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1.
Molecules ; 25(13)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32630230

RESUMO

The benefit of not containing the gluten complex protein also provides problems with the achievement of typical and proper texture, especially in bakery products. Ultrasound (US) treatment has been previously studied on buckwheat as assistance treatment facilitating the release of antioxidant compounds. However, there is no study regarding the changes occurring in US-treated buckwheat grains regarding the structure-creating capacity, like water absorption, gelling, and pasting. The aim of this study is to the impact of US-treatment of buckwheat grains at 1:10, 1:5, and 1:2.5 solid: liquid ratio (in water). The particle size distribution, water absorption index (WAI), water solubility index (WSI), swelling power (SP), pasting characteristics, color, soluble, insoluble and total polyphenols content (SPC, IPC, TPC) and antioxidant activity (DPPH) were assessed in resulting flours. US-treatment caused specific agglomeration, resulting in bigger particles for 1:5, and 1:2.5 ratio treated samples, while higher dilution (1:10) increased smaller particle size fractions. The WAI and SP were the highest for the1:5 solid: liquid ratio sample, and the same sample revealed the highest peak viscosity, breakdown, and setback values. The ultrasound treatment increased the WSI, which was positively correlated with insoluble polyphenols content. The soluble polyphenols content decreased, and insoluble polyphenols content increased in all ultrasound treated samples. The DPPH scavenging activity remaining in grain after US treatment was lowered compared to the control sample. The relocation of pigments resulted in a redness and yellowish increase in all treated samples, while lightness was also increased but was most pronounced for a 1:10 ratio treated sample. The results suggest that ultrasound treatment of grain can improve the essential functional properties of buckwheat flour.


Assuntos
Antioxidantes/análise , Fagopyrum/química , Farinha/análise , Manipulação de Alimentos/métodos , Fenóis/análise , Sementes/química , Ondas Ultrassônicas , Antioxidantes/efeitos da radiação , Cor , Fagopyrum/efeitos da radiação , Farinha/efeitos da radiação , Fenóis/efeitos da radiação , Sementes/efeitos da radiação
2.
Int J Biol Macromol ; 145: 712-721, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31862371

RESUMO

Impact of high-power sonication (HPS) as pretreatment in extraction and some physicochemical properties of proteins from soybean flakes, flour of soybean, chickpea, and kidney bean was evaluated. Soybean flakes and flours from soybean, chickpea, and kidney bean were dispersed in distilled water (1.10 w/v) and sonicated at two power densities (PD) of 2.5 and 4.5 W/cm3 for 5 min continuously. Proteins were extracted at pH range 8-8.5. PD 2.5 and 4.5 W/cm3 significantly increased protein extraction yields from soy flakes to 29.03% and 25.87%, respectively, compared to 15.28% for unsonicated controls, but did not increase for flours. Freeze-dried spent substrates at higher PD sonication aggregated in size. Free sulfhydryl content for both sonicated and unsonicated soy flakes and flour were similar but increased in chickpea and kidney bean when HPS of 4.5 W/cm3 was applied, indicating the unfolding of protein structure. The protein band patterns for sonicated and unsonicated legumes proteins were found to be similar, indicating no peptide profile alterations by HPS. However, circular dichroism analysis showed changes in secondary structure composition in extracted kidney bean protein causing unfolding and destabilizing the native structure. The secondary structure composition for soy flakes and flour protein and chickpea protein remained unchanged.


Assuntos
Farinha/efeitos da radiação , Manipulação de Alimentos , Proteínas de Plantas/química , Sonicação , Cicer/química , Humanos , Phaseolus/química , Proteínas de Plantas/efeitos da radiação , Glycine max/química , Água/química
3.
Food Chem ; 233: 467-475, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28530600

RESUMO

The properties and viscosity-reduction mechanism of corn flour irradiated by electron beam have not been understood properly. Here, we investigate the effects of electron beam irradiation (EBI) on the gelatinization and physicochemical properties of corn flour irradiated by 0-5.40kGy of electron beam. The total starch and crude fiber contents of corn flour decreased significantly (P<0.05) after EBI treatment, while the moisture and reducing sugar contents increased significantly (P<0.05). EBI caused perforations on the corn flour particle surfaces, and the irradiated parts of the particles would gradually peel off and afford smooth surfaces, spherical structures, and smaller sizes. Molecular chains of corn flour broke owing to EBI. After irradiation, the pasting peak viscosity decreased dramatically (P<0.01) from 1251.74 to 7.16Pa·s, showing that the gelatinization of corn flour was completely inhibited. Thus, EBI can be used to inhibit the gelatinization of corn flour, which may be beneficial for industrial and food formulations.


