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1.
Heliyon ; 9(9): e19677, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809870

RESUMO

The surface activity of γ-oryzanol was evaluated by the pendant drop method (PDM), and its self-stabilizing properties were investigated by high-pressure homogenization (HPH) and solvent displacement method (SDM). Emulsions prepared by HPH were highly unstable due to the poor surface-active character of γ-oryzanol as identified by the PDM. In contrast, solid dispersions fabricated by SDM had comparable particle size to those prepared using Tween 80 (T80) as surfactant, and were stable up to 30 days of storage at 4 °C. The self-stabilizing properties of γ-oryzanol were attributed to the mechanism of spontaneous particle formation in SDM and to the ability of γ-oryzanol molecules to prevent particles aggregation by electrostatic repulsion. The outcome of this study indicates the potential of encapsulating selected bioactive compounds, such as γ-oryzanol, in stable colloidal systems by SDM without adding emulsifier(s), regardless of their surface-active character.

2.
Foods ; 12(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37048242

RESUMO

This study aimed to improve the visual aspects and chemical, techno-functional and rheological characteristics of Gryllus bimaculatus cricket powder through the use of different solvents, with the objective of using it as a protein source in food production. Four treatments (pH 5 aqueous solution, ethanol 20%, ethanol 99.5%, and hexane) were applied to the powder, and analyses were conducted to assess changes in the previously mentioned parameters. The results showed that the treatments led to an increase in protein concentration (from 55.4 to 72.5%) and a decrease in fat concentration (from 33.0 to 6.8%) in ethanol 99.5% treated powder, as well as a reduction in anti-nutritional compounds concentration, such as tannins (from 13.3 to 5.9 g/kg), in pH 5 treated powder, which is important for the nutritional value of the final product. The color of the powders was improved, being lighter after hexane and ethanol 99.5% treatments due to the removal of melanin with the defatting process. Flowability, water, and oil holding capacity were also improved in the defatted powders. All the results suggest that the main composition of the powder directly influences the analyzed parameters. These findings suggest that cricket powder treated with solvents can be used as a protein source in different food applications.

3.
Polymers (Basel) ; 15(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36679351

RESUMO

The present study aimed to investigate the physical stability in terms of (droplet size, pH, and ionic strength) and chemical stability in terms of (retention) of D-limonene (LM) in the nanoemulsions after emulsification as well as after storing them for 30 days under different temperatures (5 °C, 25 °C, and 50 °C). LM is a cyclic monoterpene and a major component extracted from citrus fruits. The modification of disperse phase with soybean oil (SB) and a nonionic emulsifier (Tween 80) was adequate to prepare stable LM-loaded nanoemulsions. LM blended with SB-loaded nanoemulsions were stable against droplet growth over pH (3-9) and ionic strength (0-500 mM NaCl). Regarding long-term storage, the prepared nanoemulsions demonstrated excellent physical stability with droplet size ranging from 120-130 nm during 30 days of storage at both 5 °C and 25 °C; however, oiling off started in the emulsions, which were stored at 50 °C from day 10. On the other hand, the retention of LM in the emulsions was significantly impacted by storage temperature. Nanoemulsions stored at 5 °C had the highest retention of 91%, while nanoemulsions stored at 25 °C had the lowest retention of 82%.

4.
Polymers (Basel) ; 14(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36236052

RESUMO

The plastic waste problem has recently attracted unprecedented attention globally. To reduce the adverse eff ects on environments, biodegradable polymers have been studied to solve the problems. Poly(ε-caprolactone) (PCL) is one of the common biodegradable plastics used on its own or blended with natural polymers because of its excellent properties after blending. However, PCL and natural polymers are difficult to blend due to the polymers' properties. Grafted polymerization of maleic anhydride and dibenzoyl peroxide (DBPO) with PCL is one of the improvements used for blending immiscible polymers. In this study, we first focused on the effects of three factors (stirring time, maleic anhydride (MA) amount and benzoyl peroxide amount) on the grafting ratio with a maximum value of 4.16% when applying 3.000 g MA and 1.120 g DBPO to 3.375 g PCL with a stirring time of 18 h. After that, the grafting condition was studied based on the kinetic thermal decomposition and activation energy by the Coats-Redfern method. The optimal fitting model was confirmed by the determination coefficient of nearly 1 to explain the contracting volume mechanism of synthesized PCL-g-MA. Consequently, grafted MA hydrophilically augmented PCL as the reduced contact angle of water suggests, facilitating the creation of a plastic-biomaterial composite.

