loss moduli and frequency dependence (n').

Pasting, thermo, and Mixolab thermomechanical properties of potato starch-wheat gluten composite systems.

This research investigated the viscosity, thermal, thermomechanical, and microstructural properties of potato starch-wheat gluten composite systems with different starch/gluten ratios under mechanical shear and heating conditions. Results showed that the peak, trough, and final viscosities increased with the increase in potato starch fraction. The breakdown and setback values of samples decreased with increasing gluten content, and the endothermic enthalpy showed a similar variation trend. The gelatinization temperature of the samples increased significantly as the gluten proportion increased. Morphological observation showed that the gluten protein was wrapped around potato starch granules and the starch granules have a diluting effect on gluten network. Moreover, gluten formed a water diffusion barrier out of the starch granules, this barrier effect and the competitive hydration between starch and gluten could primarily explain the delayed gelatinization temperatures.

Effect of heat treatment to sweet potato flour on dough properties and characteristics of sweet potato-wheat bread.

The effect of heat treatment at 90, 100, 110 and 120 ℃ for 20 min to sweet potato flour on dough properties and characteristics of sweet potato-wheat bread was investigated. The lightness (L*) and a* of sweet potato flour samples after heat treatment were increased, while the b* were decreased significantly, as well as the particle size, volume and area mean diameter ( p < 0.05). A slight change of the microstructures of sweet potato flour was observed, where the number of irregular granules increased as the temperature increased from 90 to 120 ℃. Compared with sweet potato flour samples without heat treatment and with heat treatment at 90, 100 and 120 ℃, the gelatinization temperature and enthalpy change of sweet potato flour at 110 ℃ were the lowest, which were 77.94 ℃ and 3.67 J/g, respectively ( p < 0.05). After heat treatment, gas retention of the dough with sweet potato flour increased significantly from 1199 ml without heat treatment to 1214 ml at 90 ℃ ( p < 0.05). In addition, specific loaf volume of sweet potato-wheat bread with sweet potato flour after heat treatment increased significantly, which was the largest at 90 ℃ (2.53 cm3/g) ( p < 0.05). Thus, heat treatment at 90 ℃ to sweet potato flour could be potentially used in wheat bread production.

Molecular Analysis of the Polymeric Glutenins with Gliadin-Like Characteristics That Were Produced by Acid Dispersion of Wheat Gluten.

We had earlier shown that the dispersion of wheat gluten in acetic acid solution conferred gliadin-like characteristics to the polymeric glutenins. To elucidate the molecular behavior of its polymeric glutenins, the characteristics of gluten powder prepared from dispersions with various types of acid were investigated in this study. Mixograph measurements showed that the acid-treated gluten powders, regardless of the type of acid, had dough properties markedly weakened in both resistance and elasticity properties, as though gliadin was supplemented. The polymeric glutenins extracted with 70% ethanol increased greatly in all acid-treated gluten powders. Size exclusion HPLC and SDS-PAGE indicated that the behavior of polymeric glutenins due to acid treatment was attributed to their subunit composition rich in high molecular weight glutenin subunit (HMW-GS) and not their molecular size. The gluten prepared with the addition of NaCl in acid dispersion had properties similar to those of the control gluten. The results suggest that ionic repulsion induced by acid dispersion made the polymeric glutenins rich in HMW-GS disaggregate, and therefore, act like gliadins.

Optimization of Aspergillus oryzae S2 α-amylase, ascorbic acid, and glucose oxidase combination for improved French and composite Ukrainian wheat dough properties and bread quality using a mixture design approach.

A simplex-centroid experimental design was used for the optimization of both reducing and oxidizing improvers, namely Aspergillus oryzae S2 α-amylase (Amy), ascorbic acid (Asc), and glucose oxidase (GOD). This optimization was performed to enhance the dough and breadmaking qualities of soft French wheat flour and a composite counterpart that contained 30% Ukrainian wheat flour. Statistically significant correlations were calculated between the W index and textural parameters (e.g., dough chewiness and bread cohesiveness). The findings revealed that while the best mixture for French flour comprised 21.8% of Amy, 41.2% of Asc, and 37% of GOD, for the composite counterpart, it comprised 2.3% of Amy, 66% of Asc, and 31.7% of GOD. These optimized mixtures rearranged soft French wheat flour and its composite counterpart to a good quality and an improved flour texture, respectively. Additionally, they increased the loaf specific volumes of the breads made from soft French wheat flour and its counterpart by 25.8 and 45.43%, respectively, significantly decreased the breads' susceptibility to microbial contamination, and reclassified the breads as "good" in terms of sensory attributes.