Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Foods ; 13(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38275693

RESUMO

Although the Med-Diet is a healthy diet model, it is affected by current dietary habits. Therefore, new foods with improved nutritional value should be developed to respond to the needs of people following the Med-Diet. This study was focused on developing high-ß-glucan flat bread (bazlama) with a relatively lower GI. A bread wheat (cv. Tosunbey) flour was enriched with the flour of a high-ß-glucan-content hull-less barley (cv. Chifaa) flour (15, 30, 45 and 60%) to develop a functional bazlama. The nutritional and technological properties of bazlama samples enriched with barley flour were compared with the ones produced from bread wheat. All of the barley flour-enriched bazlama samples had higher yellowness values (b*) than the control (both crumb and crust), which is generally preferred by the consumers. Texture results indicated that bazlama samples became harder with the increase in barley flour supplementation level. The results showed that 3 g of ß-glucan can be provided from the barley flour-enriched bazlama samples (at 45 and 60% levels), and this is the limit to carry health claims. The bazlama samples enriched with barley flour were richer in Mg, K, Mn, Fe, and Zn minerals than the control (100% Tosunbey flour). While the glycemic index (GI) of commercial bread wheat and Tosunbey bazlama samples were high (88.60% and 79.20%, respectively), GI values of the bazlama samples enriched with 60% (64.73) and 45% barley flour (68.65) were medium. The lower GI values of barley flour-enriched bazlama samples are probably due to the higher ß-glucan contents of the bazlama samples. Additionally, as the barley flour supplementation level of the bazlama samples increased, the phenolics and antioxidant capacities of free and bound extracts increased compared to bread wheat bazlama. The results indicated that hull-less barley (cv. Chifaa) with high ß-glucan content may be utilized at relatively higher levels (45 and 60%) to produce bazlama with improved nutritional properties.

2.
Foods ; 12(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37761085

RESUMO

The main aim of this study was to investigate the quality and nutritional properties (dietary fiber, phenolic, antioxidant contents, and glycemic index) of breads made from whole wheat flours of colored wheats. White (cultivar Agronomicheskaya 5), red (Element 22), purple (EF 22 and Purple 8), and blue (Blue 10) colored wheats were used in the study. The whole wheat flours of Blue 10 and Purple 8 had higher farinograph stability, lower softening degree, and higher quality numbers indicating that they had better rheological properties. Bread produced from whole wheat flour of blue-colored grain had significantly higher loaf volume and better symmetry, crust color, crumb cell structure, and softness values among others (p < 0.05). The whole wheat bread produced using Element 22 had the highest crust and crumb L* color values, while Purple 8 and EF 22 had the lowest crust and crumb L* color values, suggesting that purple-colored grains have a tendency to make whole wheat bread with darker crust and crumb color. Bread produced from cultivar Blue 10 had the lowest firmness values while Element 22 had the highest firmness values. The highest total phenolic content and antioxidant capacity values were obtained from the whole wheat bread sample from purple-colored wheat (Purple 8). The whole wheat flour of Element 22 had the highest total dietary fiber content among all samples (p < 0.05). The differences between whole wheat bread samples in terms of total dietary fiber and glycemic index were not statistically significant. The results of the present study indicated that colored wheats can be used to produce whole wheat breads with higher nutritional properties and acceptable quality characteristics.

