共查询到20条相似文献，搜索用时 359 毫秒
1.
Juliano Luiz De Almeida Bram Pareyt Lien R. Gerits Jan A. Delcour 《Cereal Chemistry》2014,91(4):321-326
During whole grain flour (WGF) storage, lipase activity causes partial loss of its functionality and the sensory acceptability of products produced from it. The objective of this research was to evaluate the effect of steaming and washing on lipase activity in (fractions of) wheat. Steam treatment conditions were optimized for wheat grains and their bran, shorts, and flour fractions. Lipase activities were determined colorimetrically, as were peroxidase, endoxylanase, and α‐amylase activities. Steaming grains for 180 s effectively inactivated lipase, peroxidase, endoxylanase, and part of the α‐amylase without gelatinizing starch. The work further demonstrated that lipase is mainly, if not only, located in the bran fraction. Separate bran treatment holds promise for obtaining WGF with reduced lipase activity but without altered functional properties. Washing grains did not reduce WGF lipase activity. 相似文献
2.
《Cereal Chemistry》2017,94(6):956-962
The effects of the β‐glucan content and pearling of barley on abdominal obesity and the proinflammatory state were investigated in diet‐induced obese mice. Male C57BL/6J mice were randomly divided into four groups and fed either a high‐fat diet containing high‐β‐glucan barley (Beau Fiber [BF]) or a high‐fat diet containing β‐glucan‐free barley (Shikoku‐hadaka 84(bgl ) [BGL]) as whole grain flour or 60% pearled flour for 12 weeks. The weights of mesenteric fat, serum total and low density lipoprotein cholesterol levels, serum insulin and fasting glucose levels, oral glucose tolerance test results, and messenger RNA (mRNA) expression of proinflammatory markers in epididymal fat in both BF groups were significantly lower than those of both BGL groups. The abundance of Bacteroides in both BF groups was significantly higher than that in both BGL groups, whereas the abundance of Clostridium clusters in both BF groups was significantly lower than that in both BGL groups. No significant differences between the whole grain and pearled flours were observed. These results suggest that high‐β‐glucan barley attenuates the progression of abdominal obesity and the proinflammatory state in diet‐induced obese mice compared with β‐glucan‐free barley, possibly by modifying insulin secretion and the microbiota. 相似文献
3.
《Cereal Chemistry》2017,94(3):502-507
Previously, we showed that tempering with saline organic acid solutions can reduce the aerobic plate count of wheat by as much as 4.3 log CFU/g. The purpose of this study was to evaluate the impact of these tempering solutions on the functional properties of resulting whole grain (WGF) and straight‐grade (SGF) flours. Wheat was tempered to 15.5% moisture by tempering with sterile distilled water (control) or solutions containing NaCl (26% [w/v]) together with organic acid (acetic or lactic 2.5 and 5.0% [v/v]). After milling, fractions were collected and recombined as needed to obtain WGF or SGF. The acid content in WGF was higher than in SGF, indicating limited penetration of the organic acids into the endosperm of the grain. In WGF, the saline organic acid treatments caused a decrease in paste viscosity and bread crumb cell sizes in breads. In SGF, the saline organic acid treatments caused significant changes in paste viscosity and some Mixograph parameters; however, principal components analysis indicated that the treatments did not substantially affect SGF functionality. Thus, WGF was altered by the saline organic acid solutions, whereas SGF functionality was minimally affected by tempering treatments, perhaps because of acids only partially penetrating into the endosperm. 相似文献
4.
In this study, effects of increasing levels of wheat bran and barley flour on dough properties and bazlama quality were investigated. Bazlama is a flat bread commonly consumed in Turkey. Flours of wheat cultivars Gün and Gerek, flour of barley cultivar Tokak, and Gerek bran mixture were used. Part of the wheat flours were replaced with barley flour at 10, 20, 30, and 40% levels and Gerek bran mixture at 5, 10, 15, and 20% levels. Farinogram properties of mixtures were determined. Bazlama samples were subjected to sensory analysis for external appearance, shape and symmetry, crust color, crumb color and structure, mouthfeel, taste and aroma. Increasing levels of bran and barley flour caused decreases in all sensory properties. The deteriorative effect of barley flour on bazlama properties was generally more obvious when compared to bran supplementation. However, all bazlama samples were considered acceptable. Penetrometer values of bazlama samples showed that increasing levels of barley flour created significantly softer bazlama. However, in bran-supplemented bazlama samples, effect of bran on softness was found to be insignificant in both cultivars. Bazlama samples supplemented with bran had lower L values and higher a and b values for color when compared to those supplemented with barley flour. In all samples, effect of increasing levels of barley flour on residual β-glucan was found to be insignificant in both cultivars. Acid detergent fiber and neutral detergent fiber values increased with increasing levels of bran, and the changes in both cultivars were similar. 相似文献
5.
