In the research,36 spring wheat cultivars from Xinjiang were used to investigate flour yield,ash content,color,granularity,flour quality,paste quality and gelatinization property and to evaluate processing quality and...In the research,36 spring wheat cultivars from Xinjiang were used to investigate flour yield,ash content,color,granularity,flour quality,paste quality and gelatinization property and to evaluate processing quality and characters of stretched noodle,in order to explore relationship of milling flour quality with quality property of Xinjiang spring wheat and with processing quality of Xinjiang hand-stretched noodle,which provides theoretical references for improvement of Xinjiang spring wheat cultivars,breeding of specific cultivars(for Xinjiang stretched noodles),and advancement of stretched noodles.The results indicated that flour color is dominant among flour quality properties of Xinjiang spring wheat,which is of significant correlation with processing quality of stretched noodles.Therefore,in quality improvement of Xinjiang stretched noodles,flour yield of Xinjiang wheat should be enhanced and ash content and damaged starch should be reduced in order to improve quality of flour and stretched noodles from Xinjiang spring wheat.The indices of milling flours for Xinjiang stretched noodles are as follows:flour yield ≥60.77%,ash content ≤ 0.45%,damaged starch≤3.77%,granularity ≤108.14%,brightness(L^*)≥ 90.86,redness(a^*)≥-0.82,and yellowness(b^*) ≤9.00.展开更多
Resistant starch (RS) is the undigested starch that passes through the small intestine to the large intestine. As a functional low calorie additive, it has special applications in the food industry. Rapid visco anal...Resistant starch (RS) is the undigested starch that passes through the small intestine to the large intestine. As a functional low calorie additive, it has special applications in the food industry. Rapid visco analysis (RVA) and the Brabender farinograph were used to study the pasting properties and the viscoelasticity of blends of RS (RS3 and RS2) and three wheat flours. The wheat flours represented strong gluten wheat (SGW), intermediate gluten wheat (IGW), and weak gluten wheat (WGW) flours, at different levels of RS substitution (0, 5, 10, 15, and 20%). The influence of RS3 on the control wheat flours and RS-wheat flour blends were consistent with those of RS2. The peak, trough, and final viscosities of RS3-wheat flour blends were higher than those of the corresponding RS2-wheat flour blends. The peak, trough, breakdown, final, and setback viscosities ofwheat-RS blends decreased with an increase in resistant starch contents from 0 to 20% in the blends. The 0-20% RS-wheat flour blends were all able to form doughs. The dough development times, dough stabilities, dough breakdown times, and farinograph quality numbers for the RS-wheat flour blends decreased as the RS proportion in the blends increased. The values for RS-SGW flour blends were the highest, followed by RS-IGW and then RS-WGW flour blends. The water absorption values for RS-wheat flour blends and the mixing tolerance index for RS-WGW flour blends were found to increase significantly with an increasing proportion of RS from 0 to 20%, but the mixing tolerance index for RS-SGW and RS-IGW flour blends showed no significant differences amongst the different ratios. Correlation analysis showed that the Farinograph quality number was highly positively correlated with dough breakdown time, dough stability, and dough development time (r= 1.000, 0.958, 0.894), and highly negatively correlated with the mixing tolerance index (r =-0.890). Data from this study can be used for the development of dough-based products. It also provides a basis for RS-wheat flour blends and quality evaluation in the food industry.展开更多
The phytic acid contents of eight fractions of wheat flours from different mill streams and those in wheat brans, which were separated by different sieves into various sizes, were determined and analyzed. A rapid meth...The phytic acid contents of eight fractions of wheat flours from different mill streams and those in wheat brans, which were separated by different sieves into various sizes, were determined and analyzed. A rapid method for phytic acid assay by adding thioglycolic acid (mercapto acetic acid) with 2,2-bipyridine was used, with an acidic iron-Ⅲ-solution of known iron content. The amount ofphytate was indicated by the decrease in iron in the supernatant. Significant differences were observed in phytic acid content among different milling streams and different cultivars (P〈0.05). On an average, coarse bran had the highest phytic acid content (53.85 mg g^-1), and the shorts had 28.48 mg g^-1. The B5 break flour had a higher phytic acid content (4.8 mg g^-1) than the B7 (2.75 mg g^-1) and B8 (2.03 mg g^-1) reduction flours. Lower values were found in the B3, B6 and B7 flours (1.07, 0.79, and 0.76 mg g^-1, respectively). The phytic acid contents of bran decreased with smaller bran sizes, ranging from 54 to 5.09 mg g^-1.展开更多
The purpose of this study is to identify major factors affecting the manufacture and quality of steamed bread,consumed in Southeast Asia including China,Japan,and Korea.Hence,flours of 11 Korean wheat cultivars were u...The purpose of this study is to identify major factors affecting the manufacture and quality of steamed bread,consumed in Southeast Asia including China,Japan,and Korea.Hence,flours of 11 Korean wheat cultivars were used to evaluate quality attributes of two different styles of steamed bread,Korean style steamed bread(KSSB)and northern-style Chinese steamed bread(NSCSB).KSSB prepared more ingredients and higher optimum water absorption of dough than NSCSB because Korean consumers prefer white and glossy surface and soft crumb.KSSB showed lower height,larger diameter and volume of steamed bread,higher stress relaxation,and softer texture of crumb than NSCSB.The correlation between flour characteristics and quality of steamed bread was different in KSSB and NSCSB.About 90%of variability in the height and volume of KSSB could be predicted from protein content,mixing tolerance of Mixograph,average particle size of flour,final viscosity and solvent retention capacity.Protein content and quality parameters also could explain the variation of steamed bread height in NSCSB.Korean wheat carrying Glu-A3c allele produced higher volume of steamed bread(704.7 mL)than Glu-A3d allele(645.8 mL)in KSSB,although there was no significant difference in volume of NSCSB by glutenin compositions.Glu-D1d and Glu-A3c alleles had softer texture of crumb than Glu-D1f and Glu-A3d alleles in KSSB,Glu-B3i allele also showed lower hardness of crumb than their counterpart allele in NSCSB.Hard wheat showed higher height and volume of steamed bread,and lower stress relaxation and hardness of crumb than soft wheat in KSSB.展开更多
The objective of this study was to investigate variation and trends in dough rheological properties and flour quality traits in 330 Chinese wheat varieties. The dough rheological properties of development time(DT), st...The objective of this study was to investigate variation and trends in dough rheological properties and flour quality traits in 330 Chinese wheat varieties. The dough rheological properties of development time(DT), stability time(ST), and farinograph quality number(FQN)were evaluated, as well as the flour quality traits of protein(PC), wet gluten content(WGC), and sedimentation value(SV). The coefficients of variation of DT(40.5%), ST(58.1%), and FQN(42.4%) were higher than those of PC(9.1%), WGC(10.1%), and SV(15.3%). Normal distributions were observed for the flour quality indices but not for the rheological parameters. SV was strongly correlated with the three rheological parameters and accordingly might be used as a primary indicator for dough rheological property evaluation. Our results showed that there has been marked improvement in dough rheological properties for Chinese wheat varieties released since 1986, while flour quality has remained stable.展开更多