3.
Foods ; 12(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37297355

RESUMO

Intermediate wheatgrass (IWG; Thinopyrum intermedium), a nutritionally dense and sustainable crop, is a promising novel ingredient in bakery applications. The main aim of this study was to investigate the potential of IWG as a novel ingredient in breadmaking. The second aim was to investigate the characteristics of breads substituted with 15, 30, 45, and 60% IWG flour compared to control bread produced using wheat flour. The gluten content and quality, bread quality, bread staling, yellow pigment, and phenolic and antioxidant properties were determined. Enrichment with IWG flours significantly affected the gluten content and quality and bread characteristics. Increased levels of IWG flour substitution significantly decreased the Zeleny sedimentation and gluten index values and increased the dry and wet gluten contents. The bread yellow pigment content and crumb b* colour value increased with the increasing level of IWG supplementation. IWG addition also had a positive effect on the phenolic and antioxidant properties. Bread with 15% IWG substitution had the highest bread volume (485 mL) and lowest firmness values (654 g-force; g-f) compared to the other breads, including the control (i.e., wheat flour bread). The results indicated that IWG has great potential to be used in bread production as a novel, healthy, and sustainable ingredient.

4.
Plants (Basel) ; 12(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37375926

RESUMO

In this study, 21 synthetic hexaploid wheat samples were analyzed and compared for phenolic content (the Folin-Ciocalteu method), phenolic compositions, and antioxidant activity (DPPH, ABTS, and CUPRAC). The aim of the study was to determine the phenolic content and antioxidant activity of synthetic wheat lines developed from Ae. Tauschii, which has a wide genetic diversity, to be used in breeding programs for developing new varieties with better nutritional properties. Bound, free, and total phenolic contents (TPCs) of wheat samples were determined as 145.38-258.55 mg GAE/100 g wheat, 188.19-369.38 mg GAE/100 g wheat, and 333.58-576.93 mg GAE/100 g wheat, respectively. Phenolic compositions were detected by the HPLC system. Gallic acid was found in the highest concentrations in free fractions, whereas gallic, p-coumaric acid, and chlorogenic acid were generally found in the highest concentrations in bound fractions of the synthetic hexaploid wheat samples. The antioxidant activities (AA%) of the wheat samples were evaluated by the DPPH assay. AA% in the free extracts of the synthetic red wheat samples ranged from 33.0% to 40.5%, and AA% values in the bound extracts of the synthetic hexaploid wheat samples varied between 34.4% and 50.6%. ABTS and CUPRAC analyses were also used to measure antioxidant activities. The ABTS values of the free and bound extracts and total ABTS values of the synthetic wheat samples ranged from 27.31 to 123.18, 61.65 to 263.23, and 93.94 to 308.07 mg TE/100 g, respectively. The corresponding CUPRAC values of the synthetic wheats were between 25.78-160.94, 75.35-308.13, and 107.51-364.79 mg TE/100 g. This study revealed that synthetic hexaploid wheat samples are valuable resources for breeding programs for developing new wheat varieties with higher concentrations and better compositions of health-beneficial phytochemicals. The samples w1 (Ukr.-Od. 1530.94/Ae. squarrosa (629)), w18 (Ukr.-Od. 1530.94/Ae. squarrosa (1027)), and w20 (Ukr.-Od. 1530.94/Ae. squarrosa (392)) can be used as a genetic resource in breeding programs to enhance the nutritional quality of wheat.

5.
Plants (Basel) ; 11(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36015476

RESUMO

Wheat as a staple food crop is the main source of micro- and macronutrients for most people of the world and is recognized as an attractive crop for biofortification. This study presents a comprehensive investigation of genomic regions governing grain micro- and macroelements concentrations in a panel of 135 diverse wheat accessions through a genome-wide association study. The genetic diversity panel was genotyped using the genotyping-by-sequencing (GBS) method and phenotyped in two environments during 2017−2018. Wide ranges of variation in nutrient element concentrations in grain were detected among the accessions. Based on 33,808 high-quality single nucleotide polymorphisms (SNPs), 2997 marker-element associations (MEAs) with −log10(p-value) > 3.5 were identified, representing all three subgenomes of wheat for 15-grain concentration elements. The highest numbers of MEAs were identified for Mg (499), followed by S (399), P (394), Ni (381), Cd (243), Ca (229), Mn (224), Zn (212), Sr (212), Cu (111), Rb (78), Fe (63), Mo (43), K (32) and Co (19). Further, MEAs associated with multiple elements and referred to as pleiotropic SNPs were identified for Mg, P, Cd, Mn, and Zn on chromosomes 1B, 2B, and 6B. Fifty MEAs were subjected to validation using KASIB multilocational trial at six sites in two years using 39 genotypes. Gene annotation of MEAs identified putative candidate genes that potentially encode different types of proteins related to disease, metal transportation, and metabolism. The MEAs identified in the present study could be potential targets for further validation and may be used in marker-assisted breeding to improve nutrient element concentrations in wheat grain.

