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1.
Prep Biochem Biotechnol ; : 1-11, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950423

RESUMO

Some factors in the salting-out extraction (SOE) method play a major role. The aim of this study was to investigate the interaction effects of the phase forming components and consequently select the best conditions to achieve a highly efficient recovery of phenolic compounds from walnut green husks (Juglans regia L.) using mixtures of ethanol and aqueous ammonium sulfate solutions. According to the results that were analyzed by response surface methodology, the optimal extraction conditions were obtained at ethanol: salt: water ratio of 34.8: 15.1: 54.4 (w/w) at a pH of 6-6.5 and 25 °C. At the optimal conditions, the overall phenolic and flavonoid content, and antioxidant activity were significantly higher than obtained by the conventional method. In addition, at a higher scale (i.e., 5 kg), similar results were obtained. Thus, it can be concluded that SOE has the potential to be scaled up for the simultaneous separation and purification of compounds from plant biomass. This paper is addressing extraction techniques, measurement, and characterization of new natural phenolic compounds from an agricultural by-product and valorization of waste.

2.
Int J Biol Macromol ; 253(Pt 7): 127545, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37863148

RESUMO

This study aimed to optimize the extraction of pectin and phenolics from walnut green husk using the electrohydrodynamic method (EHD) and assess its impact on the chemical structure and properties of pectin. A comparative analysis was conducted with acidified water as the conventional extraction method. The results revealed significant improvements under the optimal EHD conditions (36.8 min, 17.5 kV, 90 °C), leading to a remarkable increase of over 64 % in pectin yield and >20 % in total phenolic content in half the extraction time. Chemical analysis showed that pectin samples contain 1.4-1.7 % ash, 3.6-4.6 % protein, over 90 % carbohydrates, and a galacturonic acid content ranging from 67.7 to 68.2 g/g. Both extraction methods yielded pectin with a high methoxyl degree, comparable thermal stability, and amorphous structure. EHD treatment resulted in reduced molecular weight, degree of esterification, water-holding capacity, and emulsion stability of pectin while enhancing its solubility and emulsion capacity. In summary, EHD treatment significantly improved extraction yield and changed the functionality of pectin, particularly in terms of emulsion activity. This alteration should be considered when utilizing pectin for specific applications.


Assuntos
Juglans , Pectinas , Pectinas/química , Emulsões/química , Peso Molecular , Água
3.
Int J Biol Macromol ; 247: 125760, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37453643

RESUMO

Acorn (Quercus brantii) is a rich source of starch. Since the presence of lipids affects the physicochemical properties of starch and the extraction of nutritious acorn oil and its starch is economical, it's essential to study the acorn starch characteristics before and after oil extraction. Firstly, the best condition for reaching the maximum extraction yield of acorn starch (AS) was determined, and defatted acorn starch (DAS) was extracted in the same conditions. Then the physicochemical properties of both samples were compared. The structural properties were investigated by Scanning Electron Microscopy images. The maximum yield of AS was obtained in a 1:10 ratio (acorn flour: water) at 45 °C and 180 min. Results demonstrated significant differences between color parameters and fat content (0.65 ± 0.04 and 12 ± 0.02) of AS and DAS. Also, DAS had higher swelling power, solubility, and lower turbidity than AS. The X-ray diffraction pattern showed that AS was C-type with relative crystallinity of 27.77 %. Pasting, thermal, and textural properties reflected the higher viscosity, gelatinization, retrogradation, and hardness for DAS compared to AS. Consequently, all of these analyses exhibited structural changes in acorn starch by removing lipids from acorn flour and provided essential information for further applications of acorn starch in different industries.


Assuntos
Quercus , Amido , Amido/química , Quercus/química , Difração de Raios X , Viscosidade , Solubilidade , Lipídeos
4.
Int J Biol Macromol ; 233: 123526, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736973

RESUMO

In the current study, native and different fatty acid-esterified waxy maize starches (octanoate, myristoate, and stearoate), followed by an OSA-potato starch (as an industrial emulsifier) were used to prepare sunflower oil-in-water (O/W) emulsion. The effect of emulsifier type and concentration were evaluated on properties of emulsions in terms of mean droplet size, droplet size distribution, and creaming index. To prepare the emulsion, the emulsifier to oil ratios of 1.25 and 0.5 for octanoate and industrial emulsifier (control) were considered as the selected formulations based on the lowest creaming index (2.63 and 0 %, respectively). The influence of various pHs and ionic strengths on droplet size, span and zeta potential value was similar for both produced emulsions. Therefore, the fatty acid-esterified starch could be suggested as a promising environmentally friendly alternative to industrial emulsifiers for fabrication of emulsions with similar stability.