Objective To observe the different impacts of electrolytic iron, FeSO4, and NaFeEDTA on body iron store of anemic school students. Methods Four hundreds anemic students at the age of 11-18 years were divided into four...Objective To observe the different impacts of electrolytic iron, FeSO4, and NaFeEDTA on body iron store of anemic school students. Methods Four hundreds anemic students at the age of 11-18 years were divided into four groups. Of which, three consumed different iron fortificants from wheat flour as food vehicle for six months and one consumed non-fortified flour (control). The fortification level of electrolytic iron, FeSO4, and NaFeEDTA was 60 mg Fe/kg, 30 mg Fe/kg, and 20 mg Fe/kg, respectively. Blood samples were collected at 0, 2, 4, and 6 months and hemoglobin (Hb), serum ferritin (SF), and transferrin receptor (TfR) were measured. Results The hemoglobin levels in three intervention groups increased, the increments of Hb in the NaFeEDTA group were significantly higher than that in the other groups. SF and TfR levels increased in the tested groups and body iron store in the NaFeEDTA group was higher than that in the other groups. These parameters did not show any significant changes in the control group. Conclusion NaFeEDTA and FeSO4 tortified wheat flour has positive impacts on iron status in anemic students and NaFeEDTA is more effective than FeSO4, while electrolytic iron is less effective in improving iron store in anemic students.展开更多
The effects of the basal and top-dressing nitrogen (N) on N uptake and translocation, N utilization efficiency, grain yieldand quality of medium-gluten winter wheat Yangmai 10 were studied from 2000 to 2002. The main ...The effects of the basal and top-dressing nitrogen (N) on N uptake and translocation, N utilization efficiency, grain yieldand quality of medium-gluten winter wheat Yangmai 10 were studied from 2000 to 2002. The main results were as follows.Nitrogen content and nitrogen accumulation in plant at maturity increased with the amount of N application. Grain proteincontent and wet gluten content were significantly correlated with applied N. There was a significantly positive correlationbetween nitrogen accumulation before anthesis (NBA) and basal N fertilizer, and between nitrogen accumulation afteranthesis (NAA) and top-dressing N. N accumulated in grains was significantly correlated to NBA, NAA and N translocationfrom vegetative organs after anthesis (NTVA). NBA was significantly correlated with N application, but NAA and NTVAhad a quadratic curve correlation with applied N. N fertilizer use efficiency (NUE) had a quadratic curve correlation withapplied N, and the NUE was high when basal and top-dressing N was equally applied. For the medium-gluten wheatYangmai 10 under the same N application ratio, there was a N-regulating effect when the N application was less than266.55 kg ha-1, a stagnation of yield and quality when N application ranged from 266.55 to 309.08 kg ha-1, and an excessiveN application when the N application rate was greater than 309.08 kg ha-1. Under the conditions of this experiment, theprecise N application is 220-270 kg ha-1 with basal and top-dressing N equally used when a grain yield of more than 6 750kg ha-1, protein content higher than 12%, wet gluten content more than 30% and NUE greater than 40% could be obtained.展开更多
A laboratory experiment has been designed and implemented to study the effects of storage temperatures (27.5°C and 37.5°C) and storage periods (day, 3 days, 10 days, 20 days and 30 days) in normal conditions...A laboratory experiment has been designed and implemented to study the effects of storage temperatures (27.5°C and 37.5°C) and storage periods (day, 3 days, 10 days, 20 days and 30 days) in normal conditions and relative humidity on the characteristics of wheat flour quality, as well as some of the chemical characteristics of flour (moisture content and ratio of wet gluten), the physical properties (color and falling number). Increasing the storage temperature from 27.5°C to 37.5°C has led to decreasing moisture content of flour stored under storage relative humidity of 38% - 70%. It has also resulted in extending the storage period from 1 day to 10 days to a decrease in moisture content of flour, and this decline has increased the storage period up to thirty days. The overlap between these two factors has been significantly affective. As the storage temperature of flour increased from 27.5°C to 37.5°C, the percentage of wet gluten has been increased too, and the storage period was extended to ten days. This has led to a significant increase in the percentage of wet gluten flour. In addition, there was a significant response to the effective overlap between the storage temperatures and periods of storage under study in this manner. Increasing the storage temperature from 27.5°C to 37.5°C has led to significantly increased values of the color of the stored flour. Besides, increasing the storage period one day more has led to decreasing the values of the color of the stored flour. However, there has been no significant change to the subsequent periods of storage. The overlap between both factors of temperature and storage periods has a significant effect on the flour color. There has been a significant decrease of the enzyme activity (the height values of the falling No.). But there is a noticeable increase to the falling No. values of the stored flour by 37.5°C when increasing the storage periods from one day to ten days and thirty days. This effect, nonetheless, has not reached the significant level.展开更多
Pastry is an essential part of food stuff people like, especially preferring those made of wheat flour: cakes, biscuits, pancakes, etc. The nutritive value of the products mentioned above is not high. Therefore, there...Pastry is an essential part of food stuff people like, especially preferring those made of wheat flour: cakes, biscuits, pancakes, etc. The nutritive value of the products mentioned above is not high. Therefore, there is a need to increase it by adding something like doum fruit (Hyphaene thebaica L.), which is a widespread in Upper Egypt. Doum fruit is a rich source of fibers and antioxidants, also other valuable substances such as carbohydrates and minerals especially potassium (K for people suffering from blood pressure problems). This investigation was carried out to study the possibility of utilization doum fruit powder in cake production. Five levels of wheat flour substitution were used 0%, 5%, 10%, 15% and 20% to produce cake. Also, the effects of blends on farinograph parameters were studied. Results indicated that substitution of doum powder (D.P) led to increase the water absorption (%) and dough weakening (B.U), whereas dough stability (min) was decreased. The water holding capacity of blends increased with increasing the level of substitution. The chemical, physical and sensory characteristics of the prepared cakes were studied. Results showed that increasing the levels of substitution increased the total fat, crude fiber and ash contents in produced cake compared with control. Minerals of the produced cake showed an increment in K and Mg, while slightly increment in Ca, Fe and Zn with increasing the level of substitution. Total phenol and antioxidant activity (AO) increased in substituted cake. Physical attributes of the produced cakes were evaluated and results showed that volume of substituted cakes decreased with increasing the level of replacement except for 10% level it increased. Results of textural analysis showed that D.P fiber decreased all the parameters. Concerning cake color, as the percentage of D.P increased, the color of the cake became darker and had high a and b values. The sensory evaluation results showed an insignificantly decrease in the acceptability by increasing the doum powder substitution comparing with control.展开更多