6.
Foods ; 11(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36010514

RESUMO

The total phenolic content, phenolic compositions, and antioxidant capacity in the grain of 40 purple wheat genotypes were studied. In this study, purple wheats were investigated in terms of their composition of free and bound phenolic acids and 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity. The free phenolic content ranged from 164.25 to 271.05 mg GAE/100 g DW and the bound phenolic content was between 182.89-565.62 mg GAE/100 g wheat. The total phenolic content of purple wheat samples ranged from 352.65 to 771.83 mg GAE/100 g wheat. Gallic acid, protocatechuic acid, catechin, 4-hydroxybenzoic acid, syringic acid, ellagic acid, m-coumaric acid, o-coumaric acid, chrysin, caffeic acid, p-coumaric acid, ferulic acid, quercetin, kaempferol, rutin, sinapic acid, and chlorogenic acid were detected by HPLC system. Gallic acid, benzoic acid derivatives, and dominant phenolics, which are frequently found in cereals, were also dominant in purple wheat samples and were found in free fractions. The antioxidant capacity was assessed using the DPPH method. The antioxidant capacity (AA%) in the free phenolic extracts of the purple wheats was between 39.7% and 59.5%, and the AA% values of bound phenolic extract of the purple wheat varied between 42.6% and 62.7%. This study suggested that purple wheat samples have high phenolic compound content as antioxidant potential and therefore consumption of purple wheat-containing food products may provide health benefits.

7.
Plants (Basel) ; 11(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35050037

RESUMO

Western Siberia is one of the major spring wheat regions of Russia, cultivating over 7 Mha. The objective of the study was to evaluate the variation of macro- and microelements, and of trace metals in four distinct groups of genetic resources: primary synthetics from CIMMYT (37 entries), primary synthetics from Japan (8), US hard red spring wheat cultivars (14), and material from the Kazakhstan-Siberian Network on Spring Wheat Improvement (KASIB) (74). The experiment was conducted at Omsk State Agrarian University, using a random complete block design with four replicates in 2017 and 2018. Concentrations of 15 elements were included in the analysis: macroelements, Ca, K, Mg, P, and S; microelements, Fe, Cu, Mn, and Zn; toxic trace elements, Cd, Co, Ni; and trace elements, Mo, Rb, and Sr. Protein content was found to be positively correlated with the concentrations of 11 of the elements in one or both years. Multiple regression was used to adjust the concentration of each element, based on significant correlations with agronomic traits and macroelements. All 15 elements were evaluated for their suitability for genetic enhancement, considering phenotypic variation, their share of the genetic component in this variation, as well as the dependence of the element concentration on other traits. Three trace elements (Sr, Mo, and Co) were identified as traits that were relatively easy to enhance through breeding. These were followed by Ca, Cd, Rb, and K. The important biofortification elements Mn and Zn were among the traits that were difficult to enhance genetically. The CIMMYT and Japanese synthetics had significantly higher concentrations of K and Sr, compared to the local check. The Japanese synthetics also had the highest concentrations of Ca, S, Cd, and Mo. The US cultivars had concentrations of Ca as high as the Japanese synthetics, and the highest concentrations of Mg and Fe. KASIB's germplasm had near-average values for most elements. Superior germplasm, with high macro- and microelement concentrations and low trace-element concentrations, was found in all groups of material included.