Whole grain wheat products are a growing portion of the foods marketed in North America, yet few standard methods exist to evaluate whole grain wheat flour. This study evaluated two flour milling systems to produce whole grain soft wheat flour for a wire‐cut cookie, a standard soft wheat product. A short‐flow experimental milling system combined with bran grinding in a Quadro Comil produced a whole grain soft wheat flour that made larger diameter wire‐cut cookies than whole grain flour from a long‐flow experimental milling system. Average cookie diameter of samples milled on the short‐flow mill was greater than samples milled on the long‐flow system by 1 cm/two cookies (standard error 0.09 cm). The long‐flow milling system resulted in more starch damage in the flour milling than did the short‐flow system. The short‐flow milling system produced flours that were useful for discriminating among wheat cultivars and is an accessible tool for evaluating whole grain soft wheat quality. 相似文献
6.
This study was designed to compare the glucose, insulin, and glucagon responses to consumption of high‐soluble β‐glucan compounds from oats and barley. After an initial medical evaluation that included blood and urine testing, 11 men and 11 women, nondiabetics, 35–57 years, were selected. Subjects consumed a controlled diet for three days. On the third day of five successive periods, subjects consumed 1 g/kg of body weight of carbohydrate as glucose or 0.66 g/kg of body weight pudding (predominantly sucrose) and 0.33 g/kg of body weight as oat bran, barley flour, oat or barley extract (Nu‐trimX) in a Latin square design. Order of treatment was randomly assigned. Glycemic responses were calculated using the trapezoid method. Data were analyzed using mixed procedure analysis of variance program. Glucose responses to oats, barley, and both extracts, and areas under the curve were significantly lower than responses to the glucose solution (P < 0.0001). Insulin responses for the barley extract were lowest and were significantly lower than for glucose solution. Oat and barley extracts retain the beneficial effects of the grains from which they are extracted. High‐soluble fiber barley is more effective than standard oats. Oat and barley carbohydrate‐based fat substitutes can provide a useful addition to menus to control plasma glucose responses. 相似文献
7.
Joanne Slavin 《Cereal Chemistry》2010,87(4):292-296
Whole grains contain all parts of the grain: the endosperm, germ, and bran. Whole grains are rich in fermentable carbohydrates that reach the gut: dietary fiber, resistant starch, and oligosaccharides. Most research that supports the importance of grains to gut health was conducted with isolated fiber fractions, rather than whole grains. Whole grains are an important source of dietary fiber and grain fibers such as wheat, oats, barley, and rye increase stool weight, speed intestinal transit, get fermented to short chain fatty acids, and modify the gut microflora. Wheat bran is particularly effective in increasing stool weight; wheat bran increases stool weight by a ratio of 5:1. In contrast, many novel fibers that are easily incorporated into beverages and foods increase stool weight only on a ratio of 1:1. In vitro fermentation studies with whole grains have been published. Carbohydrates of oat bran (rich in β‐glucan) were consumed by bacteria faster than those of rye and wheat brans (rich in arabinoxylan). Grain fibers were fermented more slowly than inulin, causing less gas production. Wheat is particularly high in fructo‐oligosaccharides, while wheat germ is high in raffinose oligosaccharides. Some in vivo studies show the prebiotic potential of whole grains. Whole grain breakfast cereal was more effective than wheat bran breakfast cereal as a prebiotic, increasing fecal bifidobacteria and lactobacilli in human subjects. Wheat bran consumption increased stool frequency. Thus, the gut enhancing effects of cereal fibers are well known. Limited data exist that whole grains alter gut health. 相似文献
8.