The study presents the effect of utilizing wheat, soy and moringa leaf flour and quality analysis of the flour. The composite flour was prepared using refined wheat flour, soy flour and moringa leaf flour. Four compos...The study presents the effect of utilizing wheat, soy and moringa leaf flour and quality analysis of the flour. The composite flour was prepared using refined wheat flour, soy flour and moringa leaf flour. Four composite flour, compositions were formulated such as 100% wheat flour (control) designated as sample A. Sample B consisted of 75% wheat, 20% soybean and 5% moringa leaf. Sample C consisted of 70% wheat, 20% soybean and 10% moringa leaf. Sample D was 65% wheat, 20% soybean and 15% moringa leaf. Sample E was 60% wheat, 20% soybean and 20% moringa leaf, respectively. Proximate, chemical, and functional properties of wheat, soy and moringa leaf flours were studied in composite flour variation and preparations. The present study highlighted the nutrients enrichment of flour on incorporation of soy and moringa leaf. Relevant statistical tests were done to analyse the significance of means for all tested parameters. Composite flour composition with 20% soybean was identified to produce optimal nutrient, mineral quality and yield. The addition of soybean and moringa flour in baked products has been shown in this study to improve the nutrition and health benefits of the body. It also serves as a good cut on the cost of wheat importation in communities with supply challenges.展开更多
The economic losses and the health hazards of the mycotoxins produced by spoilage fungi are the main concerns of the food industry. The spoilage of bakery products by fungi is more common in countries with a high humi...The economic losses and the health hazards of the mycotoxins produced by spoilage fungi are the main concerns of the food industry. The spoilage of bakery products by fungi is more common in countries with a high humidity and temperature. About 5-10% of food production is spoiled by the growth of yeast and fungi in food materials. Similarly, in Western Europe, the growth of the spoilage fungi of bread is estimated to reach more than 200 million Euros per year. The history conditions of the food can be a major factor in determining any fungal spoilage--for example, stored and processed foods are more sensitive to spoilage when compared with fresh and prepared foods. Lactic acid bacteria isolated from Bulgarian wheat and rye flour were used in the present study to check their antifungal properties against pathogenic yeast and fungi imperfecta using standard disc diffusion method in vitro. A broad spectrum of antifungal activity of the six newly identified as L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6 was estimated. Our in vitro studies were performed with wheat and rye sourdough, in order to simulate a real product and to assess the bio-protective potential of the tested lactobacilli. The used test-cultures are representatives of carcinogenic, toxigenic, deteriorative and allergenic fungi from the genera .4spergillus and Penicillium. The all tested strains completely suppress the growth of against C. glabrata 72. Strains L. plantarum Tsl and Ts3 completely suppress the growth against S. cerevisae. While, in the sample with L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6, a retarded and weak growth of A. niger and P. claviforme was observed. However, the spore germination and the colony growth started only on the fifth day of the mould lactobacilli co-cultivation, which also should be considered as a good result. In this study six isolates Tsl,Ts2, Ts3, Ts4, Ts5 and Ts6, from the traditional Bulgarian wheat and rye flour have been identified as L. plantarum and L. helveticus and characterized as cultures with promising antifungal activity. Obtained results from the combined molecular identification (16S rRNA gene sequencing) approach contribute to give new data on the microbial biodiversity of this not well-studied niche. The antifungal activity of our new isolates, identified as L. plantarum and L. helveticus, seems to be a promising advantage of these six strains, suggesting their potential applications in different food technologies. However, more experiments have to be conducted to clarify the nature and the mechanisms of the reported antifungal activity and they are still in progress. The combination of dairy origin and strong inhibitory activity of the lactobacillus strains is a prerequisite for their possible application as starters and/or bioprotective antifungal adjuncts.展开更多
The feasibility of partially replacing wheat flour with malted rice flour in bread making was evaluated in several formulations, aiming to find a formulation for the production of malted rice-wheat bread with better n...The feasibility of partially replacing wheat flour with malted rice flour in bread making was evaluated in several formulations, aiming to find a formulation for the production of malted rice-wheat bread with better nutritional quality and consumer acceptance. The whole grains of a local rice variety (Oryza sativa L. subsp. indica var. Mottaikaruppan) were steeped in distilled water (12 h, 30°C) and germinated for 3 days to obtain high content of soluble materials and amylase activity in bread making. The quality of bread was evaluated by considering the physical and sensorial parameters. When the wheat flour was substituted with malted rice flour, 35% substitution level and the malted rice flour from 3 days of germination was the best according to the physical and sensory qualities of bread. The quality of bread was improved by the addition of 20 g of margarine, 20 g of baking powder and 20 g of yeast in 1 kg of flour. Among different ratios of yeast and baking powder, 2:1 was the best. Bread improver containing amylases and oxidizing agents at the concentration of 40 g/kg was selected as the best concentration. When comparing the final formulation made in the bakery with wheat bread, malted rice-wheat bread contains more soluble dietary fiber (0.62%), insoluble dietary fiber (3.95%), total dietary fiber (4.57%) and free amino acid content (0.64 g/kg) than those in wheat bread (0.5%, 2.73%, 3.23% and 0.36 g/kg, respectively).展开更多
Mixtures of refined wheat flour (RWF) with flours from different sources could impact the functional qualities and shelf life of wheat-based products. Storage stability is one of the most critical factors for tortilla...Mixtures of refined wheat flour (RWF) with flours from different sources could impact the functional qualities and shelf life of wheat-based products. Storage stability is one of the most critical factors for tortilla quality. Tortillas made from yam (Dioscorea sp.) wheat composite flours were characterized. RWF was substituted with 5%, 10%, 15%, and 20% of fermented yam flour-brown (FYF) and unfermented yam flour-white (UYF). Farinograph water absorptions of UYF-composite flours (65.5% - 77.1%) were significantly (P < 0.05) higher than FYF-composite flour absorptions (60.5% - 61.5%). During storage, moisture contents of composite flour tortillas increased while the RWF-tortilla decreased. Tortilla from FYF-composite flour exhibited greater strength (3.1 N at day zero on average) compared to UYF-composite tortillas (2.1 N at day zero on average), while UYF-composite flour tortillas had good extensibility and rollability properties. The properties and composition type and ratios of flour blends affected tortilla quality during the storage period. The substitution of RWF with 15% or 20% UYF would be more suitable for making tortilla with improved properties compared to that of FYF.展开更多