5.
J Food Sci Technol ; 59(11): 4427-4435, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36193465

RESUMO

In this study, we evaluated the caprylic acid-based oil-in-water (O/W) emulsion-assisted extraction of lycopene from tomatoes. Emulsion-assisted extraction was performed using two types of micron-sized O/W emulsions: (a) O/W emulsion with absence or (b) presence of 0.1% (w/w) of Tween 20 emulsifier. This green extraction technique was compared with the conventional method using soybean oil, tributyrin, and caprylic acid. The results show that caprylic acid, a green solvent, is significantly more effective for lycopene recovery than soybean oil and tributyrin. In the absence of an emulsifier, caprylic acid-based O/W emulsion significantly improved the lycopene content by 14.69 mg/g, corresponding to a 98.59% extraction efficiency at 50 ˚C. The capability of the proposed approach to lycopene recovery was explained in terms of lycopene affinity, the ability to swell the tomato cell, and some other standard parameters. In addition, caprylic acid has the significant advantage that once developed with the extracted lycopene can be used directly as a food additive.

6.
Front Nutr ; 9: 822053, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711552

RESUMO

Although natural emulsifiers often have many drawbacks when used alone, their emulsifying ability and stability can usually be improved unexpectedly when used in combination. In this study, monodisperse emulsions stabilized by combining two natural protein emulsifiers, i.e., whey protein isolate (WPI) and sodium caseinate (SC), in different proportions were prepared using microchannel (MC) emulsification. The influences of temperature, pH, ionic strength, and storage time on the microstructure and stability of the emulsions were examined. Analysis of the microstructure and droplet size distribution revealed that the WPI-, SC-, and mixed protein-stabilized emulsions exhibited uniform droplet distribution. The droplet size and ξ-potential of the MC emulsions stabilized by mixed protein emulsifiers were higher than those of the emulsions stabilized by WPI or SC separately. The emulsions stabilized by the two types of proteins and mixed emulsifiers had better stability under high salt concentrations than the synthetic emulsifier Tween 20. WPI-SC-stabilized emulsions were more resistant to high temperatures (70-90°C) and exhibited excellent stabilization than those stabilized by WPI and SC, which was attributed to the more sufficient coverage provided by the two types of protein emulsifier layers and better protein adsorption at the oil-water interface. These results indicate that WPI-SC is a potential stabilizer for MC emulsion requirements. This study provides a basis for the formulation of monodisperse and stable natural emulsion systems.

7.
Food Res Int ; 153: 110894, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35227489

RESUMO

Alpha-terpineol (α-TOH) is a promising monoterpenoid detaining several biological activities. However, as a volatile molecule, the incorporation of α-TOH within formulated products poses several challenges related to its stability. In this sense, nanoencapsulation works as a key technology to protect the bioactivity of low molecular weight oils, like α-TOH, against environmental stresses (heat, light, and moisture), mitigating their susceptibility to degradation (oxidation and volatilization). Physical properties of encapsulated flavor/essential oil have been extensively reported, whereas there is a lack in the literature regarding their chemical stability, which is usually the main purpose of encapsulation. Thus, in this study, the physicochemical stability of the formulated oil-in-water nanoemulsion loaded with α-TOH stabilized with Quillaja saponins (QSs) as a natural emulsifier (α-TOH-QSs-NE) were tracked in a long-term (up to 280th day). Along with time, mean droplet diameter (MDD) and turbidity were used as a reference for physical parameters; while the chemical stability was monitored using gas chromatography analysis to quantify the mark content of α-TOH into the NE. Results indicated that α-TOH-QSs-NE was successfully formulated with a high-load amount of α-TOH (90 mg mL-1). α-TOH-QSs-NE showed great physicochemical stability regardless the storage-temperature (5 °C or 25 °C) up to 280th day, with no significant alterations in the MDD or turbidity, where c.a. 79% of the initial amount of the nanoemulsified α-TOH remained detectable in α-TOH-QSs-NEs, with no finding of degradation products. Thus, the data here disclosure may be useful for innovative application of α-TOH in foodstuffs.


Assuntos
Óleos , Água , Monoterpenos Cicloexânicos , Emulsões/química , Óleos/química , Saponinas de Quilaia/química , Água/química
8.
Foods ; 10(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34945700

RESUMO

Nanoencapsulation is an attractive technique used for incorporating essential oils in foods. Thus, our main goal was to formulate a novel nanoemulsion (NE) with nanoscale droplet size and lowest interfacial tension in the oil-water interface, contributing positively to the stability and the enhancement of essential oil potential. Thereby, response surface methodology (RSM), with mixture design was used to optimize the composition of the NE lipid phase. The essential oil combinations were encapsulated through high-pressure homogenization (HPH) with the binary emulsifier system (Tween 80: Gum Arabic). Then, the electrophoretic and physical properties were evaluated. We also conducted a follow-up stability and antimicrobial study that examined the stabilization mechanism of optimal NE. Thereafter, the effect of nanoencapsulation on the essential oil composition was assessed. The RSM results were best fitted into polynomial models with regression coefficient values of more than 0.95. The optimal NE showed a nanometer-sized droplet (270 nm) and lower interfacial tension (~11 mN/m), favoring negative ζ-potential (-15 mV), showing good stability under different conditions-it synergistically enhances the antimicrobial potential. GC-MS analysis showed that the use of HPH affected the active compounds, consistent with the differences in linalool and 2-Caren-10-al content. Hence, the novel nanometric delivery system contributes to food industry fortification.