Assuntos
Caprilatos , Zea mays , Emulsões , Ácidos Graxos , Emulsificantes , Amido , Amilopectina , Água , Tamanho da Partícula
5.
J Food Sci Technol ; 59(11): 4380-4389, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36193461

RESUMO

Aqueous two-phase system (ATPS) composed of polyethylene glycol (PEG) and K2HPO4 solutions was used to extract saponin from sugar beet root. Extraction yield, purity and foam capacity of saponin were optimized according to response surface methodology (RSM). Analysis of liquid chromatography-mass spectrometry (LC-MS) showed that purified saponins were composed of hederagenin, akebonoic acid and oleanolic acid. Addition of 0.02 g sugar beet root saponin to one liter of malt beverage caused a considerable increase in foam volume and stability compared to malt beverage samples containing 0.1 g/L propylene glycol alginate (PGA). Malt beverages containing saponin showed higher turbidity, bitterness and overall sensory acceptance. Moreover, no significant changes in malt drink pH and °Brix were observed due to saponin addition. Adding lemon flavor caused a decrease in foam stability and sensory acceptance of malt beverage containing saponin compared to PGA containing ones. Less saponin content is suggested for flavored malt drinks. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05517-x.

6.
Food Chem ; 393: 133293, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653992

RESUMO

In the current study, the physicochemical and emulsifying properties of modified waxy maize starch obtained through a new environmentally friendly method of esterification were evaluated. The starch modification was carried out in NaOH solution with different levels of octanoyl, myristoyl, and stearoyl chlorides. Increasing the fatty acid chlorides concentration led to the degree of substitution increment, while reaction efficiency and yield decreased. Based on fourier transform infrared spectroscopy results, the presence of two new bands of carbonyl (1740-1750 cm-1) and carboxyl (1570 cm-1) groups in the ester bond confirmed the successful starch esterification process. The level of 0.1 mL fatty acid chlorides/g of starch demonstrated the highest emulsifying properties. Upon esterification, the crystalline structure of amylopectin was destroyed, indicating no gelatinization features. Therefore, using the fatty acid chlorides in an alkaline condition could be suggested as a feasible way to modify waxy maize starch toward hydrophobicity increment with desirable properties.


Assuntos
Amilopectina , Zea mays , Amilopectina/química , Cloretos , Esterificação , Ácidos Graxos , Amido/química , Zea mays/química
7.
Antioxidants (Basel) ; 12(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36670914

RESUMO

Husk powder was prepared from seven varieties of walnut fruit and their hulling rate, chemical compounds, and total phenolic contents were evaluated. The apolar and polar extracts were prepared, respectively, from hexane and a hydroethanolic solvent, while qualitative and semi-quantitative analyses were performed by GC/MS and UHPLC-PDA-HRMS/MS. The antioxidant, antimicrobial, and antitumor properties of green walnut husk were also evaluated. The total content of phenolic compounds varied between the varieties, ranging from 35.2 ± 0.9 to 58.0 ± 0.0 mg/g gallic acid equivalent of dry husk weight (dw). The apolar extract was found to contain alkanes, tocopherols, sterols, and fatty acids, including oleic, linoleic, and linolenic, while the polar extract showed the presence of phenolics including salicylate glucuronide, taxifolin, catechin, and quercetin isomers. The antioxidant power obtained by the PAOT (total antioxidant power) method for the husk powders ranged from 256.5 ± 5.9 to 746.8 ± 6.9 score/g dw, and seemed consistent with the total phenolic content and the results obtained by the classic antioxidant test with DPPH. The walnut husk also showed an antibacterial effect against Gram-negative and Gram-positive bacteria and cytotoxic potential against HepG2. Among the selected varieties, the green Saman had the highest antioxidant properties, while the Saman with a brown color had the lowest.