The profit margin in the flour milling industry is quite narrow,so high-quality raw materials and efficiency of milling operations are crucial for every company. Many flour mills,especially those which import wheat fr...The profit margin in the flour milling industry is quite narrow,so high-quality raw materials and efficiency of milling operations are crucial for every company. Many flour mills,especially those which import wheat from other countries and have limited storage space for the different varieties or classes of wheat,can not afford to buy low quality wheat. Consequently,a mathematical model which can test the impact and interactions of raw materials,in technical point of view,would be a useful decision-making tool for the milling industry. A flour miller tests wheat for physical and chemical characteristics,cleanness and soundness. The miller also performs experimental milling,if available,to have some idea how the given wheat will behave during commercial milling. Based on these test results,the miller can only guess the commercial milling results such as flour yields and flour ash and protein contents. Thus,the objective of this study was to develop empirical equations to estimate commercial milling results,using the physical,chemical and experimental milling data of the given wheat blend and also,additionally,flour ash and protein specifications of the end-user. This was done by using the actual commercial milling procedures and their wheat physical,chemical,experimental milling data,and other vital data. Data were collected from a commercial mill located in East Asia that had four production lines and used wheat blend combinations from five different wheat classes,i.e. Hard Red Winter (HRW),Dark Northern Spring (DNS),Soft White (SW),Australian Soft (AS),and Australian Standard White (ASW) wheat to produce over 40 different products. The wheat physical and chemical characteristics included test weight,thousand kernel weight,ash and protein contents. The experimental milling data were straight-grade and patent flour yields,along with patent flour ash and protein contents from a Buhler experimental mill. The commercial milling results included the flour yields of patent,first clear,and second clear flours,as well as the ash and protein contents of commercial patent flours. Using multiple linear regression procedures,we have developed empirical equations to be able to estimate the commercial patent flour yields with R2 values above 0.90 for all four production lines,and commercial first clear flour yields with R2 values ranging 0.76 to 0.98,and the commercial patent flour protein contents with R2 values of 0.89 to 0.92. However,the yields of commercial second clear flours and the commercial patent flour ash contents were not able to be estimated with high coefficients of determination (R2 values). We recommend that the empirical equations for estimating commercial milling parameters should be derived using data from each individual flour milling company,for each production line of a given mill,and furthermore,tailored to specific products at a given ash and/or protein contents desired by end-users.展开更多
The objective of this research was to investigate the effect of Malva nut gum (MG) replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and free...The objective of this research was to investigate the effect of Malva nut gum (MG) replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and freeze-thaw stability of different flours incorporated with 0, 0.5%, 1%, 2%, 3% and 5% of MG were investigated. Pasting temperature (60 ℃-87 ℃) of the pastes significantly decreased with increasing of MG content for wheat and rice flours, but had no significant effect for waxy rice flour. Incorporation of MG into all flours significantly elevated the peak viscosity by about 0.9-2.6 folds when compared to non-MG samples. Hot paste viscosity, breakdown and final viscosity for all flour mixtures significantly increased with increasing of MG which ranged from 81-427, 37-559 and 152-463 RVU, respectively. Freeze-thaw stability measurement demonstrated that higher level of MG in wheat and rice gel mixtures could decrease syneresis. However, MG had no effect on syneresis of waxy rice gel. Presence of MG in flours alters the pasting properties and syneresis effect. It is suggested that higher viscosity and lower syneresis of gels could be modified by MG.展开更多
Many persons worldwide are deficient in micronutrients, two of the most common being vitamin A and iron. Fortification of staple food is a commonly used and effective method of boosting micronutrient intake. Wheat flo...Many persons worldwide are deficient in micronutrients, two of the most common being vitamin A and iron. Fortification of staple food is a commonly used and effective method of boosting micronutrient intake. Wheat flour is widely used around the world and makes a good vehicle for fortification, but there is a lack of studies on the storage stability of fortified wheat flour. In this study, we fortified wheat flour with elevated levels of vitamin A and three sources of iron and stored it for up to 16 weeks at refrigerated or room temperature or elevated temperature. The rate of disappearance of vitamin A was monitored by high pressure liquid chromatography, and the rate of disappearance was fotmd to be directly proportional to the duration of storage and storage temperature. Higher temperatures contributed to greater loss of vitamin A. Iron, regardless of source, did not play a major role in contributing to the rate of vitamin A loss. Flour functionality was assessed by baking loaves of bread from the stored flour and assessing physical properties as well as subjecting the loaves to an expert sensory panel. Functionality also changed with time and temperature of storage, but sensory analysis found that these changes were not detrimental to the quality of bread baked from the stored flours. Trained sensory panelists found that breads baked from flours fortified with ferrous sulfate and stored at the three temperatures for times up to eight weeks were markedly different from fortified flours using hydrogen reduced irons.展开更多
The objective of this research is to investigate the impact of infestation by the confused flour beetle Tribolium confusum on the specification of flour and its product. The results of this work showed that infestatio...The objective of this research is to investigate the impact of infestation by the confused flour beetle Tribolium confusum on the specification of flour and its product. The results of this work showed that infestation by the confused flour beetle with 5 pairs of adult stage and its progeny within 3 months period may cause high deterioration and damaged of the flour specification. The people in lraq get their flour from some official and non-official mills which they produce not so good quality of this flour in addition to which it contains some times an infestation with the two species of the flour beetles T. castaneum and T. confusum, when people do not use this quantity as quickly as possible during this period of storage, the beetles will be increased in numbers and make the flour unacceptable for any kind of pastes or bread. The infestation by this beetle causes great pollution to the flour by the ecdysial of larvae and a bad smell that it leaves on the flour and all its products.展开更多
Samples of 12 hard winter wheats and their flours that produced breads varying in crumb grain scores were studied for 38 quality parameters including: wheat physical and chemical characteristics; flour ash and protein...Samples of 12 hard winter wheats and their flours that produced breads varying in crumb grain scores were studied for 38 quality parameters including: wheat physical and chemical characteristics; flour ash and protein contents,starch damage,swelling power,pasting characteristics,and flour particle size distribution; dough properties determined by a mixograph; and breadmaking properties for pup loaves (100g flour). Only two parameters,the protein content of wheat and the granulation of flour,showed significant correlations with bread crumb grain scores. Protein content of wheat ranging 12.9%~14.5% determined by an NIR method showed a weak inverse relationship (r =-0.61,p<0.05) with bread crumb grain score. Flour particle size distribution measured by both Alpine Air Jet Sieve and NIR methods revealed that the weight wt % of particles less than 38μm in size and representing 9.6%~19.3% of the flour weights was correlated positively (r =0 .78,p<0.01) with crumb grain score,whereas wt % of flour particles larger than 125μm had an inverse relationship (r =-0.60,p<0.05) with crumb grain score.展开更多
