Significance of healthy viscous dietary fibres on the performance of gluten‐free rice‐based formulated breads

The impact of associated viscous dietary fibres (hydroxypropylmethylcellulose semi‐firm – SFE‐ and weak – NE‐gel forming, and barley ß‐glucan, BBG) incorporated at different amounts (1.6–7.5%, flour basis) into gluten‐free rice‐based dough formulations on the breadmaking performance and staling behaviour of hydrated (70–110%, flour basis) fibre‐flour composite blends has been investigated. Single BBG addition fails to mimic gluten visco‐elasticity properly, but simultaneous incorporation of either SFE or NE contributes to bread improvement in terms of bigger volume and smoother crumb. 3.3 g of BBG (70% purity) and 104 mL of water addition to 100 g rice flour provided sensorially accepted breads (7.6/10) with a theoretical ß‐glucan content of 1.24 g per 100 g GF bread that would allow a daily ß‐glucan intake of 3 g provided a bread consumption of 240 g day^?1. Complementary tests should be carried out to know the amount and molecular weight of ß‐glucan in the final bread before assuring the nutritional benefit of this addition.     

Nutritional,microbial and sensory attributes of bread fortified with defatted watermelon seed flour

The utilisation of natural food supplements to fortify staples is considered as one of the effective means of dealing with global food nutrient deficiency. Herein, we report the nutritional, microbial and sensorial characteristics of defatted watermelon seed fortified bread. The protein content and level of micronutrients such as phosphorus, potassium, iron and calcium increased with increasing proportion of watermelon seed flour in the bread. Notably, calcium resulted as the highest micronutrient in the bread samples, whereas the content of iron in the fortified samples improved significantly. The defatted watermelon seed flour had a high iron content of about 12.1 mg/100 g as compared to the normal (unfortified) bread of 0.01 mg/100 g. The total microbial count results for all the fortification levels complied with the acceptable microbial quality requirement. Lastly, the consumer acceptability test did not show any significant difference between all levels of fortification with watermelon seed flour.     

Fortification of Wheat Bread with Agroindustry By‐Products: Statistical Methods for Sensory Preference Evaluation and Correlation with Color and Crumb Structure

The use of agroindustry by‐products (BP) for fortification of wheat bread can be an alternative to waste disposal because BP are appealing sources of dietary fiber. Moreover, it may also contribute to indirect income generation. In this study, sensory, color, and crumb structure properties of breads fortified with fiber rich fraction recovered from four types of agroindustry BP were tested, namely orange (OE), pomegranate (PE), elderberry (EE), and spent yeast (YE). Statistical models for sensory preference evaluation and correlation with color and crumb structure were developed. External preference mapping indicated consumer preferences and enabled selection of the concentrations of BP fibre‐rich fraction with best acceptance, namely 7.0% EE, 2.5% OE, 5.0% PE, and 2.5% YE. Data collected from image analysis complemented sensory profile information, whereas multivariate PLS regression provided information on the relationship between “crust color” and “crumb color” and instrumental data. Regression models developed for both sensory attributes presented good fitting (R²Y > 0.700) and predictive ability (Q² > 0.500), with low RMSE. Crust and crumb a* parameters had a positive influence on “crust color” and “crumb color” models, while crust L* and b* had a negative influence.     

In vivo effect of oat cereal β‐glucan on metabolic indexes and satiety‐related hormones in diet‐induced obesity C57‐Bl mice

This study explored the dose‐dependent effect of oat cereal β‐glucan on improving metabolic indexes of obesity mice. C57‐Bl mice were randomized to chow diet (N) group and high fat diet group and other three doses of oat β‐glucan groups (low β‐glucan, medium β‐glucan, and high β‐glucan). Energy intake, glucose, lipids, and appetite related hormones were tested. Dose‐dependent relation was observed on oat β‐glucan doses and body weight change, average energy intake, total cholesterol, HDL cholesterol, plasma neural peptide Y, arcuate neural peptide Y mRNA, and arcuate neural peptide Y receptor 2 mRNA level. Oat β‐glucan helped to increase plasma peptide Y‐Y and intestine peptide Y‐Y expression in obesity mice.     