8.
J Sci Food Agric ; 98(15): 5677-5682, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29736935

RESUMO

BACKGROUND: Since the common protease substrates did not give satisfactory results for the determination of Sunn pest protease activity in damaged wheat, different peptide substrates derived from the repeated sequences of high molecular weight glutenin subunits were synthesized. RESULTS: Hydrolysis of peptides by pest protease was determined by high-performance liquid chromatography. Among three peptides having the same consensus motifs, peptide1 (PGQGQQGYYPTSPQQ) showed the best catalytic efficiency. A novel assay was described for monitoring the enzymatic activity of protease extracted from damaged wheat flour. The selected peptide was labeled with a fluorophore (EDANS) and quencher (Dabcyl) to display fluorescence resonance energy transfer. The proteolytic activity was measured by the change in fluorescence intensity that occurred when the protease cleaved the peptide substrate. Furthermore, the assay developed was modified for rapid and easy detection of bug damage in flour. Flour samples were suspended in water and mixed with fluorescence peptide substrate. After centrifugation, the fluorescence intensities of the supernatants, which are proportional to the protease content of the flour, were determined. CONCLUSION: The total analysis time for the assay developed is estimated as 15 min. The assay developed permits a significant decrease in time and labor, offering sensitive detection of Sunn pest damage in wheat flour. © 2018 Society of Chemical Industry.


Assuntos
Endopeptidases/química , Ensaios Enzimáticos/métodos , Farinha/parasitologia , Heterópteros/enzimologia , Proteínas de Insetos/química , Peptídeos/química , Doenças das Plantas/parasitologia , Triticum/parasitologia , Animais , Biocatálise , Farinha/análise , Fluorescência , Heterópteros/fisiologia , Hidrólise , Sementes/química , Sementes/parasitologia , Triticum/química
9.
Food Chem ; 246: 150-155, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29291833

RESUMO

Three different wheat cultivars (Bezostaya, Eser and Cesit-1252) at four maturity stages were processed into firik which is a whole wheat-based ethnic food by using traditional cooking method. Some nutritional and antinutritional (moisture, ash, protein, fructans, dietary fibers, phenolic contents and antioxidant activity) properties of firiks were investigated. A significant increase was observed for the hectoliter and 1000 kernel weights whereas a decrease for ash and protein contents by increased maturation level. It was found that immature wheats especially at early stages of kernel development are rich sources of functional nutrients such as total dietary fiber (17.3-20.4%), fructans (4.1-7.2%), total phenolics (4602.5-4838.3 mgGAE/kg) and antioxidants (729.2-782.8 µmolTE/100 g) besides having lower phytic acid contents (498.6-604.9 mg/100 g).


Assuntos
Ácido Fítico/análise , Triticum/química , Triticum/crescimento & desenvolvimento , Antioxidantes/análise , Culinária , Fibras na Dieta/análise , Análise de Alimentos , Frutanos/análise , Valor Nutritivo , Fenóis/análise , Proteínas de Plantas/análise , Grãos Integrais/química
10.
Food Chem ; 174: 173-9, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25529667

RESUMO

The optimum reaction conditions (temperature and pH) for the preparation of cross-linked (CL) corn and wheat starches with maximum resistant starch (RS) content were investigated by using response surface methodology (RSM). According to the preliminary results, five levels were selected for reaction temperature (38-70 °C) and pH (10-12) in the main study. RS contents of the CL corn and wheat starch samples increased with increasing temperature and pH, and pH had a greater influence on RS content than had temperature. The maximum RS content (with a maximum p value of 0.4%) was obtained in wheat starch cross-linked at 38 °C and pH 12. In the case of CL corn starch, the optimum condition was 70 °C and pH 12. CL corn and wheat starch samples were also produced separately under the optimum conditions and their RS contents were 80.4% and 83.9%, respectively. These results were also in agreement with the values predicted by RSM.