Assuntos
Elétrons , Farinha/efeitos da radiação , Irradiação de Alimentos , Zea mays , Amido/química , Viscosidade
4.
Food Chem ; 234: 276-284, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28551237

RESUMO

Freeze dried raw (FDR) and freeze dried blanched (FDB) Amorphophallus paeoniifolius flours were irradiated at doses of 3, 6 and 12kGy. The irradiated flours were investigated for physicochemical, pasting, textural, thermal and morphological properties. Reduction in amylose content was observed with increasing irradiation dose. Carboxyl content of the flours increased significantly at higher doses. Decline in lightness (L∗) and increase in redness (a∗) were found to increase with the elevation of dosage. Irradiation caused reduction in the values of pasting parameters of freeze dried raw as well as freeze dried blanched samples. Hardness of the flour gels exhibited increase at all the doses except at 3kGy. Decrease in onset gelatinization temperature of both FDR and FDB flours was observed with increasing irradiation dose. FDR as well as FDB flours exhibited increasing trend in their enthalpy (ΔHgel) values following irradiation treatment. Raman spectroscopy revealed that no new functional groups were introduced by irradiation treatment. However, band intensity of functional groups in irradiated FDR flours was reduced with increment of dose.


Assuntos
Amorphophallus/química , Farinha/efeitos da radiação , Raios gama , Amilose/química , Liofilização , Géis/química , Viscosidade
6.
Genet Mol Res ; 13(4): 9024-31, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25366793

RESUMO

With 300 Gy of [(60)Co] γ-ray radiation of dry wheat seeds of Vortex 9722, the protein content, wet gluten content, sedimentation value, and hardness variation were analyzed in 341 lines in M4. Using over population mean ± 2X standard deviation as the screening standard, 8 lines with higher protein and wet gluten content and 4 lines with lower protein and wet gluten content were selected. In the M5 generation, the quality traits - silty parameters and high molecular weight glutenin subunits (HMW-GS) - were further analyzed in these 12 lines. The results showed that in the M5 generation, the quality traits in some variants were significantly different from those in the parents; the farinograms varied greatly. Eleven variants had significantly different HMW-GS bands compared to their parents. The parents had a HMW-GS composition of 5 + 14 + 15 + 12 + 9, and the variants had HMW-GS of 11 + 5 + 7 + 9 + 12 subunits or 1 + 5 + 7 + 8 + 12 subunits, indicating that the glutenin loci of these lines were mutated.


Assuntos
Radioisótopos de Cobalto , Glutens/genética , Mutação , Triticum/genética , Triticum/efeitos da radiação , Eletroforese em Gel de Poliacrilamida , Farinha/análise , Farinha/efeitos da radiação , Glutens/química , Glutens/metabolismo , Padrões de Herança/genética , Peso Molecular , Fenótipo , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Sementes/genética , Sementes/metabolismo , Sementes/efeitos da radiação , Especificidade da Espécie , Triticum/classificação
7.
Food Chem ; 154: 230-7, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24518337

RESUMO

Hygienic quality of Tunisian pearl millet flour is always of major concern to consumers as well as all involved in the production, processing and distribution sectors. In the present study, the microbiological and biochemical properties of this food were examined following gamma-radiation. The D10-values for the Total Aerobic Plate Count, yeasts and moulds were respectively 1.5 and 3.7kGy. Furthermore, millet flour is commonly susceptible to mycotoxin contaminations, so the Ochratoxin A residues were also investigated; a reduction of 74% was observed with 10kGy. Moreover, the radiation process did not significantly alter fatty acids composition of the millet flour as obtained with Gas chromatography-flame ionisation detector technic. The peroxide value had increased from 26.16 to 34.43meqO2/kg with 3kGy. At 1kGy, we noticed an important loss of vitamin A of about 88.6%. In contrast, the total phenolic content, the ABTS-RSA and the DPPH-RSA of the radiated millet flour exhibited non-significant changes (p<0.05).


Assuntos
Antioxidantes/química , Irradiação de Alimentos/métodos , Panicum/microbiologia , Panicum/efeitos da radiação , Aminoácidos/análise , Ácidos Graxos/análise , Farinha/análise , Farinha/microbiologia , Farinha/efeitos da radiação , Contaminação de Alimentos/análise , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Fungos/efeitos da radiação , Raios gama , Micotoxinas/análise , Micotoxinas/química , Panicum/química , Pennisetum , Fenóis/análise , Tunísia , Vitamina A/análise
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 63(4): 888-90, 2006 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-16500143

RESUMO

We revealed free radicals in wheat flour before and after gamma-ray irradiation and their thermal behavior during heat-treatment using electron spin resonance (ESR) spectroscopy. The ESR spectrum of wheat flour before irradiation consists of a sextet centered at g = 2.0 and a singlet signal at the same g-value position. The first one is attributable to a signal with hyperfine (hf) interactions of Mn2+ ion (hf constant: 7.4 mT). The second is originated from carbon-centered radical. Upon gamma-ray irradiation, however, a new signal with two triplet lines at the low and high field ends was detected in wheat flour on top of the Mn2+ sextet lines. We analyzed the triplet ESR lines as powder spectra (rhombic g-tensor symmetry) with nitrogen (14N) hyperfine interactions. This indicates that a new organic radical was induced in the conjugated protein portion of wheat flour by the gamma-ray irradiation. Intensity of the organic free radical at g = 2.0 detected in irradiated wheat flour increased monotonically by the thermal treatment. The analysis of the time-dependent evolution and decay process based on the theory of transient phenomena as well as the nonlinear least-squares numerical method provided a unique time constant for the radical evolution and decay in wheat flour during the heat-treatment.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica , Farinha/efeitos da radiação , Irradiação de Alimentos , Radicais Livres , Raios gama , Triticum/efeitos da radiação , Relação Dose-Resposta à Radiação , Triticum/química
9.
Plant Foods Hum Nutr ; 46(2): 181-6, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7855086