Dark discoloration negatively influences the aesthetic properties of barley‐based food products. The effects of abrasion and heat treatment of grains, exclusion of oxygen, and the use of antibrowning agents on the retardation of darkening in barley flour gel or dough were determined in four types of barley, including hulled proanthocyanidin‐containing and hulled proanthocyanidin‐free, hulless regular, and hulless waxy barley. Abrasion by >30% in hulled barley and by >15% in hulless barley significantly increased the brightness (L*) of barley flour dough by 0.1–7.1. Steam heating of abraded grains also significantly increased the L* of barley flour gels by 1.8–3.4. Ascorbic acid at 1,500 ppm was most effective for retarding discoloration of barley flour dough, followed by 50 ppm of 4‐hexylresorcinol, which is an enzyme competitive inhibitor. The discoloration of barley flour dough was also effectively reduced by storing the dough sheets at 4°C under nitrogen gas to exclude oxygen or under anaerobic conditions at 20°C. Discoloration of barley‐based food products may be effectively controlled by selecting genotypes with low discoloration development such as proanthocyanidin‐free genotypes, by lowering total polyphenol content or polyphenol oxidase (PPO) activity through abrasion, by heat treatment, by exclusion of oxygen, and by the use of enzyme inhibitors. 相似文献
9.
One nonwaxy (covered) and two waxy (hull-less) barleys, whole grain and commercially abraded, were milled to break flour, reduction flour, and the bran fraction with a roller mill under optimized conditions. The flour yield range was 55.3–61.8% in whole grain and increased by 9–11% by abrasion before milling. Break flours contained the highest starch content (≤85.8%) independent of type of barley and abrasion level. Reduction flours contained less starch, but more protein, ash, free lipids, and total β-glucans than break flours. The bran fraction contained the highest content of ash, free lipids, protein, and total β-glucans but the lowest content of starch. Break flours milled from whole grain contained 82–91% particles <106 μm, and reduction flours contained ≈80% particles <106 μm. Abrasion significantly increased the amount of particles <38 μm in break and reduction flours in both types of barley. Viscosity of hot paste prepared with barley flour or bran at 8% concentration was strongly affected by barley type and abrasion level. In cv. Waxbar, the viscosity in bran fractions increased from 428 to 1,770 BU, and in break flours viscosity increased from 408 to 725 BU due to abrasion. Sugar snap cookies made from nonwaxy barley had larger diameter than cookies prepared from waxy barley. Cookies made from break flours were larger than those made from reduction flours, independent of type of barley. Quick bread baked from nonwaxy barley had a loaf volume similar to that of wheat bread, whereas waxy barley bread had a smaller loaf volume. Replacement of 20% of wheat flour by both waxy and nonwaxy barley flour or bran did not significantly affect the loaf volume but did decrease the hardness of quick bread crumb. 相似文献
10.
Carotenoid value addition of corn whole stillage by red yeast fermentation has yielded astaxanthin‐ and β‐carotene‐enriched distillers dried grains with solubles (DDGS) for animal feed. In this study, commonly used animal feeds (rice bran, wheat bran, milo whole stillage, and soybean products) were subjected to carotenoid value addition. Phaffia rhodozyma and Sporobolomyces roseus monoculture and mixed‐culture submerged fermentation of these substrates supplemented with 5% glycerol were analyzed for astaxanthin, β‐carotene, and residual glycerol. Among all the substrates, full‐fat rice bran and full‐fat soy flour resulted in the highest astaxanthin (80 μg/g by P. rhodozyma) and β‐carotene yields (836 μg/g by S. roseus). P. rhodozyma produced the highest astaxanthin yield on each substrate, whereas depending on the substrate, either the mixed culture or S. roseus monoculture produced the highest β‐carotene yield. Soy hull was a poor substrate for carotenoid value addition. Both yeasts used glycerol as a carbon source for carotenoid production. This study shows that substrates influence the carotenoid yield. However, it is impossible to dissect the effect of specific nutrients on carotenoid production in complex biological substrates. Carotenoid value addition of these substrates provides as much as or more than the required daily dosage of carotenoids in animal feed. 相似文献
11.
