White Wheat Flour Research Articles

Including Indigestible Carbohydrates in the Evening Meal of Healthy Subjects Improves Glucose Tolerance, Lowers Inflammatory Markers, and Increases Satiety after a Subsequent Standardized Breakfast

Low-glycemic index (GI) foods and foods rich in whole grain are associated with reduced risk of type 2 diabetes and cardiovascular disease. We studied the effect of cereal-based bread evening meals (50 g available starch), varying in GI and content of indigestible carbohydrates, on glucose tolerance and related variables after a subsequent standardized breakfast in healthy subjects (n = 15). At breakfast, blood was sampled for 3 h for analysis of blood glucose, serum insulin, serum FFA, serum triacylglycerides, plasma glucagon, plasma gastric-inhibitory peptide, plasma glucagon-like peptide-1 (GLP-1), serum interleukin (IL)-6, serum IL-8, and plasma adiponectin. Satiety was subjectively rated after breakfast and the gastric emptying rate (GER) was determined using paracetamol as a marker. Breath hydrogen was measured as an indicator of colonic fermentation. Evening meals with barley kernel based bread (ordinary, high-amylose- or β-glucan-rich genotypes) or an evening meal with white wheat flour bread (WWB) enriched with a mixture of barley fiber and resistant starch improved glucose tolerance at the subsequent breakfast compared with unsupplemented WWB (P < 0.05). At breakfast, the glucose response was inversely correlated with colonic fermentation (r = −0.25; P < 0.05) and GLP-1 (r = −0.26; P < 0.05) and positively correlated with FFA (r = 0.37; P < 0.001). IL-6 was lower (P < 0.01) and adiponectin was higher (P < 0.05) at breakfast following an evening meal with barley-kernel bread compared with WWB. Breath hydrogen correlated positively with satiety (r = 0.27; P < 0.01) and inversely with GER (r = −0.23; P < 0.05). In conclusion, the composition of indigestible carbohydrates of the evening meal may affect glycemic excursions and related metabolic risk variables at breakfast through a mechanism involving colonic fermentation. The results provide evidence for a link between gut microbial metabolism and key factors associated with insulin resistance.

Effects of Added Minerals on Pasting of Partial Waxy Wheat Flour and Starch and on Noodle Making Properties

ABSTRACTMineral content, as determined and expressed by ash content, serves as an index of wheat flour quality for flour millers and food manufacturers who prefer flour of low mineral content, even though the significance of mineral content on the functional properties of wheat flour is not well understood. We explored whether minerals have any influence on the functional properties of wheat flour and product quality of white salted noodles. Ash, obtained by incinerating wheat bran, was incorporated into two hard white spring wheat flours and their starches to raise the total ash content to 1, 1.5, or 2%. Pasting properties were determined using a rapid visco analyzer (RVA). Addition of ash increased the peak viscosity of the flours in both water and buffer solution but did not affect the peak viscosity of starch. Wheat flours with added ash showed lower pasting temperature by approximately 10°C in buffer solution. Mineral extracts (15.3% ash) isolated from wheat bran, when added to increase the ash content of wheat flour and starch to 2%, increased the peak viscosity and lowered the pasting temperature of flour by 13.2–16.3% but did not affect the pasting properties of the isolated starch. The mineral premix also increased peak viscosity of wheat flour but not in starch. Added ash increased noodle thickness and lowered water retention of cooked noodles while it exhibited no significant effect on cooked noodle texture as determined using a texture analyzer.

Relationships of High Molecular Weight Glutenin Subunit Composition and Molecular Weight Distribution of Wheat Flour Protein with Water Absorption and Color Characteristics of Noodle Dough

