Food Technology
Mohammad Fazli Rad; Jafar Milani; Sepide Haghighat
Abstract
IntroductionWheat plays a major role in global nutrition but it cannot be used without processing. The nutritional importance of wheat flour is due to the presence of gluten proteins that create viscoelastic properties. Gluten as a protein inhibits the staleness of bread. Physical modification of flour ...
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IntroductionWheat plays a major role in global nutrition but it cannot be used without processing. The nutritional importance of wheat flour is due to the presence of gluten proteins that create viscoelastic properties. Gluten as a protein inhibits the staleness of bread. Physical modification of flour is a safe method without using any kind of chemicals. Physical modification of flour includes heat treatment and particle size classification. Particle size distribution is the most widely used technique for classifying solid particles, which is effective in improving rheological properties by affecting the physicochemical properties of flour during hydration, such as water absorption, solvent retention, sedimentation, and adhesion properties. Heat treatments, depending on the intensity of temperature and process time, by modifying starch granules, denaturing proteins, and deactivating enzymes, reducing microbial load, and even modifying flavor and aroma are suggested as a suitable way to improve the quality of bread, especially for weak flour. Considering that the interaction of particle size with wet and dry heating of wheat flour on the rheological properties of dough and staleness of bread has not been studied so far. In this research, by dividing wheat flour with different particle sizes and using wet and dry heat treatments for modification the functional characteristics of wheat flour and the improvement of the rheological characteristics of dough and staleness of bread were investigated.Materials and MethodsThe content of moisture, pH, ash, protein, and Zeleny number of wheat flour was measured using the AACC standard method (2000), and wet and dry gluten with the standard number (9639-1, 3) was measured. To classify the size of the particles, wheat flour was divided by a shaker sieve with different sizes of 180, 150, and 125 microns, then under the influence of dry heat treatment for 10 minutes at 100 degrees Celsius and moist heat treatment with 16% humidity for 5 minutes at a temperature of 96 degrees Celsius was placed. Materials for bread formulation for 100 g of wheat flour included 58 ml of water, 2.5 g of sugar, 1 g of salt, 1 g of vegetable oil, and 2 g of yeast. The rheological parameters of the dough were measured by an alveography device. To check the staleness of bread during the storage period, moisture tests of core and shell, blue activity of core to shell, analysis of bread texture, and DSC were performed. Finally, the factorial test was used to investigate the effects of particle size and heat treatment on wheat flour, and Duncan's multiple range test was used to compare the means at the 5% probability level. Results and DiscussionThe results showed that the effect of particle size and dry heat treatment on dough rheology and water activity of bread core and crust was significant, while moist heat treatment had significantly more bread core moisture (p<0.05). According to the results, dry heat treatment did not affect the texture of bread (p>0.05), while the use of flour obtained from moist heat treatment with a particle size of 180 microns led to the improvement of bread texture by reducing the hardness and chewability (p<0.05). The results of thermal analysis showed that the moist heat treatment sample with a particle size of 180 microns had the lowest enthalpy and was the best sample (p<0.05).ConclusionIn general, the use of flour with a particle size of 180 microns and moist heat treatment to improve the rheological and staling properties of bread were the best examples.
Food Chemistry
Amir Kazemi; Asghar Mahmoudi; Mostafa Khojastehnazhand; Seyyed Hassan Fattahi
Abstract
Wheat flour is one of the most important and strategic food resources especially in developing countries. The addition of Sodium hydrosulfite to flour for improving some appearance features can have dangerous impacts on the consumer health. Therefore, detection of this harmful substance is great practical ...
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Wheat flour is one of the most important and strategic food resources especially in developing countries. The addition of Sodium hydrosulfite to flour for improving some appearance features can have dangerous impacts on the consumer health. Therefore, detection of this harmful substance is great practical significance. In the present study, the potential of Fourier transform-mid infrared (FT-MIR) spectroscopy in 400-4000 cm-1 for the fast detection of Sodium hydrosulfite powder in wheat flour was investigated. After getting the spectral data from samples, firstly some preprocessing methods were used to correct harmful and unwanted effects on spectral data, and then Principal Component Analysis (PCA) as unsupervised and Support Vector Machine (SVM) and Artificial Neural Network (ANN) models as supervised classification models and Partial Least Square Regression (PLSR) as regression model were applied to detect and quantify the adulteration in pure flour samples. The best outcomes were the accuracy of 86.66 and 86.70 for SVM and ANN models with S-G + D2 + SNV preprocessing, respectively and R2p = 0.99 For PLSR model.
Arman Naderi; Soheila Zarringhalami
Abstract
[1]Introduction: Bread is an important staple food widely consumed all over the world including Iran. The consumption of traditional breads in Iran, including Barbari, Sangak, Taftoon and Lavash, is steadily increasing because of its convenience and being a ready-to-eat food product normally consumed ...