The fructan content of Finnish rye grains (13 samples, seven cultivars, harvested in 1998‐2000) varied at 4.6–6.6 g/100 g (db). Commercial whole grain rye flour and rye flakes had fructan content of 4 g/100 g, light refined rye flour had fructan content of 3 g/100 g, and rye bran had fructan content of 7 g/100 g. Fructan content as high as 23 g/100 g was detected in the water‐extractable concentrate of rye bran. Finnish soft rye bread and rye crisp bread contained 2–3 g of fructan/100 g. According to the suggested new definition of dietary fiber, fructans are also classified as dietary fiber. This means that the dietary fiber content of some cereal foods such as rye products may be increased by as much as 20% due to the presence of fructans in the grain. 相似文献
12.
A barley mutant with high‐amylose starch, Himalaya 292, combines the potential cholesterol reducing effects of barley with the gastrointestinal benefits of high‐amylose resistant starches. Himalaya 292 has alterations in the content and composition of a range of grain constituents, thus conditions for successful addition to foods need to be defined. In this study, the rheological and breadmaking properties of doughs prepared by combining wheat flours (with various gluten protein compositions) with various barley genotypes (Himalaya 292 and the control cultivars Himalaya and Torrens) have been determined. The effects of barley addition on the rheological properties of the admixtures differed. While addition of Himalaya 292 increased the strength and reduced the extensibility of admixture doughs, addition of the Himalaya and Torrens barley flours to the wheat flours reduced both strength and extensibility. The addition of Himalaya and Torrens barley flour reduced water absorption levels. However, addition of Himalaya 292 whole grain flour increased the water absorption of the admixtures significantly (P < 0.01). The baking data showed that selection of an appropriate wheat flour with a combination of strength and extensibility allows higher levels of incorporation of barley, facilitating an increased delivery per serving of constituents with positive health attributes in β‐glucan and resistant starch. 相似文献
13.
《Cereal Chemistry》2017,94(6):963-969
Single‐pass and multipass milling systems were evaluated for the quality of whole wheat durum flour (WWF) and the subsequent whole wheat (WW) spaghetti they produced. The multipass system used a roller mill with two purifiers to produce semolina and bran/germ and shorts (bran fraction). The single‐pass system used an ultracentrifugal mill with two configurations (fine grind, 15,000 rpm with 250 μm mill screen aperture; and coarse grind, 12,000 rpm with 1,000 μm mill screen aperture) to direct grind durum wheat grain into WWF or to regrind the bran fraction, which was blended with semolina to produce a reconstituted WWF. Particle size, starch damage, and pasting properties were similar for direct finely ground WWF and multipass reconstituted durum flour/fine bran blend and for direct coarsely ground WWF and multipass reconstituted semolina/coarse bran blend. The semolina/fine bran blend had low starch damage and had desirable pasting properties for pasta cooking. WW spaghetti was better when made with WWF produced using the multipass than single‐pass milling system. Mechanical strength was greatest with spaghetti made from the semolina/fine bran or durum flour/fine bran blends. The semolina/fine bran and semolina/coarse bran blends made spaghetti with high cooked firmness and low cooking loss. 相似文献
14.
Hernot DC Boileau TW Bauer LL Swanson KS Fahey GC 《Journal of agricultural and food chemistry》2008,56(22):10721-10726
Chemical composition and in vitro digestion properties of select whole grains, before and after processing, and their components were measured. Substrates included barley, corn, oat, rice, and wheat. In addition to whole grain flours, processed substrates also were tested as were corn bran, oat bran, wheat bran, and wheat germ. Processing of most substrates resulted in higher dry matter and digestible starch and lower resistant starch concentrations. Dietary fiber fractions varied among substrates with processing. Digestion profiles for most substrates correlated well with their chemical composition. Corn bran and rice substrates were the least fermentable. Extrusion rendered barley, corn, and wheat more hydrolytically digestible and barley and oat more fermentatively digestible. Except for corn bran, all components had greater or equal fermentability compared with their native whole grains. Understanding digestion characteristics of whole grains and their components will allow for more accurate utilization of these ingredients in food systems. 相似文献
15.