RESUMO

Chemical and nutritional characteristics of irradiated and nonirradiated cowpea bean at 0.2 kGy submitted to several thermal treatments were studied. The cowpea bean flours irradiated at 0.2 kGy were superior to those non-irradiated concerning digestibility and the flours submitted to microwave oven were superior to those cooked under low pressure, autoclaved or even raw from the nutritional point of view. As to the presence of anti-nutritional factors, the results showed that the variety of cowpea bean under research presented neither trypsin inhibitor nor haemagglutinin activity, however, regarding tannin, a 0.006% content was found and considered negligible.


Assuntos
Culinária , Fabaceae , Farinha/análise , Irradiação de Alimentos , Plantas Medicinais , Análise de Variância , Animais , Bovinos , Proteínas Alimentares , Digestão , Eritrócitos/enzimologia , Farinha/efeitos da radiação , Hemaglutininas/análise , Temperatura Alta , Micro-Ondas , Valor Nutritivo , Ratos , Ratos Wistar , Tripsina/sangue , Inibidores da Tripsina/análise
10.
Toxicol Eur Res ; 5(1): 17-21, 1983 Jan.
Artigo em Francês | MEDLINE | ID: mdl-6857654

RESUMO

Blood samples were collected all six weeks from the tip of the tail of AKR mice fed with irradiated or non irradiated wheat flour. Haematocrit, red and white blood cell counts and differential white cell counts were determined and the activity of p-phenylenediamine oxidase was measured in the serum. No effect attributed to the diet could be demonstrated. We propose a method to detect antemortem the appearance of the AKR leukemia.


Assuntos
Contagem de Células Sanguíneas , Farinha/toxicidade , Irradiação de Alimentos/efeitos adversos , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/sangue , Animais , Feminino , Farinha/efeitos da radiação , Hematócrito , Contagem de Leucócitos , Masculino , Camundongos , Camundongos Endogâmicos AKR , Fatores de Tempo , Triticum
11.
Toxicol Eur Res ; 5(1): 27-30, 1983 Jan.
Artigo em Francês | MEDLINE | ID: mdl-6857655

RESUMO

Mouse of AKR strain received in their diet, 50% of wheat flour irradiated at 75000 rads or 50% of non irradiated flour during their lifetime. In this part, were analyzed data obtained through 7 consecutive mating : size of litters, weight and growth of pups, lethality in the first days, number of still-born, sex ratio. It was any significant difference between the two groups although many data were better in the test group.


Assuntos
Farinha/toxicidade , Irradiação de Alimentos/efeitos adversos , Reprodução , Animais , Peso ao Nascer/efeitos da radiação , Feminino , Farinha/efeitos da radiação , Crescimento/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos AKR , Gravidez , Reprodução/efeitos da radiação , Razão de Masculinidade , Triticum
12.
Toxicol Eur Res ; 5(1): 7-15, 1983 Jan.
Artigo em Francês | MEDLINE | ID: mdl-6857657

RESUMO

Mouse of AKR strain were fed with wheat flour irradiated at 75.000 rads or with nonirradiated flour during their lifetime. In this first part were analyzed : bodyweight, morbidity, mortality, organ's histology. Were established : higher bodyweight in all animals fed with irradiated flour, this increase is statistically significant only in males and a longer time life in all animals of this group, this last difference is significant in females and in animals together without distinction of sex.


Assuntos
Farinha/toxicidade , Irradiação de Alimentos/efeitos adversos , Animais , Peso Corporal , Eczema/etiologia , Feminino , Farinha/efeitos da radiação , Expectativa de Vida , Masculino , Camundongos , Camundongos Endogâmicos AKR , Tamanho do Órgão , Fatores Sexuais , Triticum
13.
Toxicol Eur Res ; 5(1): 23-6, 1983 Jan.
Artigo em Francês | MEDLINE | ID: mdl-6190265

RESUMO

The livers and the pancreas of AKR mice fed with irradiated or non-irradiated wheat flour were homogenized to measure the activities of the follow enzymes : alkaline phosphatase, acid phosphatase, glucose . 6 . phosphate dehydrogenase, amylase. No effect could be demonstrated.


Assuntos
Farinha/toxicidade , Irradiação de Alimentos/efeitos adversos , Fígado/enzimologia , Pâncreas/enzimologia , Fosfatase Ácida/metabolismo , Fosfatase Alcalina/metabolismo , Amilases/metabolismo , Animais , Feminino , Farinha/efeitos da radiação , Glucosefosfato Desidrogenase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos AKR , Triticum
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