Assuntos
Amido/química , Triticum/química , Zea mays/química , Concentração de Íons de Hidrogênio , Fósforo/análise , Amido/análise , Temperatura
11.
J Sci Food Agric ; 94(12): 2562-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24497201

RESUMO

BACKGROUND: Acrylamide is a possible carcinogen and known to form in heat-treated carbohydrate-rich foods. This study was designed to investigate the effects of different ingredients (reducing sugars, chemical leavening agents, citric acid), processing conditions (feed moisture content: 22, 24 or 26%, exit die temperature: 110, 150 °C), and extrusion cooking methods (with or without CO2 injection) on acrylamide formation. RESULTS: The type of reducing sugar did not have a considerable effect on acrylamide formation, while increased exit die temperature had a promoting effect. Addition of chemical leavening agents (sodium bicarbonate and ammonium bicarbonate) into formulations increased acrylamide formation levels. The addition of citric acid prevented acrylamide formation, but its effect on textural properties was detrimental. Acrylamide levels of extrudates decreased gradually with increasing feed moisture in all formulations. Acrylamide content of extrudates produced with 22% feed moisture decreased by 61% in the CO2 injection method compared to conventional extrusion. Furthermore, an 82% decrease in acrylamide content was observed with the combined effect of CO2 injection and increasing feed moisture content from 22 to 24% and decreased below the limit of quantification with a further increase in feed moisture. CONCLUSION: A substantial decrease in final acrylamide level is probably due to restriction of two major steps of acrylamide formation: dehydration and decarboxylation.


Assuntos
Acrilamida/análise , Bicarbonatos , Metabolismo dos Carboidratos , Dióxido de Carbono , Ácido Cítrico , Culinária , Zea mays/química , Carboidratos , Descarboxilação , Dessecação , Dieta , Temperatura Alta , Humanos , Reação de Maillard , Bicarbonato de Sódio , Água
12.
J Agric Food Chem ; 59(6): 2462-70, 2011 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-21323348

RESUMO

Glutenin hydrolyzing proteinases (GHPs) have been purified, by affinity chromatography, from wheat seeds damaged by the Sunn bug Eurygaster integriceps (Hemiptera, Scutelleridae). A 28 kDa protein was partially sequenced by mass spectrometry and Edman degradation which showed homology to serine proteases from various insects. Three full length clones were obtained from cDNA isolated from Sunn bug salivary glands using degenerate PCR based on the sequences obtained. The cleavage site of the protease was determined using recombinant and synthetic peptides and shown to be between the consensus hexapeptide and nonapeptide repeat motifs present in the high molecular weight subunits of wheat glutenin (PGQGQQ∧GYYPTSLQQ). Homology models were generated for the three proteinases identified in this study using the high resolution X-ray structure of a crayfish (Pontastacus leptodactylus) trypsin complexed with a peptide inhibitor as template (PDB accession 2F91). The novel specificity of this protease may find applications in both fundamental and applied studies.


Assuntos
Heterópteros/enzimologia , Proteínas de Insetos/química , Serina Proteases/química , Sequência de Aminoácidos , Animais , Glutens/química , Glutens/metabolismo , Heterópteros/genética , Heterópteros/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Glândulas Salivares/química , Glândulas Salivares/enzimologia , Alinhamento de Sequência , Serina Proteases/genética , Serina Proteases/metabolismo , Especificidade por Substrato
13.
Int J Food Sci Nutr ; 60(6): 449-57, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19212857

RESUMO

Three different commercial starches (Hylon VII, Novelose 330 and CrystaLean) were incorporated into the bread formulation at different levels and their effects on the rheological and baking properties and resistant starch contents of breads were evaluated. Starch-supplemented doughs were weaker and absorbed more water than those of the base flour. Loaf volumes of the breads decreased above the 10% level for Novelose and above the 20% level for Hylon VII and CrystaLean supplementation. Commercial starches did not have a substantial deteriorative effect on crumb color, external appearance and symmetry of breads. Crust color values decreased at a 30% addition level in Novelose-supplemented and CrystaLean-supplemented breads and above a 10% addition level in Hylon VII-supplemented breads. Firmness of breads increased above the 10% level for Novelose and above the 20% level for Hylon VII and CrystaLean supplementation. Resistant starch contents of the breads (after 1 and 7 days storage) increased significantly as the addition level of commercial starches increased.