ABSTRACTColors of noodle doughs made from hard white winter wheat flours from Oregon were measured at optimum noodle water absorptions (NWA). Partial correlations, removing effect of protein concentration, indicated that NWA had negative relationships with 0 hr L* and 24 hr b*, and positive relationships with 0 and 24 hr a*. Kernel hardness index had positive simple and partial correlations with NWA without any significant (P &lt; 0.05) correlation with color parameters. High molecular weight glutentin subunits (HMW‐GS) significantly (P &lt; 0.05) affected all measured noodle parameters except for 0 hr L*. Covariance analysis, using protein concentration as a covariate, indicated that HMW‐GS significantly affected NWA and a* (P &lt; 0.01). Wheat cultivars with HMW‐GS 17+18 showed significantly higher mean NWA and a* values than those with alternative Glu‐B1 subunits. Protein molecular weight distributions affected noodles, as shown by significant correlations with absorbance areas and % areas of protein size exclusion (SE) HPLC chromatograms. Protein fractions that had positive correlations with redness had negative correlations with yellowness. Applying multivariate analyses to SE‐HPLC data to derive calibration models to predict fresh noodle dough a* and b* values had R2 &gt; 0.91 and cross validations values of R2 &gt; 0.75.

Characterisation of flour, starch and fibre obtained from sweet potato (kumara) tubers, and their utilisation in biscuit production

SummarySweet potato (kumara) tubers of differing colours (orange, red and white) were used to produce tuber flour, a purified starch fraction and an isolated fibre extract. The fractions from each tuber colour were added into a biscuit mixture, and the effects of tuber source and fraction composition were observed in relation to the physico‐chemical characteristics of biscuits. Addition of sweet potato flour and fibre fractions to white wheat flour significantly reduced the pasting properties (peak and final viscosity) of the resulting gels by up to seven‐fold compared with the control wheat flour gel (as determined by the Rapid Visco Analyser). The addition of sweet potato starch affected the pasting properties of wheat flour–sweet potato starch mixes to a lesser extent. Biscuit texture (force required to cause a biscuit to fracture) was significantly reduced with the incorporation of sweet potato fibre into the biscuit dough preparation, this was linked to a reduction in biscuit thickness and spread ratio. However, the addition of sweet potato flour and starch resulted in biscuits of similar firmness as the control biscuits.

Dough properties and breadmaking qualities of whole waxy wheat flour and effects of additional enzymes

AbstractBACKGROUND: Waxy wheat, a new kind of genetically back‐crossed wheat, was applied to make whole bread in this study. Dough properties and bread quality of the whole waxy wheat flour, which was milled from 100% whole grains containing bran and germ, were determined.RESULTS: Whole waxy wheat had lower protein and lipid contents but higher dietary fiber content than whole regular wheat flour. Pasting temperature and viscosity of the whole waxy wheat flour were significantly lower than those of the whole regular wheat. However, the white wheat flour milled from wheat grains with 48% recovery had significantly higher peak viscosity than the whole waxy wheat. Bread made from the whole waxy wheat flour was significantly softer than that from the whole regular wheat flour during storage. However, bread made from whole waxy wheat had significantly lower specific volume than that from the white waxy flour because of the high amount of dietary fiber. Addition of cellulase increased paste viscosity, lowered dough mixing properties and reduced the firmness of the bread. The addition of pentosanase also increased paste viscosity, lowered dough mixing properties, improved loaf volume of bread but increased the firmness of breadcrumbs, while the addition of α‐amylase only increased final viscosity of flour and did not affect dough properties and bread qualities of whole waxy wheat flour.CONCLUSION: As a result, waxy wheat shows superior properties for making whole breads. Additional enzymes are also necessary to improve bread quality and nutritive values of whole waxy bread. Copyright © 2007 Society of Chemical Industry

White Whole Wheat Flour is an Acceptable Substitute for All-Purpose Flour in Shortbread Cookies

White Whole Wheat Flour is an Acceptable Substitute for All-Purpose Flour in Shortbread Cookies

Effect of Flour Extraction Rate on White and Red Winter Wheat Flour Compositions and Tortilla Texture