Wheat/hemp and wheat/teff model composites were prepared as 90:10 and 80:20 w/w blends, using two different Czech commercial wheat flour samples (standards M, M1) and bright/dark forms of these non-traditional crops f...Wheat/hemp and wheat/teff model composites were prepared as 90:10 and 80:20 w/w blends, using two different Czech commercial wheat flour samples (standards M, M1) and bright/dark forms of these non-traditional crops flour. The objective of this study was to determine the effect of alternative flour samples on the blend compositional profiles including dietary fibre content, on the technological quality described by modern Solvent Retention Capacity method and on laboratory baking test results. According to seeds composition, nutritional flour enrichment reached higher levels of protein (from approx. 13.0% about 30% vs. 6%) and fibre contents (from approx. 3.3% about 50% vs. 30%) in the case of hemp and teff samples. In terms of the SRC profile, the qualitatively better sample M was weakened by hemp flour additions, while somewhat worse sample M1 was improved by teff flour additions. Results from the baking test showed that the hemp composites were partly dependent on hemp flour form. Volumes of bread with bright hemp were diminished from 257 mL/100g up to 196 mL/100g, the products containing dark hemp increased up to 328 mL/100g. Teff-fortified bun volumes were evaluated in close range of 325 - 369 mL/100g against 381 mL/100g for standard M1. Sensorial score of wheat/hemp breads were worse owing to spicy taste and fatty aftertaste, while hay-like by-taste in wheat/teff bread could be tolerable of 10% in recipe.展开更多
基金National Natural Science Foundation of China(30560078)Funds for Doctors of Corps(05JC02)+2 种基金National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2006BAD01A02-30)Key Science and Technology Program of Corps(2011BA002)Youth Foundation of Xinjiang Academy of Agri-Reclamation Sciences(YQJ201102)~~
文摘In the research,36 spring wheat cultivars from Xinjiang were used to investigate flour yield,ash content,color,granularity,flour quality,paste quality and gelatinization property and to evaluate processing quality and characters of stretched noodle,in order to explore relationship of milling flour quality with quality property of Xinjiang spring wheat and with processing quality of Xinjiang hand-stretched noodle,which provides theoretical references for improvement of Xinjiang spring wheat cultivars,breeding of specific cultivars(for Xinjiang stretched noodles),and advancement of stretched noodles.The results indicated that flour color is dominant among flour quality properties of Xinjiang spring wheat,which is of significant correlation with processing quality of stretched noodles.Therefore,in quality improvement of Xinjiang stretched noodles,flour yield of Xinjiang wheat should be enhanced and ash content and damaged starch should be reduced in order to improve quality of flour and stretched noodles from Xinjiang spring wheat.The indices of milling flours for Xinjiang stretched noodles are as follows:flour yield ≥60.77%,ash content ≤ 0.45%,damaged starch≤3.77%,granularity ≤108.14%,brightness(L^*)≥ 90.86,redness(a^*)≥-0.82,and yellowness(b^*) ≤9.00.
基金the National Natural Science Foundation of China (30671270)the National High Technology R & D Program of China (2006AA100101).
文摘Resistant starch (RS) is the undigested starch that passes through the small intestine to the large intestine. As a functional low calorie additive, it has special applications in the food industry. Rapid visco analysis (RVA) and the Brabender farinograph were used to study the pasting properties and the viscoelasticity of blends of RS (RS3 and RS2) and three wheat flours. The wheat flours represented strong gluten wheat (SGW), intermediate gluten wheat (IGW), and weak gluten wheat (WGW) flours, at different levels of RS substitution (0, 5, 10, 15, and 20%). The influence of RS3 on the control wheat flours and RS-wheat flour blends were consistent with those of RS2. The peak, trough, and final viscosities of RS3-wheat flour blends were higher than those of the corresponding RS2-wheat flour blends. The peak, trough, breakdown, final, and setback viscosities ofwheat-RS blends decreased with an increase in resistant starch contents from 0 to 20% in the blends. The 0-20% RS-wheat flour blends were all able to form doughs. The dough development times, dough stabilities, dough breakdown times, and farinograph quality numbers for the RS-wheat flour blends decreased as the RS proportion in the blends increased. The values for RS-SGW flour blends were the highest, followed by RS-IGW and then RS-WGW flour blends. The water absorption values for RS-wheat flour blends and the mixing tolerance index for RS-WGW flour blends were found to increase significantly with an increasing proportion of RS from 0 to 20%, but the mixing tolerance index for RS-SGW and RS-IGW flour blends showed no significant differences amongst the different ratios. Correlation analysis showed that the Farinograph quality number was highly positively correlated with dough breakdown time, dough stability, and dough development time (r= 1.000, 0.958, 0.894), and highly negatively correlated with the mixing tolerance index (r =-0.890). Data from this study can be used for the development of dough-based products. It also provides a basis for RS-wheat flour blends and quality evaluation in the food industry.
基金support was provided bythe National Basic Research Program of China (973Program, 2009CB118301)the National Natural Sci-ence Foundation of ChinaNational High-Tech R&D Program of China (863 Program, 2006AA10Z1E9)
文摘The phytic acid contents of eight fractions of wheat flours from different mill streams and those in wheat brans, which were separated by different sieves into various sizes, were determined and analyzed. A rapid method for phytic acid assay by adding thioglycolic acid (mercapto acetic acid) with 2,2-bipyridine was used, with an acidic iron-Ⅲ-solution of known iron content. The amount ofphytate was indicated by the decrease in iron in the supernatant. Significant differences were observed in phytic acid content among different milling streams and different cultivars (P〈0.05). On an average, coarse bran had the highest phytic acid content (53.85 mg g^-1), and the shorts had 28.48 mg g^-1. The B5 break flour had a higher phytic acid content (4.8 mg g^-1) than the B7 (2.75 mg g^-1) and B8 (2.03 mg g^-1) reduction flours. Lower values were found in the B3, B6 and B7 flours (1.07, 0.79, and 0.76 mg g^-1, respectively). The phytic acid contents of bran decreased with smaller bran sizes, ranging from 54 to 5.09 mg g^-1.
基金the support of Cooperative Research Program for Agriculture Science & Technology Development (PJ01246404)Rural Development Administration, Republic of Korea
文摘The purpose of this study is to identify major factors affecting the manufacture and quality of steamed bread,consumed in Southeast Asia including China,Japan,and Korea.Hence,flours of 11 Korean wheat cultivars were used to evaluate quality attributes of two different styles of steamed bread,Korean style steamed bread(KSSB)and northern-style Chinese steamed bread(NSCSB).KSSB prepared more ingredients and higher optimum water absorption of dough than NSCSB because Korean consumers prefer white and glossy surface and soft crumb.KSSB showed lower height,larger diameter and volume of steamed bread,higher stress relaxation,and softer texture of crumb than NSCSB.The correlation between flour characteristics and quality of steamed bread was different in KSSB and NSCSB.About 90%of variability in the height and volume of KSSB could be predicted from protein content,mixing tolerance of Mixograph,average particle size of flour,final viscosity and solvent retention capacity.Protein content and quality parameters also could explain the variation of steamed bread height in NSCSB.Korean wheat carrying Glu-A3c allele produced higher volume of steamed bread(704.7 mL)than Glu-A3d allele(645.8 mL)in KSSB,although there was no significant difference in volume of NSCSB by glutenin compositions.Glu-D1d and Glu-A3c alleles had softer texture of crumb than Glu-D1f and Glu-A3d alleles in KSSB,Glu-B3i allele also showed lower hardness of crumb than their counterpart allele in NSCSB.Hard wheat showed higher height and volume of steamed bread,and lower stress relaxation and hardness of crumb than soft wheat in KSSB.