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[1]Introduction: Bread is an important staple food widely consumed all over the world including Iran. The consumption of traditional breads in Iran, including Barbari, Sangak, Taftoon and Lavash, is steadily increasing because of its convenience and being a ready-to-eat food product normally consumed at breakfast, lunch and dinner. Hence, fortification of several types of bread with other cereals, pseudo cereals, legumes and oil seeds flours, has received considerable attention. Sesame, although referred to as “seed of immortality” and “queen of oilseeds” is considered as a rich food as it has a high nutritive quality. Apart from being a prominent oilseed (45-50%), sesame seeds are a rich source of protein (18–40%). Also, sesame was reported as a rich source of vitamins and minerals. Therefore, in the current study, the effect of wheat flour fortification with sesame flour at the ratio of 0, 5, 10 and 15 % on flour, dough, Sangak and Barbari samples properties was evaluated. Material and Methods: Proximate analysis of flour samples (sesame, wheat and composite flour samples) including acid value, moisture, ash, protein and wet gluten contents of the flour samples were determined according to the AACC methods. Water absorption, dough development time, dough stability time, degree of softening and the ratio between resistance to extension and extensibility (R/E), of prepared dough samples were determined according to AACC 21-54 and AACC 10-54 standard methods. After 2 h of bread baking the crust color parameters (L*, a* and b*) were determined using the Hunter–Lab Color flex Colorimeter (Hunter Associated Lab, Inc., Reston, VA, USA). Crumb Hardness was also measured 2 h after baking using a texture analyzer (Texture Analyzer, Brookfield, CT3, USA). The organoleptic characteristics (taste, aroma, color, texture and overall acceptability) of the prepared bread samples were evaluated by 15 trained panelists familiar with the traditional bread usually consumed, using 5-point hedonic scale (5 = like extremely, 1 =dislike extremely) test. The data was analyzed by one way analysis of variance (ANOVA). A multiple comparison procedure was performed by Duncan’s new multiple range test using SPSS Software. Significance of the difference was defined as p <0.05. Results and Discussion: According to the results obtained from flour samples analysis, sesame flour contained higher amounts of protein, lipid and ash and low amount of moisture and gluten than wheat flour. Furthermore, with increasing the amount of sesame flour, ash and protein contents of flour samples were increased, but their moisture and gluten contents were decreased. Furthermore, Farinograph parameters including water absorption and stability were decreased, but dough development time and degree of softening were increased with increasing the amount of sesame flour in the formulation. The results of Extensograph test also, showed the R/E ratio, which indicates dough stability during fermentation, was decreased when the sesame flour content increased. Therefore, the addition of sesame flour induced to weaken the gluten network formation in dough samples. The qualitative characteristics results of bread samples showed that addition of sesame flour to bread formulation tends to decrease crumb hardness and had no effect on color attributes (L*, a* and b*). Sensory evaluation results showed the higher total acceptability of Sangak and Barbari bread samples containing 10 and 5 % of sesame flour, respectively. In these ratios the color and texture of bread samples were also similar to related control bread samples. According to the results obtained in the current study and based on the functional properties of sesame flour (rich source of oil, protein, minerals, vitamins and antioxidant compounds) that reported by several previous studies, addition of 5 and 10 % of sesame flour in large scale production of Barbari and Sangak breads is recommended. Due to the high consumption of Sangak and Barbari breads in Iran, fortification of these breads can be effective in providing the daily needs of several nutrients.
Seyed Amir Tavakoli Lahijani; Fakhri Shahidi; Mahmoud Habibian; Arash Koocheki
Abstract
[1]Introduction: Bread has a major role in the diet of people in Iran. One of the important factors affecting the quality of bread is the quality of wheat flour protein called gluten. Gluten is the principal structure forming elements of most baked products, contributing to the elasticity, cohesiveness ...
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[1]Introduction: Bread has a major role in the diet of people in Iran. One of the important factors affecting the quality of bread is the quality of wheat flour protein called gluten. Gluten is the principal structure forming elements of most baked products, contributing to the elasticity, cohesiveness and viscosity characteristics of the dough. Thus, gluten substantially control the quality of wheat flour based products. Due to the importance of the role of gluten and the requirement for improving the flour quality, providing a simple, economical, and efficient method to improve the technical quality of wheat and bread is also an important and controversial challenge. Oxidizing agents are generally added to the wheat flour to accelerate the natural maturing and the flour becomes paler and yields dough with improved baking properties. However, increasing concern about their adverse effects has highlighted the need for the development of alternative oxidants. Atmospheric cold plasma (ACP) is an emerging advanced oxidation process which has recently drawn considerable interest from food scientists. Therefore, the objective of this study was to investigate the effect of non-thermal plasma treatments on the properties of wheat flour. Materials and Methods: For this purpose, medium wheat flour was prepared from local silages and treated with ACP at 25V for 0, 2, 4, 6, 8 and 10 min. Chemical composition of flour samples (moisture content, protein and ash) were determined using standard methods (AACC, 2002). Color properties, damaged starch water soluble index, wet gluten, gluten index, zeleny and falling number values, water and oil absorption capacities, swelling power and solubility of wheat flour samples were also measured. Results and Discussion: The results obtained from the measurement of properties for the treated and untreated flour showed that the water and oil absorptions, swelling power, and solubility, wet gluten, gluten index, Zeleny number and whiteness increased significantly with increasing time, while the pH, moisture content, b * and a * indices, were decreased by plasma treatment. In addition, the results showed that ACP conditions have a significant effect on functional properties that can be created floursand products with various characteristics. The results showed that plasma treatment affected the gluten index and wet gluten and techno functional properties of wheat flour. Overall, this study demonstrated that non-thermal plasma is a quick, efficient way to improve the technological properties of wheat flour, as an alternative to chemical oxidants