ABSTRACTWheat flours commercially produced at 74, 80, and 100% extraction rates made from hard white winter wheat (WWF) and hard red winter wheat (WRF) were used to produce tortillas at a commercial‐scale level. Flour characteristics for moisture, dry gluten, protein, ash, sedimentation volume, falling number, starch damage, and particle‐size distribution were obtained. Farinograms and alveograms were also obtained for flour‐water dough. A typical northern Mexican formula was used in the laboratory to test the tortilla‐making properties of the flours. Then commercial‐scale tortilla‐baking trials were run on each flour. The baked tortillas were stored at room and refrigeration temperatures for 0, 1, 2, and 3 days. Maximum stress and rollability were measured every day. Tortilla moisture, color, diameter, weight, and thickness were measured for each treatment. Finally, tortilla acceptability was tested by an untrained sensory panel. Analyses of variance (ANOVA) were performed on the data. WWF had higher protein content, dry gluten, sedimentation volume, and water absorption than the WRF. The WWF was the strongest flour based on farinograph development time and alveograph deformation work. It also produced the most extensible dough measured with the alveograph (P/L). Flour protein and ash contents, water absorption, and tenacity increased directly with the flour extraction rate. Both WWF and WRF performed well in commercial‐scale baking trials of tortillas. Tortillas made with both types of flours at 74 and 80% extraction rates had the best firmness and rollability. However, tortillas made with WWF 80% had the best color (highest L value). Tortillas prepared with 100% extraction rate flour were also well accepted by the sensory panel, had good textural characteristics, and became only slightly firm and slightly less rollable after three days of storage at room temperature.

Comparison of proximate, mineral and vitamin composition of common Brazilian and US foods

Because food analysis is costly and laborious, analytical data are frequently borrowed from tables of developed countries and incorporated in tables of developing countries. Taking advantage of the new Brazilian table of food composition, which is based on representative national sampling and actual analyses, an attempt is made to gain an insight into the adequacy of this practice by comparing data from the Brazilian and US tables in terms of the proximate, mineral and vitamin composition of 19 selected foods, common to both countries. For proximate composition, data agreement is excellent for dry whole milk; good for condensed milk, dry nonfat instant milk and canned peas; and fairly good for black beans, milk chocolate, lentils, oats, long-grain white rice and wheat flour. Greater variation is seen with minerals and vitamins. In terms of minerals, agreement is very good only for dry whole milk, good for black beans and canned peas; fairly good with milk chocolate, lentils, wheat flour and natural yogurt. For vitamins, agreement can be considered good only for wheat crackers and yogurt and fairly good for condensed milk and dry whole milk. The comparison indicates that data may be borrowed for proximate composition provided the foods are equivalent. However, caution must be taken in borrowing data for micronutrients.

Effects of meals with high soluble fibre, high amylose barley variant on glucose, insulin, satiety and thermic effect of food in healthy lean women

To examine the effect of barley flour (barley cultivar, Hordeum Vulgare var Himalaya 292) incorporated into breakfast and lunch compared with otherwise identical meals containing white wheat flour on the thermic effect of food (TEF), subsequent food intake and metabolic parameters. Randomized single blinded crossover study. Outpatient setting. Fourteen healthy women consumed a test breakfast at 0700 h. Energy expenditure, respiratory quotient (RQ), appetite ratings using a visual analogue scale (VAS), insulin and glucose levels were measured before and after a test lunch at 1330 h. Food intake was recorded for the remainder of the day. The TEF was 5% for both test lunches and meal type did not affect any variable measured by the VAS. There was an increase in post-prandial RQ above baseline (0.80) independent of treatment (0.88 and 0.90 for barley and wheat-containing meals, respectively, P<0.001). Mean area under the glycaemic response curve (AUC) for wheat-containing meals was 4.68+/-1.67 mmol/l/h, 22% higher than for the barley-containing meals (3.67+/-1.91 mmol/l/h), P=0.05. AUC of insulin in response to wheat-containing meals (78.1+/-35.3 mIU/l/h) was 32% greater than barley-containing meals (52.8+/-24.7 mU/l/h), P<0.02. Ad libitum food intake over the next 10 h was reduced by 23% (9.6 vs 11.0 MJ, P<0.05) after the wheat-containing meals compared to the barley-containing glycaemic index meals. Inclusion of an ingredient containing increased soluble fibre and amylose did not reduce spontaneous food intake but rather was associated with higher subsequent energy intakes despite its reduced glycaemic and insulinemic effects. CSIRO, Human Nutrition, Adelaide, Australia.