基金supported by the Science and Technology Innovation Project of CAAS for Wang Tianyu (Crop Germplasm Resources Identification and Discovery)
文摘The objective of this study was to investigate variation and trends in dough rheological properties and flour quality traits in 330 Chinese wheat varieties. The dough rheological properties of development time(DT), stability time(ST), and farinograph quality number(FQN)were evaluated, as well as the flour quality traits of protein(PC), wet gluten content(WGC), and sedimentation value(SV). The coefficients of variation of DT(40.5%), ST(58.1%), and FQN(42.4%) were higher than those of PC(9.1%), WGC(10.1%), and SV(15.3%). Normal distributions were observed for the flour quality indices but not for the rheological parameters. SV was strongly correlated with the three rheological parameters and accordingly might be used as a primary indicator for dough rheological property evaluation. Our results showed that there has been marked improvement in dough rheological properties for Chinese wheat varieties released since 1986, while flour quality has remained stable.
基金supported by the Center for Health Promotion, International Life Sciences Institute
文摘Objective To observe the different impacts of electrolytic iron, FeSO4, and NaFeEDTA on body iron store of anemic school students. Methods Four hundreds anemic students at the age of 11-18 years were divided into four groups. Of which, three consumed different iron fortificants from wheat flour as food vehicle for six months and one consumed non-fortified flour (control). The fortification level of electrolytic iron, FeSO4, and NaFeEDTA was 60 mg Fe/kg, 30 mg Fe/kg, and 20 mg Fe/kg, respectively. Blood samples were collected at 0, 2, 4, and 6 months and hemoglobin (Hb), serum ferritin (SF), and transferrin receptor (TfR) were measured. Results The hemoglobin levels in three intervention groups increased, the increments of Hb in the NaFeEDTA group were significantly higher than that in the other groups. SF and TfR levels increased in the tested groups and body iron store in the NaFeEDTA group was higher than that in the other groups. These parameters did not show any significant changes in the control group. Conclusion NaFeEDTA and FeSO4 tortified wheat flour has positive impacts on iron status in anemic students and NaFeEDTA is more effective than FeSO4, while electrolytic iron is less effective in improving iron store in anemic students.
基金supported by Foundation for University Key Teacher by the Ministry of Education of China(GG-901-11117-1003)the Research Fund from Jiangsu Province of China(BE2001333).
文摘The effects of the basal and top-dressing nitrogen (N) on N uptake and translocation, N utilization efficiency, grain yieldand quality of medium-gluten winter wheat Yangmai 10 were studied from 2000 to 2002. The main results were as follows.Nitrogen content and nitrogen accumulation in plant at maturity increased with the amount of N application. Grain proteincontent and wet gluten content were significantly correlated with applied N. There was a significantly positive correlationbetween nitrogen accumulation before anthesis (NBA) and basal N fertilizer, and between nitrogen accumulation afteranthesis (NAA) and top-dressing N. N accumulated in grains was significantly correlated to NBA, NAA and N translocationfrom vegetative organs after anthesis (NTVA). NBA was significantly correlated with N application, but NAA and NTVAhad a quadratic curve correlation with applied N. N fertilizer use efficiency (NUE) had a quadratic curve correlation withapplied N, and the NUE was high when basal and top-dressing N was equally applied. For the medium-gluten wheatYangmai 10 under the same N application ratio, there was a N-regulating effect when the N application was less than266.55 kg ha-1, a stagnation of yield and quality when N application ranged from 266.55 to 309.08 kg ha-1, and an excessiveN application when the N application rate was greater than 309.08 kg ha-1. Under the conditions of this experiment, theprecise N application is 220-270 kg ha-1 with basal and top-dressing N equally used when a grain yield of more than 6 750kg ha-1, protein content higher than 12%, wet gluten content more than 30% and NUE greater than 40% could be obtained.
文摘A laboratory experiment has been designed and implemented to study the effects of storage temperatures (27.5°C and 37.5°C) and storage periods (day, 3 days, 10 days, 20 days and 30 days) in normal conditions and relative humidity on the characteristics of wheat flour quality, as well as some of the chemical characteristics of flour (moisture content and ratio of wet gluten), the physical properties (color and falling number). Increasing the storage temperature from 27.5°C to 37.5°C has led to decreasing moisture content of flour stored under storage relative humidity of 38% - 70%. It has also resulted in extending the storage period from 1 day to 10 days to a decrease in moisture content of flour, and this decline has increased the storage period up to thirty days. The overlap between these two factors has been significantly affective. As the storage temperature of flour increased from 27.5°C to 37.5°C, the percentage of wet gluten has been increased too, and the storage period was extended to ten days. This has led to a significant increase in the percentage of wet gluten flour. In addition, there was a significant response to the effective overlap between the storage temperatures and periods of storage under study in this manner. Increasing the storage temperature from 27.5°C to 37.5°C has led to significantly increased values of the color of the stored flour. Besides, increasing the storage period one day more has led to decreasing the values of the color of the stored flour. However, there has been no significant change to the subsequent periods of storage. The overlap between both factors of temperature and storage periods has a significant effect on the flour color. There has been a significant decrease of the enzyme activity (the height values of the falling No.). But there is a noticeable increase to the falling No. values of the stored flour by 37.5°C when increasing the storage periods from one day to ten days and thirty days. This effect, nonetheless, has not reached the significant level.
文摘Pastry is an essential part of food stuff people like, especially preferring those made of wheat flour: cakes, biscuits, pancakes, etc. The nutritive value of the products mentioned above is not high. Therefore, there is a need to increase it by adding something like doum fruit (Hyphaene thebaica L.), which is a widespread in Upper Egypt. Doum fruit is a rich source of fibers and antioxidants, also other valuable substances such as carbohydrates and minerals especially potassium (K for people suffering from blood pressure problems). This investigation was carried out to study the possibility of utilization doum fruit powder in cake production. Five levels of wheat flour substitution were used 0%, 5%, 10%, 15% and 20% to produce cake. Also, the effects of blends on farinograph parameters were studied. Results indicated that substitution of doum powder (D.P) led to increase the water absorption (%) and dough weakening (B.U), whereas dough stability (min) was decreased. The water holding capacity of blends increased with increasing the level of substitution. The chemical, physical and sensory characteristics of the prepared cakes were studied. Results showed that increasing the levels of substitution increased the total fat, crude fiber and ash contents in produced cake compared with control. Minerals of the produced cake showed an increment in K and Mg, while slightly increment in Ca, Fe and Zn with increasing the level of substitution. Total phenol and antioxidant activity (AO) increased in substituted cake. Physical attributes of the produced cakes were evaluated and results showed that volume of substituted cakes decreased with increasing the level of replacement except for 10% level it increased. Results of textural analysis showed that D.P fiber decreased all the parameters. Concerning cake color, as the percentage of D.P increased, the color of the cake became darker and had high a and b values. The sensory evaluation results showed an insignificantly decrease in the acceptability by increasing the doum powder substitution comparing with control.