8.
J Food Sci ; 86(12): 5200-5212, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34773402

RESUMO

Detoxification of aflatoxin M1 from solution and milk using layered double hydroxides was investigated. The Aluminum-Magnesium layered double hydroxide (Al-Mg LDH) and Iron-Magnesium layered double hydroxide (Fe-Mg LDH) were selected in their calcined and non-calcined forms to evaluate the effect of the calcination on detoxification. These materials were produced using the co-precipitation method. Preliminary adsorption tests confirmed use of Al-Mg LDH as the selected adsorbent. Characteristics of the adopted adsorbent were studied and confirmed by XRD, FTIR, SEM, and BET methods. Effects of the initial content of aflatoxin, amount of the adsorbents and detoxification time were investigated. Influence of the adsorbents on the nutritional aspects of milk were also studied. The study showed that while the non-calcined forms of LDH were not able to adsorb aflatoxin M1 more than 23%, the calcined form of Al-Mg LDH exhibited 100% adsorption in the solutions and about 70-100% in the contaminated milk samples. The reason is pointed to the fact that calcination of Al-Mg LDH considerably increased the surface area, the total pore volume, and the pore size of the material. Multivariate regression analysis and calculation of the Pearson correlation factor showed that the remained aflatoxin at each time was more strongly correlated with the initial amount of aflatoxin and the elapsed time and less strongly with the amount of the adsorbent. It was found that the adsorption isotherms fitted to the Freundlich equation with a high adsorption capacity of 555.5 mg g-1. PRACTICAL APPLICATION: This study is focused on examining ability of layered double hydroxides (LDH) for adsorbing AFM1 . LDHs are promising layered materials due to some of their interesting characteristics, such as ease of synthesis and uniqueness of structure. In practice, results of this study can be used for detoxification of aflatoxin, especially in milk, at high efficiency in shorter time durations.


Assuntos
Aflatoxina M1 , Alumínio , Adsorção , Animais , Hidróxidos , Magnésio , Leite
9.
Food Sci Nutr ; 7(7): 2353-2360, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31367364

RESUMO

The objective here is to enrich orange juice through encapsulated lime by-product extract (LBE) through freeze-drying, in order to increase lime by-product consumption, in addition to increasing nutrition value of orange juice. The properties of both the LBE and microparticles are measured. The total polyphenolic compound (TPC) was measured to be 34.5 ± 0.5 (mg gallic acid/g LBE). The obtained value of encapsulation efficiency (EE) was within the 55%-70% range. The encapsulation method was satisfactory. The particle size is within 10-21 µm range, and differences between all treatments were statistically notable (p < 0.05). The lack of melting peaks in the thermal profiles by differential scanning calorimeter (DSC) of microparticles confirmed that hesperidin was well embedded in the polymeric cover. According to the sensory evaluations of orange juice which was enriched with LBE microparticles, the bitter taste was not perceived in some treatments.

10.
Int J Biol Macromol ; 118(Pt A): 1168-1173, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30001603

RESUMO

The asafoetida gum was extracted and purified from oleo-gum-resin of Ferula assa foetida root and characterized by high pressure anions exchange chromatography after acidic hydrolysis. It was composed of Gal:Ara:Rha:GlcA with the ratio 11.5:5.0:2.1:1.0. This monosaccharide composition was found similar to that of a commercial Arabic gum which exhibited a Gal:Ara:Rha:GlcA ratio of 11.7:5.4:3.2:1.0. As the Arabic gum is currently used for its emulsifying properties, the two gums were evaluated for their functional and rheological behaviors. Surface and interfacial tensions values were lower for asafoetida gum compared to Arabic gum. Critical micelle concentration was achieved at concentrations of 0.5% w/w and 1% w/w for asafoetida and Arabic gums, respectively. Values of emulsion capacity, emulsion stability and foaming properties were considerably higher for asafoetida gum in contrast to emulsion activity index that was lower than that of Arabic gum. As those of Arabic gum, solutions of asafoetida gum (2-30% w/w) exhibited Newtonian flow behavior at shear rates between 1 and 500 s-1. Apparent viscosities of Arabic and asafoetida gums were close and logically decreased by increasing temperature (10-80 °C). Higher viscosities were achieved at higher pH and CaCl2 concentrations.