Assuntos
Pão , Dieta , Carboidratos da Dieta , Fibras na Dieta , Suplementos Nutricionais , Farinha/análise , Amido , Cor , Culinária , Carboidratos da Dieta/análise , Fibras na Dieta/análise , Farinha/normas , Qualidade dos Alimentos , Dureza , Humanos , Reologia , Amido/análise , Água
14.
J Agric Food Chem ; 56(16): 7285-92, 2008 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-18593174

RESUMO

In this study, samples of 18 ancient wheat (12 emmer, 6 einkorn) and 2 bread wheat varieties grown in different regions of Turkey were examined for their total phenolics and flavonoids, phenolic acids, lutein, total yellow pigment, and total radical scavenging capacities against ABTS cation. Results showed that health beneficial phytochemicals and total antioxidant capacities were generally significantly different in emmer and einkorn wheat groups. Remarkably higher total antioxidant activity (18.31 +/- 1.31 micromol Trolox equiv/g), total phenolics (6.33 +/- 0.98 micromol gallic acid equiv/g), ferulic acid (662.95 +/- 61.07 microg/g), and flavonoids (1.61 +/- 0.34 micromol catechin equiv/g) content were detected in emmer wheat samples (n = 12), suggesting that they may have high potential for utilization as a novel grain, rich in natural antioxidants. In addition, quite high levels of lutein (7.33 +/- 2.43 microg/g) of einkorn samples (n = 6) hold the potential of developing high-lutein bakery products to considerably raise the dietary intake of carotenoids. These findings for ancient wheat varieties are considered to be very useful in breeding programs for selecting and breeding wheat varieties for higher concentration and better composition of health-beneficial phytochemicals.


Assuntos
Antioxidantes/análise , Sementes/química , Triticum/química , Benzotiazóis , Pão/análise , Flavonoides/análise , Hidroxibenzoatos/análise , Luteína/análise , Especificidade da Espécie , Ácidos Sulfônicos , Turquia
15.
Food Chem ; 109(2): 355-60, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26003358

RESUMO

For investigating the carryover of some organophosphorus pesticide residues in the cereal food chain from grain to consumer, a study was set up on durum wheat, semolina and pasta. Pesticide-free durum wheat was placed into a small-scale model of a commercial storage vessel and treated with pesticides (malathion, fenitrothion, chlorpyrifos methyl, and pirimiphos methyl) according to the raw material legislation of Turkey. The residue levels of insecticides were determined in wheat, semolina, and spaghetti produced from stored wheat at various time intervals during five months of storage. A multiresidue analysis was performed using GC equipped with an NPD. The confirmation was performed by GC-MS. The residue levels of insecticides in wheat exceeded the maximum residue limits (MRLs) for wheat. The storage period was generally not effective enough to reduce the residues in wheat to levels below the MRLs. Although a considerable amount of the insecticides remained in the semolina, spaghetti processing significantly reduced residue concentrations in general. Pirimiphos methyl was the most persistent of the insecticides and comparatively less substantial loss occurred during milling and spaghetti processing due to its physicochemical properties.