文摘The study presents the effect of utilizing wheat, soy and moringa leaf flour and quality analysis of the flour. The composite flour was prepared using refined wheat flour, soy flour and moringa leaf flour. Four composite flour, compositions were formulated such as 100% wheat flour (control) designated as sample A. Sample B consisted of 75% wheat, 20% soybean and 5% moringa leaf. Sample C consisted of 70% wheat, 20% soybean and 10% moringa leaf. Sample D was 65% wheat, 20% soybean and 15% moringa leaf. Sample E was 60% wheat, 20% soybean and 20% moringa leaf, respectively. Proximate, chemical, and functional properties of wheat, soy and moringa leaf flours were studied in composite flour variation and preparations. The present study highlighted the nutrients enrichment of flour on incorporation of soy and moringa leaf. Relevant statistical tests were done to analyse the significance of means for all tested parameters. Composite flour composition with 20% soybean was identified to produce optimal nutrient, mineral quality and yield. The addition of soybean and moringa flour in baked products has been shown in this study to improve the nutrition and health benefits of the body. It also serves as a good cut on the cost of wheat importation in communities with supply challenges.
文摘The economic losses and the health hazards of the mycotoxins produced by spoilage fungi are the main concerns of the food industry. The spoilage of bakery products by fungi is more common in countries with a high humidity and temperature. About 5-10% of food production is spoiled by the growth of yeast and fungi in food materials. Similarly, in Western Europe, the growth of the spoilage fungi of bread is estimated to reach more than 200 million Euros per year. The history conditions of the food can be a major factor in determining any fungal spoilage--for example, stored and processed foods are more sensitive to spoilage when compared with fresh and prepared foods. Lactic acid bacteria isolated from Bulgarian wheat and rye flour were used in the present study to check their antifungal properties against pathogenic yeast and fungi imperfecta using standard disc diffusion method in vitro. A broad spectrum of antifungal activity of the six newly identified as L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6 was estimated. Our in vitro studies were performed with wheat and rye sourdough, in order to simulate a real product and to assess the bio-protective potential of the tested lactobacilli. The used test-cultures are representatives of carcinogenic, toxigenic, deteriorative and allergenic fungi from the genera .4spergillus and Penicillium. The all tested strains completely suppress the growth of against C. glabrata 72. Strains L. plantarum Tsl and Ts3 completely suppress the growth against S. cerevisae. While, in the sample with L. plantarum strains e Tsl, Ts2, Ts3,Ts4 and Ts5, and L. helveticus Ts6, a retarded and weak growth of A. niger and P. claviforme was observed. However, the spore germination and the colony growth started only on the fifth day of the mould lactobacilli co-cultivation, which also should be considered as a good result. In this study six isolates Tsl,Ts2, Ts3, Ts4, Ts5 and Ts6, from the traditional Bulgarian wheat and rye flour have been identified as L. plantarum and L. helveticus and characterized as cultures with promising antifungal activity. Obtained results from the combined molecular identification (16S rRNA gene sequencing) approach contribute to give new data on the microbial biodiversity of this not well-studied niche. The antifungal activity of our new isolates, identified as L. plantarum and L. helveticus, seems to be a promising advantage of these six strains, suggesting their potential applications in different food technologies. However, more experiments have to be conducted to clarify the nature and the mechanisms of the reported antifungal activity and they are still in progress. The combination of dairy origin and strong inhibitory activity of the lactobacillus strains is a prerequisite for their possible application as starters and/or bioprotective antifungal adjuncts.
文摘The feasibility of partially replacing wheat flour with malted rice flour in bread making was evaluated in several formulations, aiming to find a formulation for the production of malted rice-wheat bread with better nutritional quality and consumer acceptance. The whole grains of a local rice variety (Oryza sativa L. subsp. indica var. Mottaikaruppan) were steeped in distilled water (12 h, 30°C) and germinated for 3 days to obtain high content of soluble materials and amylase activity in bread making. The quality of bread was evaluated by considering the physical and sensorial parameters. When the wheat flour was substituted with malted rice flour, 35% substitution level and the malted rice flour from 3 days of germination was the best according to the physical and sensory qualities of bread. The quality of bread was improved by the addition of 20 g of margarine, 20 g of baking powder and 20 g of yeast in 1 kg of flour. Among different ratios of yeast and baking powder, 2:1 was the best. Bread improver containing amylases and oxidizing agents at the concentration of 40 g/kg was selected as the best concentration. When comparing the final formulation made in the bakery with wheat bread, malted rice-wheat bread contains more soluble dietary fiber (0.62%), insoluble dietary fiber (3.95%), total dietary fiber (4.57%) and free amino acid content (0.64 g/kg) than those in wheat bread (0.5%, 2.73%, 3.23% and 0.36 g/kg, respectively).
文摘Mixtures of refined wheat flour (RWF) with flours from different sources could impact the functional qualities and shelf life of wheat-based products. Storage stability is one of the most critical factors for tortilla quality. Tortillas made from yam (Dioscorea sp.) wheat composite flours were characterized. RWF was substituted with 5%, 10%, 15%, and 20% of fermented yam flour-brown (FYF) and unfermented yam flour-white (UYF). Farinograph water absorptions of UYF-composite flours (65.5% - 77.1%) were significantly (P < 0.05) higher than FYF-composite flour absorptions (60.5% - 61.5%). During storage, moisture contents of composite flour tortillas increased while the RWF-tortilla decreased. Tortilla from FYF-composite flour exhibited greater strength (3.1 N at day zero on average) compared to UYF-composite tortillas (2.1 N at day zero on average), while UYF-composite flour tortillas had good extensibility and rollability properties. The properties and composition type and ratios of flour blends affected tortilla quality during the storage period. The substitution of RWF with 15% or 20% UYF would be more suitable for making tortilla with improved properties compared to that of FYF.