Assuntos
Ferula/química , Gomas Vegetais/química , Emulsões , Micelas , Reologia , Viscosidade
11.
Int J Biol Macromol ; 118(Pt A): 1073-1081, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29964113

RESUMO

Sodium alginate from Nizimuddinia zanardini (an Iranian brown algae) was extracted with acid and alkaline solutions, partially and totally hydrolyzed and analyzed for its biochemical composition. 1H NMR spectroscopy, SEC-MALLS, HPAEC and FT-IR were performed to determine its structure and its physico-chemical properties. This alginate has a M/G ratio of 1.1, a molecular weight of 103 kDa, a polydispersity index of 1.22, and an intrinsic viscosity of 342 mL/g. Its antioxidant activity was tested by DPPH radical scavenging showing its potential for food preservation. Rheological properties of solutions of this alginate with concentrations between 1 and 5% (w/v) in water and 0.5 M NaCl were investigated indicating a Newtonian fluid type behaviour in water and a shear thinning fluid type behaviour in NaCl solutions.


Assuntos
Alginatos , Sequestradores de Radicais Livres/química , Phaeophyceae/química , Alga Marinha/química , Alginatos/química , Alginatos/isolamento & purificação , Ácido Glucurônico/química , Ácido Glucurônico/isolamento & purificação , Ácidos Hexurônicos/química , Ácidos Hexurônicos/isolamento & purificação , Irã (Geográfico)
12.
J Food Sci ; 83(7): 2008-2013, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29802731

RESUMO

Aflatoxin M1 (AFM1) contamination presents one of the most serious concerns in milk safety. In this study, the immobilization of Saccharomyces cerevisiae was used to detoxify AFM1-contaminated milk. The yeasts were immobilized on perlite for 24 and 48 hr, and the best immobilization time was achieved at 48 hr. Microscopic examination confirmed successful immobilization. The milk samples with 0.08, 0.13, 0.18, and 0.23 ppb AFM1 contamination were passed through the biofilter for 20, 40, and 80 min. The results showed a significant reduction in AFM1 concentration for all the milk samples with various initial AFM1 contents. The contaminated milk with 0.08 ppb AFM1 was completely cleared after 40 min of circulation while for the milk solution with 0.23 ppb, the highest AFM1 reduction was obtained at about 81.3% after 80 min circulation. In addition, the biofilter was saturated after the third step of milk circulation, containing 0.23 ppb AF, in which each step duration was 20 min. This study showed the excellent capability of the immobilized cells on the perlite beads to detoxify the AFM1-contaminated milk without any side effects on its physicochemical properties. PRACTICAL APPLICATION: The immobilization of Saccharomyces cerevisiae cells on perlite beads can be used to detoxify AFM1-contaminated milk. The perlite can provide a perfect support for immobilization. With respect to qualitative properties, 20 min, was suggested as the optimum time for milk decontamination. This study indicated that the detoxification of contaminated milk using immobilized S. cerevisiae cells on the perlite support did not affect the different properties of detoxified milk. This method can lead to a practical solution to address aflatoxin contamination in dairy products considered high-risk foods.


Assuntos
Aflatoxina M1/metabolismo , Descontaminação/métodos , Manipulação de Alimentos/métodos , Leite/química , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Óxido de Alumínio/química , Animais , Bovinos , Células Imobilizadas/química , Células Imobilizadas/metabolismo , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Leite/microbiologia , Dióxido de Silício/química
13.
Carbohydr Polym ; 188: 188-196, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29525156

RESUMO

Electrohydrodynamic technique (EHD) has lately received considerable attention as an important non-thermal method used for food processing. In this work the effect of EHD on physicochemical properties of cellulose extracted from bagasse was investigated. A three-step process was chosen to extract cellulose fibers, which was performed under a high voltage electric field at the beginning of each step. The cellulose fibers were then characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Thermogravimetric Analysis (TGA). The morphological evaluation revealed that the cellulose fibers have smaller diameter and larger length compared to the microcrystalline cellulose. Moreover, according to the XRD patterns and FTIR spectrum, EHD-treated fibers mainly showed an amorphous structure, and contained a low crystalline fraction. The amorphous structure of cellulose fibers was confirmed by TGA analysis which revealed the presence of higher proportion of amorphous cellulose fraction causes early onset of thermal decomposition.