9.
NPJ Sci Food ; 5(1): 31, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34782642

RESUMO

In this study, the interfacial ability of α-terpineol (α-TOH) was reported, followed by its trapping into oil-in-water (O/W) nanoemulsion as active-ingredient and the long-term observation of this nanosystem influenced by the storage-time (410-days) and temperature (5, 25, 50 °C). The results indicated that the α-TOH can reduce the interfacial tension on the liquid-liquid interface (ΔG°m = -1.81 KJ mol-1; surface density = 8.19 × 10-6 mol m-2; polar head group area = 20.29 Å2), in the absence or presence of surfactant. The O/W nanoemulsion loaded with a high amount of α-TOH (90 mg mL-1; 9α-TOH-NE) into the oil phase was successfully formulated. Among the physical parameters, the mean droplet diameter (MDD) showed a great thermal dependence influenced by the storage-temperature, where the Ostwald ripening (OR) was identified as the main destabilizing phenomena that was taking place on 9α-TOH-NE at 5 and 25 °C along with time. Despite of the physical instability, the integrity of both nanoemulsion at 5 °C and 25 °C was fully preserved up to 410th day, displaying a homogeneous and comparable appearance by visual observation. On contrary, a non-thermal dependence was found for chemical stability, where over 88% of the initial amount of the α-TOH nanoemulsified remained in both 9α-TOH-NE at 5 and 25 °C, up to 410th day. Beyond the key data reported for α-TOH, the importance of this research relies on the long-term tracking of a nanostructured system which can be useful for scientific community as a model for a robust evaluation of nanoemulsion loaded with flavor oils.

10.
J Food Sci Technol ; 58(9): 3314-3327, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34366449

RESUMO

Foodborne diseases are a huge problem that causes dramatic economic losses and threatens consumers' lives. Chitosan-based film incorporated with essential oil nanoemulsion would be an ideal solution to build smart food packaging. Thyme oil was formulated into nanoemulsion and checked for the droplet size, distribution, and physical stability. The prepared thyme oil nanoemulsion was incorporated with the chitosan-filmogenic mixture through continuous mixing. The filmogenic mixture was cast, dried, and assessed for their morphological, physical, mechanical, and molecular properties. In addition to investigating the antimicrobial activity against gram-negative (Escherichia coli spp.) and gram-positive (Bacillus subtilis spp.) bacteria. Thyme oil nanoemulsion showed a small droplet size (89-90 nm) with considerable stability. Incorporating thyme oil nanoemulsion with the chitosan-based film did not cause great change in the film appearance and transparency, while enhanced the light barrier property. It caused noticeable changes to the film physical (ex., moisture content, water vapor permeability, among others) and mechanical (Tensile strength and elongation at break) properties. On the other hand, it improved the film thermal stability without causing a structural alteration in the film matrix. Incorporation of chitosan-based film with thyme nanoemulsion remarkably improved the antimicrobial activity against foodborne pathogens. Chitosan-based film incorporated with thyme oil nanoemulsion would be considered a promising antimicrobial food packaging material with considerable packaging properties, and substantial growth inhibitor of foodborne pathogens.

11.
Food Chem ; 359: 129963, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951609

RESUMO

This research studies the application of a specific nanoemulsion as anti-Escherichia coli agent. The specific mixture was generated by a simplex-centroid design. Physicochemical parameters such as droplet average diameter, pH, viscosity, density, turbidity, whitening index, refractive index, stability (thermal, physical, and osmotic stability), and antibacterial activity kinetic, have been assessed. The mixture nanoemulsions had droplet diameters significantly smaller than those of clove or cinnamon nanoemulsions. Individual and mixture essential oils nanoemulsion exhibited appropriate stability under pH, thermal, and ionic stress as well as after mid-term storage. Antibacterial activity kinetic revealed the fast and pronounced efficacy of mixture nanoemulsions on E. coli (reach 98% of growth inhibition), especially for the nanoemulsion composed of 50% essential oil in the dispersed phase upon 20 days of storage. All data considered, the actual work evidences the promising advantages of using specific nanoemulsions as delivery systems of antibacterial agents in the beverage and food industry.