Preparation of spent brewer's yeast β-glucans for potential applications in the food industry

A preparation of β‐glucan, obtained from spent brewer's yeast, was evaluated for potential food applications. This material was autolysed and the cell walls that were obtained were homogenized, extracted firstly with alkali, then with acid, and then spray dried. Effects of the homogenization on the chemical composition, rheological properties and functional properties of β‐glucan were investigated. Homogenized cell walls exhibited higher β‐glucan content and apparent viscosity than those which had not been homogenized because of fragmentation of the cell walls. When compared with commercial β‐glucan from baker's yeast, it was found that the β‐glucan obtained from this study had higher apparent viscosity, water‐holding capacity and emulsion stabilizing capacity, but very similar oil‐binding capacity. These findings suggest that β‐glucan obtained from brewer's yeast can be used in food products as a thickening, water‐holding, or oil‐binding agent and emulsifying stabilizer.     

Pomegranate seed powder as a functional component of gluten‐free bread (Physical,sensorial and antioxidant evaluation)

The purpose of this study was to evaluate the effect of the addition of pomegranate seed powder (PSP) on physical, sensorial and antioxidant properties of gluten‐free bread. The PSP was incorporated at different levels (2.5%, 5.0%, 7.5% and 10%) into formula of gluten‐free bread. Control gluten‐free bread made without any addition of PSP was used for comparison. The results showed that the specific volume and springiness of gluten‐free breads increased, whereas hardness and chewiness decreased significantly with increasing PSP addition. The addition of PSP into gluten‐free bread decreased the lightness and yellowness of crumb and crust colour, while redness increased. Total phenolics content (TPC) increased from 46% to 181% with PSP addition (2.5%–10%). Moreover, antioxidant activity was significantly higher for bread with PSP. For bread with the highest percentage of PSP, the highest antioxidant activity was obtained. For sensorial and antioxidant activity, the optimum level of PSP addition was found to be 7.5%.     

Prebiotic effects of fermentable carbohydrate polymers may be modulated by faecal bulking of non‐fermentable polysaccharides in the large bowel of rats

This study investigated the impact of supplementary fermentable polysaccharides inulin (a prebiotic) and barley β‐glucan on the large bowel, when consumed against a background high or low intake of mixed non‐starch polysaccharide. Rats were fed for 28 days with diets containing high (15%) and low (5%) background dietary fibre (BDF; cellulose plus sugar beet fibre), with or without 5% supplementary fermentable fibre (SFF; inulin or barley β‐glucan). High‐BDF diets unsupplemented with inulin or barley β‐glucan caused greater improvement than supplemented low‐BDF diets in several parameters linked to gut health: they increased colonic Bifidobacterium spp., butyric acid concentration in the caecum, and colonic crypt depth more than inulin and barley β‐glucan. For these parameters, inulin and barley β‐glucan added little to the effects of the high‐BDF diet alone. Furthermore, by allowing for dilution due to the greater faecal bulk induced by the mixed fibre compared with inulin or barley β‐glucan, the total quantity of butyric acid in the colon of BDF‐fed rats was greatly amplified. Interpretation of the effects of prebiotics in diets containing dietary fibre requires concurrent analysis of the multiple effects of non‐fermentable bulk.     

Effect of different iron compounds on wheat and gluten‐free breads

BACKGROUND: Iron fortification of bread often results in sub‐optimal quality of the final product due to undesirable changes in the physical characteristics and sensory properties of the bread. In this study both the form of iron (soluble, insoluble or encapsulated) and the type of bread (wheat or gluten‐free) were varied in order to investigate the effect of iron and gluten on the product characteristics. RESULTS: The effect of iron on the quality characteristics of the breads investigated depended on iron type, but not on iron solubility. Colour, crust firmness, specific volume, cell number and uniformity as well as aroma were the attributes that were mainly affected in iron‐enriched wheat bread. In some cases, specific volume was 30% lower than that of the control sample, while cell uniformity was significantly lower, as low as 50% of the control sample in some fortified samples. In gluten‐free breads, differences between unfortified and fortified samples included colour, crust firmness, cell number, ‘moisture’ odour, metallic taste and stickiness. In some cases, the sensory scores were better for fortified samples. CONCLUSIONS: Differences due to iron fortification were less pronounced in gluten‐free compared to wheat breads. The choice of the appropriate iron compound which will not cause adverse quality changes is still a challenge. Copyright © 2010 Society of Chemical Industry     