Impact of α‐Amylases on Quality Characteristics of Asian White Salted Noodles Made From Australian White Wheat Flour

ABSTRACTThe consumer acceptance of white salted Asian noodles depends on starch characteristics, and the purpose of this study has been to investigate the potential of exogenous α‐amylases to enhance textural characteristics of this product. Noodles were prepared from commercial flours with low α‐amylase activity, and the endogenous enzyme remained relatively stable during various processing and storage treatments. α‐Amylase preparations of bacterial origin and from barley malt were incorporated, and the products were assessed by texture analysis and electron microscopy, as well as for color characteristics. On addition of the amylase preparations, noodles were softer when texture was assessed using either a flat cylinder probe or an axial blade. Some discoloration occurred in treated noodle sheets, although this was minimal in final products that had been cooked immediately after preparation or following drying. Scanning electron microscopy confirmed that the α‐amylase of bacterial origin had greater impact upon starch than that from barley malt. The results have implications for understanding of the adverse impact of preharvest sprouting on product characteristics. The results show that softer noodles have been obtained at these levels of enzyme additions. This was true for both enzyme preparations used. Differences in hardness (as measured using the flat cylinder probe) were greater than those for firmness (as measured using the axial blade).

Measurement of lipoxygenase in Australian white wheat flour: the effect of lipoxygenase on the quality properties of white salted noodles

AbstractThe enzyme lipoxygenase has a number of functions in breadmaking. Although white salted noodles are a staple food in various countries, the significance and potential of lipoxygenase in noodlemaking are less well understood. In these products a bright, uniform appearance is particularly important and so the aim of the present research has been to study the effect of endogenous and exogenous lipoxygenase upon discolouration of white salted noodles as well as on the textural and structural attributes. Similar lipoxygenase levels were recorded in the flours studied and no significant losses of activity were found during noodle manufacture and subsequent storage. Less discolouration occurred in treated noodle sheets compared with control samples. Discolouration happened to a lesser extent when samples were cooked immediately after preparation or drying for both treated and control noodles. Whiter noodle sheets were obtained when a soybean lipoxygenase was added to the formulation. Textural and structural properties of white salted noodles were not adversely affected by enzyme addition, giving firm, elastic and non‐sticky products. It is concluded that the incorporation of the lipoxygenase preparation offers prospects for colour enhancement of white salted noodles. Copyright © 2006 Society of Chemical Industry

Effects of cell wall components on the functionality of wheat gluten

Normal white wheat flours and especially whole meal flour contain solids from the inner endosperm cell walls, from germ, aleurone layer and the outer layers of cereal grains. These solids can prevent either gluten formation or gas cell structure. The addition of small amounts of pericarp layers (1–2%) to wheat flour had a marked detrimental effect on loaf volume. Microstructural studies indicated that in particular the epicarp hairs appeared to disturb the gas cell structure. The detrimental effects of insoluble cell walls can be prevented by using endoxylanases. It has been shown that some oxidative enzymes, naturally present in flour or added to the dough, will oxidise water-extractable arabinoxylans via ferulic acid bridges, and the resulting arabinoxylan gel will hinder gluten formation. The negative effects of water-unextractable arabinoxylans on gluten yield and rheological properties can be compensated by the addition of ferulic acid. Free ferulic acid can probably prevent arabinoxylan cross-linking via ferulic acid.