《Cereal Chemistry》2017,94(2):333-340
Health claims for barley β‐glucan (BG) have prompted the development of food products containing barley; however, some new products (such as milled grain used without a cook step, as in a smoothie) do not use any form of heat treatment during processing or prior to consumption, which could affect microbial safety and potential health benefits. The aims of this research were to evaluate current commercial barley products for microbial counts and BG characteristics and to determine the effects of different heat treatments on these attributes in whole grain barley samples. Three heat treatments (micronization, roasting, and conditioning) were performed on three cultivars of barley (CDC Rattan, CDC McGwire, and CDC Fibar). The microbial quality was measured with standard plate count (SPC), mold and yeast count (MYC), and coliforms or Escherichia coli . Only four of the 17 commercial barley products tested met acceptable microbial limits used in this study. All three heat treatments applied to the barley samples in this study reduced SPC, MYC, and coliforms to an acceptable level. BG was extracted with an in vitro digestion method to determine its viscosity, molecular weight (MW), and solubility. All three heat treatments produced BG extracts with high viscosity and MW compared with untreated barley. Overall, heat treatments improved both the safety and the potential health benefits from soluble BG in whole grain barley. 相似文献
16.
Cheng Wang Zhigang Tian Lingyun Chen Feral Temelli Hui Liu Yanxin Wang 《Cereal Chemistry》2010,87(6):597-606
This research optimized the extraction of different protein fractions from barley grains and assessed the physicochemical properties of the fractions obtained. Pearling was first used to remove the grain's outer layers (mainly bran and germ) so that the barley cytoplasmic proteins (albumin and globulin) would be enriched in the pearling flour (PF), while endosperm proteins (hordein and glutelin) would be enriched in the pearled grain flour (PGF). Salt, alcohol, and alkaline solutions were then used to extract different barley protein fractions from PF and PGF. The effects of extraction solvent type, pH, temperature, and extraction time on protein content and extraction efficiency were studied. Aqueous ethanol (55%, v/v) efficiently extracted barley hordein from PGF at 60°C, whereas pH 11.5 alkaline solution was the most efficient for extracting both cytoplasmic and endosperm proteins from barley PF and PGF at 23°C. Subunit molecular weight, amino acid composition, and the functional properties of each isolated barley protein fraction were investigated. Barley glutelin demonstrated superior oil‐binding property and emulsifying stability, whereas barley hordein exhibited good foaming capacity. 相似文献
17.
M. S. Izydorczyk J. E. Dexter R. G. Desjardins B. G. Rossnagel S. L. Lagasse D. W. Hatcher 《Cereal Chemistry》2003,80(6):637-644
Roller milling of hull‐less barley generates mill streams with highly variable β‐glucan and arabinoxylan (AX) content. For high β‐glucan cultivars, yields >20% (whole barley basis) of a fiber‐rich fraction (FRF) with β‐glucan contents >15% can be readily obtained with a simple short mill flow. Hull‐less barley cultivars with high β‐glucan content require higher power consumption during roller milling than normal β‐glucan barley. Recovery of flour from high β‐glucan cultivars was greatly expedited by impact passages after grinding, particularly after reduction roll passages. Pearling before roller milling reduces flour yield and FRF yield on a whole unpearled barley basis, but flour brightness is improved and concentration of β‐glucan in fiber‐rich fractions increases. Pearling by‐products are rich in AX. Pearling to 15–20% is the best compromise between flour and FRF yield and flour brightness and pearling by‐products AX content. Increasing conditioning moisture from 12.5 to 14.5% strongly improved flour brightness with only a moderate loss of flour yield on a whole unpearled barley basis. As moisture content was increased to 16.5%, flour yield declined without a compensating improvement in brightness, but the yield of fiber‐rich fraction continued to increase and concentration of β‐glucan in FRF also increased. 相似文献
18.