Supplementation of common white bread by coriander leaf powder

Coriander leaves are widely used worldwide as a very common garnish in almost all types of Western, Oriental, and Arabic culinary. It is rich in the beneficial components of antioxidants, trace elements, and essential oils. Bread enriched with coriander leaf powder is therefore likely to have greater acceptability to consumers compared to unfortified bread. In the present study the antioxidant and sensory analyses along with baking and staling characteristics of such breads at supplementation levels of 1.0, 3.0, 5.0, and 7.0%(w/w) on wheat flour have been investigated. Results show that supplementation with coriander leaf powder bettered the crumb moisture content with only a little increase in crumb firmness. A substantial improvement in sensory characteristics was observed with the supplemented breads. A sharp increase in antioxidant content was an important beneficial fortification effect observed in the fortified breads. Coriander leaf content between 3.0 and 5.0% was found to be the optimum supplementation level that offered the best compromise for highest acceptability of the fortified breads.     

Diet high in oat β-glucan activates the gut-hypothalamic (PYY₃₋₃₆-NPY) axis and increases satiety in diet-induced obesity in mice

This study tested the effects of (1→3),(1→4) β‐D ‐glucan from oats, on activation of the gut‐hypothalamic (PYY_3–36‐NPY) axis, satiety, and weight loss in diet‐induced obesity (DIO) mice. DIO mice were fed standard lab chow diets or varied doses of β‐glucan for 6 weeks. Energy intake, satiety, body weight changes and peptide Y‐Y_3‐36 (PYY_3‐36) were measured together with a satiety test and measurement of neuropeptide Y (NPY) mRNA expression in the hypothalamic arcuate nucleus (Arc). The average energy intake (‐13%, p<0.05) and body weight gain was lower with increasing β‐glucan over 6 wk with acute suppression of energy intake over 4 h. The highest β‐glucan diet significantly increased plasma PYY_3‐36, with suppression of Arc NPY mRNA.     

大豆蛋白在面包中应用的研究

本课题对大豆蛋白在面包中的应用进行了研究,确定了将脱脂豆粉添加于面粉制作大豆蛋白强化面包的配方和工艺条件。所做强化面包体积增大,面包心无粘感,无豆腥味,其蛋白质含量比未强化前提高50％以上,并且面包重量增加、抗老化性提高,各项质量指标均符合我国面包质量标准。     

Evaluation of antioxidant, rheological and sensorial properties of wheat flour dough and bread containing ginger powder

The effects of addition of ginger powder (0, 3, 4.5 and 6%) in formulation were examined in order to obtain an antioxidant-enriched bread with good physico chemical and sensorial properties. The rheological properties of doughs were evaluated using dynamic rheological measurements. Physical properties, total phenolics content (TPC- Folin-Ciocalteau method), radical scavenging activity (RSA- DPPH assay) and sensory analysis (hedonic test) of the supplemented bread were determined.The highest TPC (0.48 and 0.71 mg GAE/g DW on crumb and crust respectively) and RSA activity (0.15 and 0.24 μmol DPPH/mg DW ml⁻¹ on crumb and crust respectively) were achieved in the bread having the highest percentage of ginger powder (6%). But this sample showed the worst results regarding the rheological properties indicating that the dough and the bread had a tough structure. Moreover, by sensory evaluation this bread sample was not acceptable.Among the studied samples, bread with 3% of ginger powder showed good rheological characteristics and doubled anti-oxidant content compared to the control bread and the highest sensorial acceptability.     

Biofortification of folates in white wheat bread by selection of yeast strain and process

We here demonstrate that folate content in yeast fermented food can be dramatically increased by using a proper (i) yeast strain and (ii) cultivation procedure for the selected strain prior to food fermentation. Folate levels were 3 to 5-fold higher in white wheat bread leavened with a Saccharomyces cerevisiae strain CBS7764, cultured in defined medium and harvested in the respiro-fermentative phase of growth prior to dough preparation (135-139 microg/100 dry matter), compared to white wheat bread leavened with commercial Baker's yeast (27-43 microg/100 g). The commercial Baker's yeast strain had been industrially produced, using a fed-batch process, thereafter compressed and stored in the refrigerator until bakings were initiated. This strategy is an attractive alternative to fortification of bread with synthetically produced folic acid. By using a high folate producing strain cultured a suitable way folate levels obtained were in accordance with folic acid content in fortified cereal products.     