QUALITY ATTRIBUTES OF CANADIAN HARD WHITE SPRING WHEAT

ABSTRACT Quality characteristics of five pilot‐scale milled Canadian hard white spring wheats were compared to a No.1 grade commercial composite Canada Western Red Spring (1CWRS) wheat. One metric ton of samples was milled on the Canadian International Grains Institute pilot Buhler mill (Buhler AG, Uzwil, Switzerland) into straight‐grade (SG), 85% and whole wheat flours. At the SG extraction level, the white wheats with their lighter colored seed coats had improved milling yields (up to 2.6%) and lower ash (0.01–0.09%) than the 1CWRS control wheat. Majority of white wheat flours had higher protein contents than the 1CWRS control flours for all flour extractions. Based on dough rheological properties of the flours, three of the white wheats (Kanata, Snowbird and BW 275 ) were equal to or better than the red 1CWRS control for nearly all farinograph and mixograph parameters at all flour extractions other than farinograph absorption. Two of the white wheat lines (RL 4863 and RL 4858 ) had excessively weak and overly strong dough properties, respectively. Evaluation of pan bread, bagels and tortillas showed that white wheats generally produced end‐products that were comparable or superior to 1CWRS and that their most significantly positive quality compared to 1CWRS was their substantially lighter colored end‐products.

Dietary calcium and health

Dietary calcium and health

Determination of Zinc Contents in Iranian Flat Breads

Zinc is an essential element for the maintenance of good health. It is necessary for the activity of several enzymes involved in energy changes and protein formation. Bread is one of the foods that have some zinc. Bread and other cereal products provide the most of calories and protein intakes of Iranian people in cities. Iranian flat breads such as lavash, taftoon, barbari and sangak generally are produced from soft white wheat flours of higher extraction levels compared to western type breads. The diet of Iranian people is more bread and other cereal products provide as much as 50-90 % of total caloric. For zinc monitoring in flat breads, 36 flat bread samples were collected from bakeries in Tehran city in 2004 and analyzed by flame atomic absorption spectrophotometry for zinc metal. The mean and standard deviation of zinc content in lavash, barbari, taftoon and sangak breads were 12.17±1.91, 10.75±2.64, 10.41±3.54 and 14.25±3.56 mg/kg, respectively. Estimated intake of zinc based on consumption of Iranian flat breads is 3.499 mg per person per day. Flat breads are good sources of zinc and they can supply some of zinc requirements of human body for preventing of zinc deficiency.

Wet-Milling of Flours from Red, White and Low-Polyphenol Oxidase White Wheats

Straight-grade and high-yield flours milled from red, white and low-polyphenol oxidase (PPO) activity white wheats were wet-milled to give gluten, starch, tailings and water-soluble fractions. Wet gluten fractions were either oven-dried or freeze-dried and ground to obtain dry gluten. White wheats yielded slightly more flour with higher lightness ( L*) than the red wheat. The wet-milling properties of all flours were comparable. The wet and oven-dried gluten fractions isolated from the low-PPO flours were the lightest, followed by the gluten fractions from the white and red wheat flours. The L* of the oven-dried gluten fractions from the low-PPO flours were ~ 1-3% higher than those from the white and red wheat flours. As the flour yield increased, the L* of the dry gluten fractions from all flours decreased likewise. However, the high-yield low-PPO white wheat flour gave the dry gluten with almost equal L* to the gluten isolated from the straight-grade red wheat flour, indicating the potential of the low-PPO white wheat flour in manufacturing brighter gluten.

Hard White Wheat and Gold Medal Flour: General Mills' Contracting Program*

General Mills produces Gold Medal Flour, the largest branded flour product in the United States. General Mills wants to switch from using hard red wheat to hard white wheat to produce Gold Medal Flour. Hard white wheat is not widely produced in the United States. To ensure a stable supply, General Mills is creating an extensive contracting program in the northern and central Great Plains. The objective of this case is for students to understand alternative methods for procuring wheat and the importance of wheat variety functionality.

