Effect of the addition of enzymes on the quality of frozen pre-baked French bread substituted with whole wheat flour

Extremophilic Prokaryotic Endoxylanases: Diversity, Applicability, and Molecular Insights

Extremophilic endoxylanases grabbed attention in recent years due to their applicability under harsh conditions of several industrial processes. Thermophilic, alkaliphilic, and acidophilic endoxylanases found their employability in bio-bleaching of paper pulp, bioconversion of lignocellulosic biomass into xylooligosaccharides, bioethanol production, and improving the nutritious value of bread and other bakery products. Xylanases obtained from extremophilic bacteria and archaea are considered better than fungal sources for several reasons. For example, enzymatic activity under broad pH and temperature range, low molecular weight, cellulase-free activity, and longer stability under extreme conditions of prokaryotic derived xylanases make them a good choice. In addition, a short life span, easy cultivation/harvesting methods, higher yield, and rapid DNA manipulations of bacterial and archaeal cells further reduces the overall cost of the product. This review focuses on the diversity of prokaryotic endoxylanases, their characteristics, and their functional attributes. Besides, the molecular mechanisms of their extreme behavior have also been presented here.

Effects of Different Amylose Contents of Foxtail Millet Flour Varieties on Textural Properties of Chinese Steamed Bread

In order to improve the nutritional value and quality of steamed bread, and promote the industrial development of the whole-grain food industry, a texture analyzer was used to study the effects of cultivars of whole foxtail millet flour (WFMF) on the texture of Chinese steamed bread (CSB). Orthogonal partial least squares discriminant analysis (OPLS-DA) was also conducted. The addition of different cultivars of WFMF significantly altered the height–diameter ratio, specific volume, hardness, cohesiveness, gumminess, and chewiness of CSB (p < 0.05). Large amounts of foxtail millet flour significantly increased the hardness, gumminess and chewiness of the bread (p < 0.05), and the bread height–diameter ratio, specific volume, cohesiveness and springiness significantly decreased (p < 0.05). We screened sensory evaluation, chewiness, specific volume, and hardness as the signature differences in the quality components according to the variable influence on the projection (VIP) values. OPLS-DA could distinguish the addition levels of different samples.

The Addition of α-cyclodextrin and γ-cyclodextrin Affect Quality of Dough and Prebaked Bread During Frozen Storage

The effects of the addition of 0–3.0 wt% α-cyclodextrin (α-CD) and γ-cyclodextrin (γ-CD) on the quality of wheat flour as well as the texture and the aging of prebaked bread were evaluated. The addition of α-CD and γ-CD increased the ability of wheat flour to absorb water and shortened the times of dough formation and stabilization. Amylase activity slightly increased after using 2.0 and 3.0 wt% of α-CD and γ-CD, respectively. Moreover, the addition of α-CD and γ-CD increased the fermentation height and gas retention ability of dough. Dough samples containing 2.0 wt% α-CD and 3.0 wt% γ-CD showed the highest fermentation heights and gas retention volumes, respectively. Dough gas production increased with the addition of γ-CD. Gas production by dough samples containing more than 2.0 wt% α-CD exceeded that by samples in the control group. The results of the texture crumb of bread and specific volume tests revealed that the addition of 2.0 wt% α-CD and 3.0 wt% γ-CD reduced bread hardness and increased bread elasticity, resilience, and specific volume. The optimal α-CD and γ-CD contents were identified as 2.0 wt% and 3.0 wt%, respectively. The addition of 2.0 wt% α-CD and 3.0 wt% γ-CD delayed the aging of prebaked bread and reduced the hardness of prebaked bread during different weeks of storage, which may be due to decreasing the melting enthalpy of starch crystals. This work elucidated the mechanisms underlying the effects of CD addition on prebaked bread quality.

The Effects of Amyloglucosidase, Glucose Oxidase and Hemicellulase Utilization on the Rheological Behaviour of Dough and Quality Characteristics of Bread

Wheat flour, whole wheat flour, 25 and 50 % rye flour substituted wheat flour blends, 15 and 30 % wheat bran substituted wheat flour blends were supplemented with amyloglucosidase (at 0.000875 and 0.001 %), glucose oxidase (at 0.0003 and 0.001 %) and hemicellulase (at 0.001 and 0.005 %). The effects of enzymes on the extensographic properties of dough and quality characteristics of bread (specific volume, baking loss percentage and final moisture content) were studied. The interaction between type of flour/blend, type of enzyme and dosage of enzyme affected resistance to extension, extensibility and ratio of resistance to extensibility of doughs significantly. The interactions between type of flour/blend, type of enzyme and dosage of enzyme affected specific volume, baking loss percentage and final moisture content of breads significantly. The findings in this study indicated that enzymes can exhibit unexpected effects on dough and bread properties depending on type of flour and dosage of enzyme.

Enhancing arabic bread quality and shelf life stability using bread improvers

Arabic breads is produced mainly from hard red winter wheat (HRWW) and have relatively little crumb, dense texture, form pocket and are often round with golden brown crust color. The objectives of this research were to investigate the effect of different bread improvers combinations addition in enhancing the quality parameters of Arabic bread. Therefore, the ability of Arabic bread for rolling, folding and overall quality were evaluated during the Arabic bread storage period for 2 days. It was found that there was significant effect of bread improvers combinations (Arabic gum "AG" * Mongglycerides "MG" *alpha-amylase) addition on the ability of Arabic bread for rolling and folding on the second day (P ≤ 0.1). The highest white Arabic bread quality was obtained significantly from addition of low AG, high of MG and high alpha-amylase combination and high AG, low of MG and high alpha-amylase combination. While, low of AG, high of MG and low alpha-amylase combination and high of AG, high of MG and low alpha-amylase combination significantly exhibited the highest overall quality for the Arabic bread made from whole flour.

Effect of proving time on the quality of frozen pre-baked French style rolls elaborated with the addition of wholegrain flour and enzymes

Proving is a step in the breadmaking process that can be crucial in determining the final characteristics of the product presented to the consumer. The objective of this work was to evaluate the effect of proving time on the quality of frozen pre-baked French style rolls elaborated with the addition of wholegrain flour and enzymes. With this objective, doughs from six different formulations were allowed to ferment to different stages of proving. The first stage corresponded to the stage where the dough presented the maximum point of volume development without losing its resistance to touch. The second stage was soon after the first one, being characterized by a loss of resistance to touch but without a marked loss of volume. The rolls were evaluated for their specific volume, crumb texture (firmness and springiness), oven spring, shape, cut opening and cut height. The results showed that the proving time influenced various characteristics of the pre-baked French bread. A longer proving time tended to result in greater specific volume of the rolls with greater crumb springiness, but with a less firm crumb and reduced cut opening and cut height. The oven spring and shape were not altered by the proving time. The increase in volume was the result of increases in the width and length of the rolls. This study showed that the proving time was one of the factors responsible for the collapse in the structure of the pre-baked rolls, and that an adequate formulation could overcome the loss in cut opening and cut height resulting from a longer proving time.