Buckwheat is a pseudocereal with a strong characteristic aroma. Compounds responsible for the aroma of buckwheat groats were recently identified, but the distribution of aromatic compounds between different fractions of the buckwheat kernel (flour, bran, and husk) is not yet known. In this study, the composition of aromatic compounds in buckwheat seed fractions was investigated and compared to the composition of aromatic compounds in groats produced from the same batch of buckwheat seeds. Volatiles from each sample were extracted with simultaneous distillation/extraction with a Likens‐Nickerson apparatus. Extracts were analyzed by gas chromatography coupled with mass spectrometry (GC‐MS) with electron ionization. Apart from the aroma molecules present in all fractions, compounds that are present only in flour or bran, but not in groats, were also found. Furthermore, some compounds were identified only in buckwheat groats but not in buckwheat flour or bran [octanal, (E,E)‐2,4‐heptadienal, (E)‐2‐decenal, and (E,E)‐2,4‐decadienal], others were identified only in husks [(E)‐2‐hexenal, heptanal, (E,E)‐2,4‐hexadienal, phenylacetaldehyde, and alpha‐bisabolol]. 相似文献
19.
Julie Miller Jones 《Cereal Chemistry》2010,87(2):150-154
Whole grains have many health advantages. Therefore, many companies are adding whole grains to their products and consumers are looking for these foods in their diets. Creating regulations that encourages industry to formulate products with whole grains and accurately convey the amount of whole grain in the product to the consumer creates many challenges. Furthermore, the label should give enough information to enable the buyer to know whether of the product is delivering a dietarily significant amount of whole grain. Labeling regulations create a level playing field so that consumers know what is in the product and all manufacturers have the same opportunity to express the benefits for their products. To establish regulations regarding whole grains, there first needs to be an agreement as to which grains are included and which are not. Next, a common definition for whole grains and whole grain foods is needed. The AACC International definition of whole grains is the basis for many definitions adopted by regulatory bodies and used in industry (AACC International Whole Grain Task Force and Definition; http://www.aaccnet.org/definitions/wholegrain.asp ). However, as grains are processed in various ways, attention needs to be paid to the effects of these various processes on the proportions of the kernel required to meet the AACC International definition of whole grains. Furthermore, there needs to be a vehicle that tells the consumer the amount of whole grain in a product. Label declaration of the amount of whole grain required and the amount in the product can help consumers make better food choices. The FDA‐approved health claim for whole grains is one way to label whole grain products. Because it is based on product weight, not dry weight, it gives lower moisture products an unfair competitive advantage. The FDA‐approved health claim also requires a fiber amount; this gives an advantage to products such as wheat and barley that have whole grains with higher fiber contents. Traditional processing of foods, such as the making of bulgur, the pearling of barley, and the nixtamalization of corn offer special challenges to creating definitions and regulations. 相似文献
20.
Phytic acid (myo‐inositol‐1,2,3,4,5,6‐hexakisphosphate) is the most abundant form of phosphorus (P) in cereal grains and is important to grain nutritional quality. In mature rice (Oryza sativa L.) grains, the bulk of phytic acid P is found in the germ and aleurone layer, deposited primarily as a mixed K/Mg salt. Phosphorus components and minerals were measured in whole grain produced by either the rice (Oryza sativa L.) cv. Kaybonnet (the nonmutant control) or the low phytic acid 1‐1 (lpa1‐1) mutant, and in these grains when milled to different degrees (10, 12, 17, 20, 22, and 25%, w/w). Phytic acid P is reduced by 42–45% in lpa1‐1 whole grain as compared with Kaybonnet, but these whole grains had similar levels of total P, Ca, Fe, K, Mg, Mn, and Zn. In both genotypes, the concentration of phytic acid P, total P, Ca, Fe, K, Mg, and Mn in the milled products was reduced by 60–90%, as compared with whole grain. However, a trend was observed for higher (25–40%) total P, K, and Mg concentrations in lpa1‐1 milled products as compared with Kaybonnet milled products. The reduction in whole grain phytic acid P in rice lpa1‐1 is accompanied by a 5‐ to 10‐fold increase in grain inorganic P, and this increase was observed in both whole grain and milled products. Phytic acid P was also reduced by 45% in bran obtained from lpa1‐1 grain, and this was accompanied by a 10‐fold increase in inorganic P. Milling had no apparent effect on Zn concentration. Therefore, while the block in the accumulation of phytic acid in lpa1‐1 seed has little effect on whole grain total P and mineral concentration, it greatly alters the chemistry of these seed constituents, and to a lesser but detectable extent, alters their distribution between germ, central endosperm, and aleurone. These studies suggest that development of a low phytate rice might improve the nutritional quality of whole grain, milled rice and the bran produced during milling. 相似文献