Staling of cereal bran enriched cakes and the effect of an endoxylanase enzyme on the physicochemical and sensorial characteristics

Abstract: The staling of cakes enriched with untreated brans and endoxylanase‐treated brans was evaluated by monitoring the changes in physicochemical, thermal, and sensorial properties of cakes during 7‐d storage. Oat and rice bran were treated with different levels (0, 70, and 700 ppm) of an endoxylanase enzyme and added to cakes on 30% flour weight basis. Moisture losses, water activity, crumb firmness, starch retrogradation, and sensorial characteristics were used as staling indicators. Avrami‐type equations were efficiently used for modeling the starch retrogradation kinetics, while linear models most adequately described crumb firming kinetics. Cake staling induced an increase in crumb firmness and enthalpy of amylopectin retrogradation, and a decrease in crumb moisture and sensory quality and acceptability scores of cakes. Oat bran‐containing cakes better maintained their characteristics compared to the ones containing rice bran along the 7‐d storage. Endoxylanase treatment of brans delayed the changes naturally induced during staling in crumb moisture content, amylopectin retrogradation enthalpy, and crumb firmness in the respective cakes. Deterioration of the sensorial characteristics was slower for the cakes containing endoxylanase‐treated brans, as well. The level of endoxylanase treatment did not differentiate significantly (P < 0.05) any of the staling indicators. Overall, this study demonstrated that addition of endoxylanase‐treated brans can result in cakes with improved nutritional characteristics and increased shelf life. Practical Application: The results of the study show the potential of using enzymes to modify underutilized food sources that can be properly incorporated in baked goods, improving their nutritional value, their quality characteristics, and providing longer shelf life. The developed procedure and results can be utilized by the bakery industry to make high fiber and low cost bakery products with improved sensorial characteristics that are appealing to the consumers.     

Effect of the shape of rice starch granules on flour characteristics and gluten‐free bread quality

The effect of three different rice varieties with different starch shapes (Seolgaeng (SG), round starch structure; Samkwang (SK), polygonal starch structure and Boramchan (BRC), polygonal starch structure) on rice flour characteristics and gluten‐free bread baking quality was investigated. Rice flours were produced by dry milling and passed through a 200 mesh sieve. Electron microscopy revealed that the structure of SG grains, with round starch granules, possessed larger void spaces than SK and BRC, composed of polygonal starch granules. For this reason, SG grain had low grain hardness and consequently, it was milled to a fine flour with low damaged starch content. The thermo‐mechanical properties were determined by Mixolab, which revealed that SG was gelatinised rapidly and maintained high viscosity after gelatinisation. These characteristics gave SG flour the ability to build up bread structure without gluten. Specific volume and crumb hardness of gluten‐free rice breads made of SG, SK and BRC flours were 3.37, 3.11 and 2.12 mL g^?1 and 2.61, 2.76 and 6.46 N, respectively. The SG flour with round starch structure is appropriate for making gluten‐free rice breads.     

Application of Bifidobacteria as Starter Culture in Whole Wheat Sourdough Breadmaking

This investigation is aimed at developing a new cereal-based product, with increased nutritional quality, by using Bifidobacterium pseudocatenulatum ATCC 27919 as starter in whole wheat sourdough fermentation and evaluating its performance. Four different sourdough levels (5%, 10%, 15%, and 20% on flour basis) in bread dough formulation were analysed. The effects of the use of bifidobacteria in sourdough bread were comparatively evaluated with controls (yeast and/or chemically acidified sourdough with antibiotics). The sourdough and dough fermentative parameters analysed were pH, total titratable acidity, d/l-lactic and acetic acids. Bread performance was evaluated by specific volume, slice shape, crumb structure and firmness, crust and crumb colour, pH, total titratable acidity, and d/l-lactic and acetic acids, phytate, and lower myo-inositol phosphate contents. The sourdough breads showed similar technological quality to the control sample, with the exception of specific bread volume (decreased from 2.46 to 2.22 mL/g) and crumb firmness (increased from 2.61 to 3.18 N). Sourdough inoculated with bifidobacteria significantly increased the levels of organic acids in fermented dough and bread. The Bifidobacterium strain contributed to the fermentation process, increasing phytate hydrolysis during fermentation owing to the activation of endogenous cereal phytase and its own phytase, resulting in bread with significantly lower phytate levels (from 7.62 to 1.45 μmol/g of bread in dry matter). The inclusion of sourdough inoculated with bifidobacteria made possible the formulation of whole wheat bread with positive changes in starch thermal properties and a delay and decrease in amylopectin retrogradation.     

Bioavailability of zinc in fiber‐enriched bread fortified with zinc sulphate

The present study aimed to reduce the caloric value of bread by substituting a part of wheat flour with artichoke bracts at levels of 5%, 10% and 15% without sacrificing taste, texture or acceptability. Moreover, considerable trials had been made to reduce zinc deficiency in wheat bread and fiber‐enriched bread and also to study the effect of fiber on zinc bioavailability. Therefore, zinc sulphate was added to bread at levels of 40, 60, 80, 100 and 120 mg/100 g edible portion. The results from this study show that: (i) The addition of artichoke bracts to wheat flour increased the water absorption, arrival time, development time, and weakening of the dough as the level of artichoke bracts increased, while dough stability decreased. (ii) Mixing wheat flour with increasing amount of artichoke bracts increased the content of protein, fiber and total essential amino acids, also all essential amino acids increased in wheat bread and fiber‐enriched bread after fortification with zinc sulphate at a level of 100 mg/100 g edible portion except methionine, threonine and tyrosine. (iii) The best level of zinc sulphate to give the best bioavailability for zinc is 100 mg/100 g edible portion. (iv) Evaluation of fortified wheat bread and fiber‐enriched bread with zinc sulphate showed no significant difference by test panel.     

Effect of cholesterol‐reduced and zinc fortification treatments on physicochemical,functional, textural,microstructural and sensory properties of soft cheese

The aim of this study was to produce and evaluate a soft cheese fortified with zinc and with cholesterol‐reduced content. To meet this objective, a cream base was prepared, from which cholesterol was removed using β‐cyclodextrin as extracting agent. Then, cholesterol‐reduced content cheese with and without the addition of zinc salts (ZnSO₄ or ZnCl₂) was produced. Additionally, a cheese without any treatment was prepared. Furthermore, physicochemical, textural, functional, microstructural and sensory determinations were performed. As a result, 87–94% zinc‐fortified and 93% cholesterol‐reduced cheese samples were obtained, which had similar sensorial characteristics to the cheese without treatment.     

β‐1,3/1,6‐Glucans and Immunity: State of the Art and Future Directions

The innate immune system responds in a rapid and non‐specific manner against immunologic threats; inflammation is part of this response. This is followed by a slower but targeted and specific response termed the adaptive or acquired immune response. There is emerging evidence that dietary components, including yeast‐derived β‐glucans, can aid host defense against pathogens by modulating inflammatory and antimicrobial activity of neutrophils and macrophages. Innate immune training refers to a newly recognized phenomenon wherein compounds may “train” innate immune cells, such that monocyte and macrophage precursor biology is altered to mount a more effective immunological response. Although various human studies have been carried out, much uncertainty still exists and further studies are required to fully elucidate the relationship between β‐glucan supplementation and human immune function. This review offers an up‐to‐date report on yeast‐derived β‐glucans as immunomodulators, including a brief overview of the current paradigm regarding the interaction of β‐glucans with the immune system. The recent pre‐clinical work that has partly decrypted mode of action and the newest evidence from human trials are also reviewed. According to pre‐clinical studies, β‐1,3/1,6‐glucan derived from baker's yeast may offer increased immuno‐surveillance, although the human evidence is weaker than that gained from pre‐clinical studies.     

Effects of two barley β-glucan isolates on wheat flour dough and bread properties

The effects of wheat flour fortification with two different molecular weight barley β-glucan isolates (1.00 × 10⁵, BG-100 and 2.03 × 10⁵, BG-200) on the rheological properties of dough and bread characteristics, using flours from two wheat cultivars that differ in their breadmaking quality, have been examined. The farinograph water absorption of doughs and the moisture content and water activity of the breads increased with increasing β-glucan content; the β-glucan isolate with the higher molecular weight (BG-200) exerted a greater effect than did BG-100. The addition of β-glucans to the dough formula increased the development time, the stability, the resistance to deformation and the extensibility of the poor breadmaking quality doughs, as well as the specific volumes of the respective breads, exceeding even that of the good breadmaking cultivar. Furthermore, the colour of the bread crumbs got darker and their structure became coarser, whereas the bread crumb firmness decreased with increasing level of β-glucan addition. Generally, the BG-200 was more effective in increasing the specific bread volume and reducing the crumb firmness, especially when used to fortify the poor breadmaking quality flour. The results further indicate a requirement for optimisation of the fortified doughs (level and molecular size of the β-glucan) to maximise bread quality attributes (loaf volume, texture, and staling events).