14.
Carbohydr Polym ; 181: 426-432, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253992

RESUMO

The gum asafoetida, an oleo-gum-resin from root of Ferula assa foetida, was extracted through alcoholic procedure followed by water extraction and then biochemically characterized using colorimetric assays, Fourier infrared spectroscopy, gas chromatography coupled to mass spectrometry, and 1D and 2D nuclear magnetic resonance. The gum was mainly composed of carbohydrates (67.39% w/w) with a monosaccharide distribution of 11.5: 5.9: 2.3: 1 between Gal, Ara, Rha and GlcA (molar ratio) and proteins (arabinogalactan protein). The polysaccharide consisted of a (1→3)-ß-d-galactan backbone ramified predominantly from O-6 but also from O-4 and O-4,6. Side chains included terminal-α-l-Araf, terminal-α-l-Rhap, (1→3)-α-l-Araf, (1→5)-α-l-Araf, terminal-ß-d-Galp, ß-d-GlcA and traces of (1→4)-ß-d-GlcA. X-ray diffraction pattern showed a semi crystalline microstructure. Thermal behavior of the gum was evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) revealed temperatures below and upper 200°C as dominant regions of weight loss.


Assuntos
Ferula/química , Gomas Vegetais/química , Gomas Vegetais/isolamento & purificação , Temperatura , Aminoácidos/análise , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cátions , Glicosídeos/química , Metais/química , Peso Molecular , Monossacarídeos/análise , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Food Sci Nutr ; 5(4): 845-851, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28748072

RESUMO

Stevia is a natural, non-nutritive sweetener can replace sugar in your diet to control diabetes and aid in weight loss. Naanberenji, an Iranian traditional cookie, is a well-reputed confectionary containing high sucrose and calorie value, for this reason its consumption in healthy diet has been restricted. In this study, the effect of sucrose replacement by stevioside-maltodextrin mixture on physicochemical properties of Naanberenji was evaluated in four replacing levels including 25%, 50%, 75%, and 100%. Results of texture evaluation revealed that hardness increases due to adding stevioside-maltodextrin (p < .05). Color analysis also showed that browning index by adding more mixture reduced. Moreover, the results of sensory analysis showed that treatment containing 25% stevioside-maltodextrin was the most similar sample to control and 23.06% reduction in sugar consumption achieved in this level of replacement. Therefore, its physicochemical properties (peroxide, acidity, chemical compounds, and hardness) were measured. According to the results, calorie amount decreased by 7.27 %. While there was no significant difference in the acidity of the aforesaid sample, peroxide results exhibited significant differences. Analysis of Farinograph plot revealed more water binding in comparison to control sample.

16.
Recent Pat Food Nutr Agric ; 8(3): 175-182, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28088897

RESUMO

BACKGROUND: Species identification and authentication in meat products are important subjects for ensuring the health of consumers. The multiplex-PCR amplification and species- specific primer set were used for the identification of horse, donkey, pig and other ruminants in raw and processed meat products. METHODS: Oligonucleotid primers were designed and patented for amplification of species-specific mitochondrial DNA sequences of each species and samples were prepared from binary meat mixtures. RESULTS: The results showed that meat species were accurately determined in all combinations by multiplex-PCR, and the sensitivity of this method was 0.001 ng, rendering this technique open to and suitable for use in industrial meat products. It is concluded that more fraud is seen in lower percentage industrial meat products than in higher percentage ones. There was also more fraud found in processed products than in raw ones. CONCLUSION: This rapid and useful test is recommended for quality control firms for applying more rigorous controls over industrial meat products, for the benefit of target consumers.


Assuntos
Análise de Alimentos/métodos , Carne/normas , Reação em Cadeia da Polimerase Multiplex/veterinária , Religião , Animais , Equidae/genética , Carne/classificação , Reação em Cadeia da Polimerase Multiplex/métodos , Ruminantes/genética , Especificidade da Espécie , Suínos/genética
17.
J Sci Food Agric ; 97(1): 341-349, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27059005

RESUMO

BACKGROUND: The present study aims to investigate the advantageous effects of wet heating, BLG (ß-lactoglobulin)/Ang (Angum gum) ratio, and pH (normal pH of mixed BLG and Ang solutions, pHc > pH > pHΦ1 ) on the emulsifying properties of wet-heated ß-lactoglobulin-wild almond gum exudate (Amygdalus scoparia Spach) mixture over those of electrostatic counterparts. RESULTS: Covalent linkage of BLG-Ang conjugates was confirmed by SDS-PAGE and FTIR analysis. Emulsion activity (EA), emulsion stability (ES), and droplet size characteristics of emulsions were significantly (P < 0.05 and P < 0.01) affected by electrostatic/wet-heating, biopolymer ratio, pH, and their interactions. The electrostatic complexes with pHc > pH > pHΦ1 exhibited higher EA and ES values for all the biopolymer ratios investigated than their electrostatic counterparts with pH after mixing. However, these values for the wet-heated samples at pH after mixing were found to be higher than those of the samples subjected to heat treatment at pHc > pH > pHΦ1 . Based on the results obtained, it was concluded that E/1:2/3.80 and W/1:2/6.69 were the two complexes with finer droplet size distributions after preparation (26.72 ± 3.71 and 15.27 ± 1.01 µm, respectively) and after one week of storage at 4 °C (30.71 ± 1.57 and 28.79 ± 0.56 µm, respectively) than others. Apparent viscosities of electrostatic and wet-heated complexes and emulsions made with the complexes were measured. CONCLUSION: Protein-polysaccharide interactions can be used as an efficient way for producing novel emulsifiers/stabilisers after heat treatment. © 2016 Society of Chemical Industry.