16.
Nahrung ; 48(1): 19-24, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15053346

RESUMO

The objective of this research was to investigate the extrudability of waxy hulless barley flour under various extrusion conditions. Waxy hulless barley flour was processed in a laboratory-scale corotating twin-screw extruder with different levels of feed moisture content (22.3, 26.8, and 30.7%) and die temperature (130, 150, and 170 degrees C) to develop a snack food with high beta-glucan content. The effects of extrusion condition variables (screw configuration, moisture, and temperature) on the system variables (pressure and specific mechanical energy), the extrudate physical properties (sectional expansion index, bulk density), starch gelatinization, pasting properties (cold peak viscosity, trough viscosity, and final viscosity), and beta-glucan contents were determined. Results were evaluated by using response surface methodology. Increased extrusion temperature and feed moisture content resulted in decreases in exit die pressure and specific mechanical energy values. For extrudates extruded under low shear screw configuration (LS), increased barrel temperature decreased sectional expansion index (SEI) values at both low and high moisture contents. The feed moisture seems to have an inverse relationship with SEI over the range studied. Bulk density was higher at higher moisture contents, for both low and high barrel temperatures, for samples extruded under high shear screw configuration (HS) and LS. Cold peak viscosities (CV) were observed in all samples. The CV increased with the increase in extrusion temperature and feed moisture content. Although beta-glucan contents of the LS extrudates were comparable to that of barley flour sample, HS samples had generally lower beta-glucan contents. The extrusion cooking technique seems to be promising for the production of snack foods with high beta-glucan content, especially using LS conditions.


Assuntos
Manipulação de Alimentos/métodos , Hordeum/química , Fenômenos Químicos , Físico-Química , Indústria Alimentícia , Glucanos/análise , Solubilidade , Temperatura , Viscosidade , Água/análise
17.
Int J Food Sci Nutr ; 55(8): 641-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16019309

RESUMO

Effects of gamma irradiation at doses of 1 kGy, 5 kGy, and 10 kGy on water absorption properties, cooking quality and electrophoretic patterns of insoluble proteins of red and green lentil samples were investigated. The densitometric analysis indicated that the effects of irradiation on sodium dodecyl sulfate-polycrylamide gel electrophoresis patterns of red and green lentil proteins were not significant. Generally, a 1 kGy irradiation dose did not significantly affect the water absorption properties of the lentil samples while significant increases were observed at the 5 kGy level. The dry and wet cooking times were found to be significantly decreased, as the irradiation level increased in all red and green lentil samples.


Assuntos
Proteínas Alimentares/efeitos da radiação , Lens (Planta)/efeitos da radiação , Água/fisiologia , Absorção , Eletroforese em Gel de Poliacrilamida/métodos , Irradiação de Alimentos , Conservação de Alimentos/métodos , Raios gama , Temperatura Alta , Lens (Planta)/fisiologia , Cloreto de Sódio/metabolismo , Solubilidade
18.
Nahrung ; 47(4): 238-42, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-13678261

RESUMO

The contribution of the three-dimensional structures of one heptapeptide (PQPQPFP) sequence and one pentapeptide (PQQPY) repeat sequence of alpha/beta-gliadins, one heptapeptide (PQQPFPQ) repeat sequence of gamma-gliadins, two heptapeptide (PQQPPFS and QQQQPVL) repeat motifs of low-molecular-weight (LMW) subunits and a tetrapeptide sequence in polyQ region of S-rich prolamins to their conformations are investigated by using the recently developed multicanonical simulation procedure. Ramachandran plots were prepared and analysed to predict the relative occurrence probabilities of gamma-tutn, gamma-turn, and helical structures. The probability of inverse 7-turn was generally higher than that of beta-turns in all sequences investigated. Occurrence probability of helical structure in the repetitive domain of gliadins was low. Structural predictions of QQQQPVL sequence of LMW-glutenin subunits and QQQQ sequence in the polyQ region of S-rich prolamins indicate the presence of helical structures with the probability of >20%. The probability of helical structure significantly decreased around 100 degrees C.


Assuntos
Gliadina/química , Glutens/análogos & derivados , Glutens/química , Sequência de Aminoácidos , Modelos Moleculares , Estrutura Molecular , Peso Molecular , Estrutura Secundária de Proteína , Homologia Estrutural de Proteína
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA