Effect of wheat flour protein variations on sensory attributes, texture and staling of Taftoon bread

The quality of flat breads depends in part on the textural properties of breads during storage. These properties are largely affected by flour protein quality and quantity. The present study aimed to examine differences between sensory properties, textural and staling of Tandoori breads made from flours of different quality and different quantities of protein. This was implemented by using three flours with 9.4, 11.5 and 13.5% protein contents and different protein qualities shown by Zeleney sedimentation volume 16.25, 22.75 and 23.25 mL respectively. Bread strips were submitted to uniaxial compression between two parallel plates on an Instron Universal Testing machine, and firmness of the breads was determined. Results indicated the differences in the sensory attributes of breads produced by flours of different protein content and quality, demonstrating that high protein high quality flours are not able to sheet and expand under the high temperature - short time conditions employed in Taftoon bread production and are therefore not suitable for this kind of bread. Results showed that flour with 11.5% protein content, produced bread with better sensory characteristics and acceptable storage time.

Influence of xylanase addition on the characteristics of loaf bread prepared with white flour or whole grain wheat flour

The aim of this study was to verify the influence of the addition of the enzyme xylanase (four concentrations: 0, 4, 8, and 12 g.100 kg-1 flour) on the characteristics of loaf bread made with white wheat flour or whole grain wheat flour. Breads made from white flour and added with xylanase had higher specific volumes than those of the control sample (no enzyme); however, the specific volume did not differ significantly (p < 0.05) among the breads with different enzyme concentrations. All formulations made from whole grain wheat flour and added with xylanase also had specific volumes significantly higher than those of the control sample, and the highest value was found for the 8 g xylanase.100 kg-1 flour formulation. With respect to moisture content, the formulations with different enzyme concentrations showed small significant differences when compared to the control samples. In general, breads made with the addition of 8 g enzyme.100 kg-1 flour had the lowest firmness values, thus presenting the best technological characteristics.

A comparative study among methods used for wheat flour analysis and for measurements of gluten properties using the Wheat Gluten Quality Analyser (WGQA)

This study aimed at comparing both the results of wheat flour quality assessed by the new equipment Wheat Gluten Quality Analyser (WGQA) and those obtained by the extensigraph and farinograph. Fifty-nine wheat samples were evaluated for protein and gluten contents; the rheological properties of gluten and wheat flour were assessed using the WGQA and the extensigraph/farinograph methods, respectively, in addition to the baking test. Principal component analysis (PCA) and linear regression were used to evaluate the results. The parameters of energy and maximum resistance to extension determined by the extensigraph and WGQA showed an acceptable level for the linear correlation within the range from 0.6071 to 0.6511. The PCA results obtained using WGQA and the other rheological apparatus showed values similar to those expected for wheat flours in the baking test. Although all equipment used was effective in assessing the behavior of strong and weak flours, the results of medium strength wheat flour varied. WGQA has shown to use less amount of sample and to be faster and easier to use in relation to the other instruments used.

The production of Pleurotus sajor-caju in peach palm leaves (Bactris gasipaes) and evaluation of its use to enrich wheat flour

The aim of this study was to evaluate of Pleurotus sajor-caju production in peach palm leaves and the addition of different fractions of mushroom powder to wheat flour to increase its nutritional value without changing its characteristics. The best yield (48.4%), biologic efficiency (4.5%), and Pr (0.36 g/day) values were obtained using 20% inoculum fraction and 10% rice bran fraction. The Pleurotus sajor-caju fruiting body cultivated under these conditions had the following composition in 100 g: 29.91 g (carbohydrates), 42.92 g (proteins), 1.24 g (lipids), 15.93 g (fibers), 7.42 g (ashes), 1.6 g (phosphorus), 2.7 g (potassium), 8.73 mg (iron), 23.75 mg (sodium), 0.34 mg (thiamine), and 0.57 mg (riboflavin). The wheat flour with mushroom powder had reduced sugar content, but it did not have increased fat content. The fiber, protein, phosphorus, potassium, iron, and riboflavin contents were increased mainly when 10% mushroom powder was added to the wheat flour. Furthermore, this flour does not undergo drastic alterations in its physicochemical characteristics such as in moisture, wet gluten, color, and falling number.

Influence of the wheat flour extraction degree in the quality of bread made with high proportions of β-glucan

β-glucan is currently one of the most important bioactive substances. Hence, there is a growing interest in the production of various foods containing β-glucan. The study examines the influence of the degree of wheat flour extraction in the quality of breads with high β-glucan content. Rheological tests were conducted on dough. Volume, mass, color and texture of bread were measured after baking. We observed that increasing the degree of extraction caused an increase in the storage and loss modulus. All of the bread made from the different flours were smaller in volume after the addition of β-glucan, although the yield increased. The crumb color of β-glucan-added breads was darker than the control samples. Control samples were higher in textural parameters (firmness, gumminess and chewiness). β-glucan-added samples had decreased porosity. The results revealed that using very strong flour with a high protein content results in a high quality β-glucan bread with a higher nutritional value due to the high total dietary fiber and β-glucan content.

Effects of whole-wheat flour and bordeaux grape pomace (Vitis labrusca L.) on the sensory, physicochemical and functional properties of cookies

Abstract Grape pomace, which is derived from the skin and seeds, is the residue from the production of grape juice and wine. It corresponds to up to 20% of the total volume and it contains a high level of dietary fibers and bioactive compounds. In the Brazilian market, there is no product containing grape pomace as a replacement for conventional wheat flour. Thus, this study aimed to assess the effects of whole-wheat flour and organic Bordeaux grape pomace (Vitis labrusca L.) on the sensory, physicochemical and functional properties of cookies using response surface methodology (RSM). The regression models indicated that the addition of whole-wheat and organic grape pomace decreased (p < 0.0001) the water activity and significantly increased the content of fibers, hardness, brittleness, antioxidant activity and total phenolic content of the cookies. The RSM models presented suitable R2 and R2adj values (> 65% of explained data variability), except for brittleness. The sensory evaluation results revealed that no significant differences (p > 0.05) were observed for the cookie samples, implying that the addition of grape pomace and whole-wheat flour did not negatively affect the preference of cookies.

Effect of different proportions of brea gum in the functional characteristics of wheat flour starch: impact on the physical quality of bread

The aim of this work was to study the changes induced by BG in the behaviour of wheat starch, and observe the influence of these variations on the quality of a basic white bread. The effect of four BG addition levels in the wheat flour functional characteristics (WAI, WSI, and pasting properties) and bread quality (physical parameters, crumb grain structure, moisture and hardness) was investigated. The highest levels of BG (1% and 2%) decreased the peak viscosity, and increased the stability and setback of the flour. This was due to a lower gelatinization of the starch granules, caused by a competition for water between the hydrocolloid and starch. These changes influenced the bread quality. The loaves added with 1% and 2% of BG presented smaller alveoli: this resulted in more compact, hard and less airy crumbs. Nevertheless, the moisture of the samples at 1% and 2% of added gum was higher than the control bread. However, the incorporation of BG at 0.5% did not affect the pasting parameters and bread quality, but increased moisture of crumb, so this concentration would be most recommended for baking, since higher humidity could favour the shelf- life of the product.

Thermogravimetric analysis of water release from wheat flour and wheat bran suspensions

Bran is hygroscopic and competes actively for water with other key components in baked cereal products like starch and gluten. Thermogravimetric analysis (TGA) of flour–water mixtures enriched with bran at different incorporation levels was performed to characterise the release of compartmentalised water. TGA investigations showed that the presence of bran increased compartmentalised water, with the measurement of an increase of total water loss from 58.30 ± 1.93% for flour only systems to 71.80 ± 0.37% in formulations comprising 25% w/w bran. Deconvolution of TGA profiles showed an alteration of the distribution of free and bound water, and its interaction with starch and gluten, within the formulations. TGA profiles showed that water release from bran-enriched flour is a prolonged event with respect to the release from non-enriched flour, which suggests the possibility that bran may interrupt the normal characteristic processes of texture formation that occur in non-enriched products.

Component-resolved diagnosis of wheat flour allergy in baker's asthma.

Baker's asthma is one of the most common types of occupational asthma and its prevalence is increasing in the last years. Diagnosis of occupational asthma is complex. The poor specificity of current diagnostic approaches may be associated with insufficient purity of wheat extracts or lack of inclusion of major allergens in them. In this work, we use microarray technology to characterize the allergenic profiles of baker's asthma patients from three regions in Spain and to analyze the influence of other environmental allergens on the sensitization pattern.

Application of Improved Direct Calibration for Hyperspectral image processing: Detecting peanut traces in wheat flour.

NIR Hyperspectral imaging (1000-2500 nm) combined with IDC allowed the detection of peanut traces down to adulteration percentages 0.01% Contrary to PLSR, IDC does not require a calibration set, but uses both expert and experimental information and suitable for quantification of an interest compound in complex matrices. The obtained results shows the feasibility of using HSI systems for the detection of peanut traces in conjunction with chemical procedures, such as RT-PCR and ELISA

Detection of peanut traces in wheat flour through NIR hyperspectral imaging spectroscopy

- NIR Hyperspectral images (1000-2200 nm) allowed the detection of peanut traces down to adulteration percentages 0.01 % - Determination coefficient of R2= 0.946 was found for the quantification of peanut adulteration from 10% to 0.1%. - The obtained results shows the feasibility of using HSI systems for the detection of peanut traces in conjuction with chemical procedures, such as RT-PCR and ELISA to facilitate quality control surveyance on food product processing lines.

Hyperspectral to multispectral imaging for detection of tree nuts and peanut traces in wheat flour

In current industrial environments there is an increasing need for practical and inexpensive quality control systems to detect the foreign food materials in powder food processing lines. This demand is especially important for the detection of product adulteration with traces of highly allergenic products, such as peanuts and tree nuts. Manufacturing industries dealing with the processing of multiple powder food products present a substantial risk for the contamination of powder foods with traces of tree nuts and other adulterants, which might result in unintentional ingestion of nuts by the sensitised population. Hence, the need for an in-line system to detect nut traces at the early stages of food manufacturing is of crucial importance. In this present work, a feasibility study of a spectral index for revealing adulteration of tree nut and peanut traces in wheat flour samples with hyperspectral images is reported. The main nuts responsible for allergenic reactions considered in this work were peanut, hazelnut and walnut. Enhanced contrast between nuts and wheat flour was obtained after the application of the index. Furthermore, the segmentation of these images by selecting different thresholds for different nut and flour mixtures allowed the identification of nut traces in the samples. Pixels identified as nuts were counted and compared with the actual percentage of peanut adulteration. As a result, the multispectral system was able to detect and provide good visualisation of tree nut and peanut trace levels down to 0.01% by weight. In this context, multispectral imaging could operate in conjuction with chemical procedures, such as Real Time Polymerase Chain Reaction and Enzyme-Linked Immunosorbent Assay to save time, money and skilled labour on product quality control. This approach could enable not only a few selected samples to be assessed but also to extensively incorporate quality control surveyance on product processing lines.

Detection and quantification of peanut traces in wheat flour by near infrared hyperspectral imaging spectroscopy using principal-component analysis

The use of a common environment for processing different powder foods in the industry has increased the risk of finding peanut traces in powder foods. The analytical methods commonly used for detection of peanut such as enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR) represent high specificity and sensitivity but are destructive and time-consuming, and require highly skilled experimenters. The feasibility of NIR hyperspectral imaging (HSI) is studied for the detection of peanut traces down to 0.01% by weight. A principal-component analysis (PCA) was carried out on a dataset of peanut and flour spectra. The obtained loadings were applied to the HSI images of adulterated wheat flour samples with peanut traces. As a result, HSI images were reduced to score images with enhanced contrast between peanut and flour particles. Finally, a threshold was fixed in score images to obtain a binary classification image, and the percentage of peanut adulteration was compared with the percentage of pixels identified as peanut particles. This study allowed the detection of traces of peanut down to 0.01% and quantification of peanut adulteration from 10% to 0.1% with a coefficient of determination (r2) of 0.946. These results show the feasibility of using HSI systems for the detection of peanut traces in conjunction with chemical procedures, such as RT-PCR and ELISA to facilitate enhanced quality-control surveillance on food-product processing lines.