Assuntos
Emulsificantes/química , Temperatura Alta , Lactoglobulinas/química , Gomas Vegetais/química , Prunus/química , Biopolímeros/química , Eletroforese em Gel de Poliacrilamida , Emulsões/química , Concentração de Íons de Hidrogênio , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Viscosidade
18.
Carbohydr Polym ; 157: 1620-1627, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-27987876

RESUMO

In this research, the improvement of emulsifying properties of chemically modified canola protein isolate (CPI) with gum Arabic (GA) through Maillard reaction under natural pH at 90°C was investigated. The stability, rheology and morphology of oil-in-water emulsions stabilized by conjugate of two biopolymers were evaluated by determination of droplet size, emulsifying activity (EAI), emulsifying stability (ESI) and creaming indices. The conjugate-stabilized emulsion showed smaller mean droplet size and lower creaming index values which were more effective to stabilize the emulsion compared to CPI and mixture of two biopolymers especially if pH was near the isoelectric point of CPI or when emulsions heated from 30 to 90°C. Moreover, our results demonstrated that EAI, ESI and viscosity of emulsion for CPI-GA conjugate were significantly more than those of CPI-GA mixture and CPI. These results suggested that Maillard reaction could be one of the most promising approaches to improve emulsifying properties of CPI for food applications.


Assuntos
Brassicaceae/química , Emulsificantes/química , Goma Arábica , Proteínas de Plantas/química , Emulsões , Glicosilação , Reação de Maillard
19.
Carbohydr Polym ; 155: 201-207, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27702505

RESUMO

The aim of this study was to produce covalently attached conjugate between canola protein isolate (CPI) and gum Arabic (GA) in aqueous solutions via the Maillard reaction at 90°C in a model system consisting of 2% CPI and 1, 2 or 4% GA. Upon decreasing of free amino group content in the glycosylated CPI to 72%, a new band near the loading end of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a shift of CPI peak in high performance size exclusion chromatography confirmed that the covalent attachment of CPI to GA was successful. The results of secondary structure analysis suggested that grafted CPI had decreased α-helix and ß-sheet levels and increased random coils level. The solubility of CPI at isoelectric point was improved remarkably after grafting with GA. The optimal conjugation conditions chosen from the further experiments were 1% of GA, 90°C and reaction time 15min.


Assuntos
Brassicaceae/química , Goma Arábica/química , Reação de Maillard , Proteínas de Plantas/química , Estrutura Secundária de Proteína , Solubilidade , Água
20.
Carbohydr Polym ; 141: 211-9, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-26877015

RESUMO

In this study, cellulose foams incorporated with surface-modified montmorillonite (SM-MMT) were prepared following NaOH dissolution and regeneration into water and ethanol. According to the SEM images, the type of coagulating agent significantly affected the morphological properties of composite foams. The crystalline parameters were evaluated using wide-angle X-ray diffraction (WAXD), which showed an increase in crystal size as the effect of SM-MMT; however, the crystal size decreased for the samples treated with ethanol. The distribution of hydrogen bond types was also investigated using Fourier transform infrared (FTIR). Resolving the hydrogen-bonded OH stretching band at around 3340 into five bands indicated that presence of SM-MMT caused the shift of OH-stretching vibration band to lower wave number due to new hydrogen bonds between cellulose and SM-MMT. In general, the results indicated a change in the contents of the intra- and inter-molecular hydrogen bonds when the coagulant was changed or SM-MMT was incorporated.


Assuntos
Bentonita/química , Celulose/análogos & derivados , Nanocompostos/química , Cristalização , Etanol/química , Polimerização , Água/química
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