文摘The profit margin in the flour milling industry is quite narrow,so high-quality raw materials and efficiency of milling operations are crucial for every company. Many flour mills,especially those which import wheat from other countries and have limited storage space for the different varieties or classes of wheat,can not afford to buy low quality wheat. Consequently,a mathematical model which can test the impact and interactions of raw materials,in technical point of view,would be a useful decision-making tool for the milling industry. A flour miller tests wheat for physical and chemical characteristics,cleanness and soundness. The miller also performs experimental milling,if available,to have some idea how the given wheat will behave during commercial milling. Based on these test results,the miller can only guess the commercial milling results such as flour yields and flour ash and protein contents. Thus,the objective of this study was to develop empirical equations to estimate commercial milling results,using the physical,chemical and experimental milling data of the given wheat blend and also,additionally,flour ash and protein specifications of the end-user. This was done by using the actual commercial milling procedures and their wheat physical,chemical,experimental milling data,and other vital data. Data were collected from a commercial mill located in East Asia that had four production lines and used wheat blend combinations from five different wheat classes,i.e. Hard Red Winter (HRW),Dark Northern Spring (DNS),Soft White (SW),Australian Soft (AS),and Australian Standard White (ASW) wheat to produce over 40 different products. The wheat physical and chemical characteristics included test weight,thousand kernel weight,ash and protein contents. The experimental milling data were straight-grade and patent flour yields,along with patent flour ash and protein contents from a Buhler experimental mill. The commercial milling results included the flour yields of patent,first clear,and second clear flours,as well as the ash and protein contents of commercial patent flours. Using multiple linear regression procedures,we have developed empirical equations to be able to estimate the commercial patent flour yields with R2 values above 0.90 for all four production lines,and commercial first clear flour yields with R2 values ranging 0.76 to 0.98,and the commercial patent flour protein contents with R2 values of 0.89 to 0.92. However,the yields of commercial second clear flours and the commercial patent flour ash contents were not able to be estimated with high coefficients of determination (R2 values). We recommend that the empirical equations for estimating commercial milling parameters should be derived using data from each individual flour milling company,for each production line of a given mill,and furthermore,tailored to specific products at a given ash and/or protein contents desired by end-users.
文摘The objective of this research was to investigate the effect of Malva nut gum (MG) replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and freeze-thaw stability of different flours incorporated with 0, 0.5%, 1%, 2%, 3% and 5% of MG were investigated. Pasting temperature (60 ℃-87 ℃) of the pastes significantly decreased with increasing of MG content for wheat and rice flours, but had no significant effect for waxy rice flour. Incorporation of MG into all flours significantly elevated the peak viscosity by about 0.9-2.6 folds when compared to non-MG samples. Hot paste viscosity, breakdown and final viscosity for all flour mixtures significantly increased with increasing of MG which ranged from 81-427, 37-559 and 152-463 RVU, respectively. Freeze-thaw stability measurement demonstrated that higher level of MG in wheat and rice gel mixtures could decrease syneresis. However, MG had no effect on syneresis of waxy rice gel. Presence of MG in flours alters the pasting properties and syneresis effect. It is suggested that higher viscosity and lower syneresis of gels could be modified by MG.
文摘Many persons worldwide are deficient in micronutrients, two of the most common being vitamin A and iron. Fortification of staple food is a commonly used and effective method of boosting micronutrient intake. Wheat flour is widely used around the world and makes a good vehicle for fortification, but there is a lack of studies on the storage stability of fortified wheat flour. In this study, we fortified wheat flour with elevated levels of vitamin A and three sources of iron and stored it for up to 16 weeks at refrigerated or room temperature or elevated temperature. The rate of disappearance of vitamin A was monitored by high pressure liquid chromatography, and the rate of disappearance was fotmd to be directly proportional to the duration of storage and storage temperature. Higher temperatures contributed to greater loss of vitamin A. Iron, regardless of source, did not play a major role in contributing to the rate of vitamin A loss. Flour functionality was assessed by baking loaves of bread from the stored flour and assessing physical properties as well as subjecting the loaves to an expert sensory panel. Functionality also changed with time and temperature of storage, but sensory analysis found that these changes were not detrimental to the quality of bread baked from the stored flours. Trained sensory panelists found that breads baked from flours fortified with ferrous sulfate and stored at the three temperatures for times up to eight weeks were markedly different from fortified flours using hydrogen reduced irons.
文摘The objective of this research is to investigate the impact of infestation by the confused flour beetle Tribolium confusum on the specification of flour and its product. The results of this work showed that infestation by the confused flour beetle with 5 pairs of adult stage and its progeny within 3 months period may cause high deterioration and damaged of the flour specification. The people in lraq get their flour from some official and non-official mills which they produce not so good quality of this flour in addition to which it contains some times an infestation with the two species of the flour beetles T. castaneum and T. confusum, when people do not use this quantity as quickly as possible during this period of storage, the beetles will be increased in numbers and make the flour unacceptable for any kind of pastes or bread. The infestation by this beetle causes great pollution to the flour by the ecdysial of larvae and a bad smell that it leaves on the flour and all its products.
文摘Samples of 12 hard winter wheats and their flours that produced breads varying in crumb grain scores were studied for 38 quality parameters including: wheat physical and chemical characteristics; flour ash and protein contents,starch damage,swelling power,pasting characteristics,and flour particle size distribution; dough properties determined by a mixograph; and breadmaking properties for pup loaves (100g flour). Only two parameters,the protein content of wheat and the granulation of flour,showed significant correlations with bread crumb grain scores. Protein content of wheat ranging 12.9%~14.5% determined by an NIR method showed a weak inverse relationship (r =-0.61,p<0.05) with bread crumb grain score. Flour particle size distribution measured by both Alpine Air Jet Sieve and NIR methods revealed that the weight wt % of particles less than 38μm in size and representing 9.6%~19.3% of the flour weights was correlated positively (r =0 .78,p<0.01) with crumb grain score,whereas wt % of flour particles larger than 125μm had an inverse relationship (r =-0.60,p<0.05) with crumb grain score.
基金The research was performed under project“New Food”of the NAZV,Czech Republic,No.321 51 15 10.
文摘Wheat/hemp and wheat/teff model composites were prepared as 90:10 and 80:20 w/w blends, using two different Czech commercial wheat flour samples (standards M, M1) and bright/dark forms of these non-traditional crops flour. The objective of this study was to determine the effect of alternative flour samples on the blend compositional profiles including dietary fibre content, on the technological quality described by modern Solvent Retention Capacity method and on laboratory baking test results. According to seeds composition, nutritional flour enrichment reached higher levels of protein (from approx. 13.0% about 30% vs. 6%) and fibre contents (from approx. 3.3% about 50% vs. 30%) in the case of hemp and teff samples. In terms of the SRC profile, the qualitatively better sample M was weakened by hemp flour additions, while somewhat worse sample M1 was improved by teff flour additions. Results from the baking test showed that the hemp composites were partly dependent on hemp flour form. Volumes of bread with bright hemp were diminished from 257 mL/100g up to 196 mL/100g, the products containing dark hemp increased up to 328 mL/100g. Teff-fortified bun volumes were evaluated in close range of 325 - 369 mL/100g against 381 mL/100g for standard M1. Sensorial score of wheat/hemp breads were worse owing to spicy taste and fatty aftertaste, while hay-like by-taste in wheat/teff bread could be tolerable of 10% in recipe.