Alkylresorcinols as Markers of Whole Grain Wheat and Rye in Cereal Products

The alkylresorcinol (AR) content of Swedish wheat grain samples, as well as of cereal ingredients and cereal foods containing wheat and rye, was determined. The average total AR content in Swedish wheat was 412 microg/g (ranging between 227 and 639 microg/g), which is lower than that in Swedish rye analyzed in a previous study. The relative composition of AR homologues was consistent for wheat samples and differed markedly from that of rye. Notably, the ratio of the homologues C17:0/C21:0 was approximately 0.1 in wheat and approximately 1.0 in rye, indicating that it can be used to distinguish between those two cereals. The AR content in cereal foods commonly consumed in Sweden varied widely, from nondetectable levels in white wheat flour and products not containing the outer parts of wheat and/or rye to >900 microg/g in some whole grain rye products. AR content in cereal foods was calculated from their recipes using average AR values for the cereal ingredients determined in this study. As there was a good correlation between calculated and analyzed AR levels in cereal foods (R2 = 0.91), it is possible to estimate the proportion of whole grain wheat and/or rye in a given cereal product on the basis of AR content and C17:0/C21:0 ratio. ARs appear to be good markers of whole grain wheat and rye in foods, and their analysis may be an objective way to identify foods rich in whole grain wheat and/or rye or brans thereof.

Effects of Secondary Structures of Heated Egg White Protein on the Binding Between Prime Starch and Tailings Fractions in Fresh Wheat Flour

ABSTRACTDried egg white protein was heated at 120°C for 1 hr, added to a fresh wheat flour (protein 8.6%), and the protein and wheat flour were subjected to acetic acid (pH 3.5) fractionation. The results showed that egg white protein increased the binding between prime starch (PS) and tailings (T) fractions in wheat flour. Several conditions for heating of egg white protein were examined to determine 1) the effect of the amount of water added to the protein before heating; 2) the effect of heating time (hr) on protein at 120°C; and 3) the effect of heating temperature on the binding between PS and T fractions. The amount of protein per 50.0 g of wheat flour was further examined for the maximum binding between PS and T fractions. The heated egg white protein was analyzed by Fourier transform infrared (FT‐IR) spectroscopy, and the changes in the secondary structures (α‐helix, β‐sheets, and others) of the protein caused by heating were studied. When egg white protein was heated at 120°C for 8 hr, 9.0% of the α‐helix structures of egg white protein decreased to 3.0%, and 37.0% of the β‐sheet structures increased to 41.0%. The decrease of α‐helix and increase of β‐sheet structures of heated egg white protein were related to the increase in the binding between PS and T fractions in the same heated egg white protein and wheat flour sample. A relationship between the structural changes in heated egg white protein (180°C, 1 hr) and the binding between PS and T fractions in the heated egg white protein and wheat flour was also observed.

Study of selenium species distribution in biological tissues by size exclusion and ion exchange chromatagraphy inductively coupled plasma–mass spectrometry

Selenium species present in water-soluble fractions of proteins of lyophilised biological samples, such as fish (tuna and trout), shellfish (krill, oyster and mussel), vegetal tissues (white clover and wheat flour) and selenized yeast were evaluated. The water-soluble fractions with and without 4% (w/v) sodium dodecyl sulphate were analysed by size exclusion chromatography coupled to both inductively coupled plasma–mass spectrometry (SEC–ICP–MS) and UV spectrophotometers. Two different columns with effective separation ranges between 300 and 1 kDa (Biosep-SEC-2000) and 7 and 0.1 kDa (Superdex Peptide HR 10/30) were used, with 5 mM sodium phosphate at pH 7.2 (0.8 ml min −1) and 5 mM sodium phosphate with 60 mM NaCl at pH 7.5 (0.6 ml min −1) as mobile phases, respectively. The enzymatic digests of both the water-soluble fractions and the non-soluble residues were analysed by cation exchange chromatography–ICP–MS, using a Hamilton PRP-X200 column and 4 mM pyridine (1 ml min −1) at pH 2.8 and 4.7 as mobile phases. The presence of high molecular weight selenoproteins (150–50 kDa) in the samples studied, except for fish and white clover with proteins <30 kDa, was demonstrated and low molecular weight (<5 kDa) compounds were also found. Selenomethionine species (SeMet) within the range of 0.2–600 μg g −1 was quantified in the selected tissues, although selenocystine (SeCys 2) was identified only in vegetal samples (0.1–0.7 μg g −1). Trimethylselenonium ion was quantified (0.1–0.3 μg g −1) in oyster, mussel, trout and white clover tissues. Inorganic selenium as selenite was found in the selenized yeast, krill, and white clover samples (0.2–3 μg g −1), while selenate was found to be present only in yeast tissues (8 μg g −1).