Assuntos
Anti-Infecciosos/farmacologia , Cinnamomum zeylanicum/química , Emulsões/química , Escherichia coli/efeitos dos fármacos , Lavandula/química , Óleos Voláteis/química , Syzygium/química , Óleos Voláteis/farmacologia
12.
Food Chem ; 337: 127949, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919267

RESUMO

This study compared the interfacial and emulsifying properties of purified saponins and non-purified saponin-rich extracts of Glycyrrhiza glabra, and highlighted potential mechanisms by which crude surface-active compositions, such as liquorice root extract (LRE), act as emulsifiers. LRE presented different fluid properties, in comparison to purified glycyrrhizin (PG), at equivalent glycyrrhizin concentrations. Particularly, it exhibited limited glycyrrhizin fibrilization at pH < pKa and efficiently reduced the interfacial tension at the soybean oil/water interface, independently of pH. LRE also presented better emulsification properties, in comparison to PG samples. Emulsions prepared using LRE had lower droplet sizes when using higher oil mass fractions or lower homogenization pressures, which was attributed to 2 main factors: (i) efficient adsorption of glycyrrhizin molecules at relatively low interfacial curvatures, thus accelerating oil phase breakup during homogenization and (ii) sufficient coverage of newly generated droplets due to adsorption of residual surface-active components (e.g. proteins), thus minimizing droplet coalescence.


Assuntos
Emulsificantes/química , Ácido Glicirrízico/química , Extratos Vegetais/química , Emulsões/química , Glycyrrhiza/química , Saponinas/química , Óleo de Soja/química , Tensão Superficial , Água/química
13.
Carbohydr Polym ; 251: 116990, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142562

RESUMO

Microfibrillated cellulose (MFC) from Argan (Argania spinosa) shells was prepared by chemical purification of cellulose, then mechanical disintegration via high pressure homogenization was performed to isolate fibrils of cellulose. Chemical characterization of raw argan shell (AS-R), purified cellulose (AS-C), and argan shell MFC (AS-MFC) included FT-IR, XRD and NMR. Morphological characterization of AS-MFC was assessed using TEM. Next, the use of AS-MFC as oil-in-water (O/W) emulsions stabilizer was investigated. The particle concentration was observed to affect the long-term stability of the emulsions; high concentrations (0.5-1 % w/w) of AS-MFC resulted in emulsions that were thermodynamically stable during 15 days of storage, which was demonstrated by the droplet's size evolution. The suitable oil concentration for a maximum volume of emulsion using 1 % w/w AS-MFC was demonstrated. The results show that AS-MFC is able to stabilize 70 % w/w MCT oil without visual phase separation. Finally, CLSM shows the adsorption of AS-MFC at the oil-water interface and the formation of a 3D network surrounding oil droplets, confirming Pickering emulsion formation and stabilization.


Assuntos
Celulose/química , Sapotaceae/química , Eletrólitos , Emulsões , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Nanofibras/química , Nanofibras/ultraestrutura , Tamanho da Partícula , Óleos de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Difração de Raios X
14.
Food Res Int ; 137: 109723, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233292

RESUMO

In this study, the effect of spraying method as an application technique for xanthan gum-based edible coatings was investigated, based on its barrier and microbial properties on fresh-cut lotus root. Xanthan gum solutions (0.1%, 0.3%, and 0.5%) were prepared and incorporated with 2% (w/w) citric acid as an anti-browning agent and 1% (w/w) glycerol as plasticizer. The coatings were then sprayed using a pilot spray system to 5 mm-thick slices of fresh-cut lotus root for 20 s, packed in polyethylene bags, stored for 16 d at 5 °C and analyzed for color, pH, morphology and microbial counts. It was found that spray-coated fresh-cut lotus root samples had significant reduction in the total color changes as compared to non-coated samples. The experimental results suggested that the spray coating treatments were effective in decreasing the enzymatic browning of fresh-cut lotus root during storage which could potentially increase its shelf-life in the market. In addition, we have also found that the xanthan gum-based spray coated treatments were also effective against inhibiting the growth of Bacillus subtilis during 24 h of incubation which were indicated by the lower microbial counts recorded as compared to non-coated fresh-cut lotus root samples. In this part of the work, the author highlighted the spray coating technique of xanthan gum-based edible coatings as a promising strategy in improving the storage stability of fresh-cut lotus root during post-harvest storage. Overall, the application of edible coatings is a promising strategy in extending the shelf life of fresh-cut lotus root. In the future, the author aims to widen the scope of the application of these coatings to other agricultural products which are prone to degradation during storage in the market.


Assuntos
Filmes Comestíveis , Nelumbo , Polissacarídeos Bacterianos , Tecnologia
15.
ACS Omega ; 4(6): 10502-10509, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31460147

RESUMO

The effect of natural emulsifiers (whey protein isolate, WPI; modified lecithin, ML; and gum arabic, GA) on the formulation, stability, and bioaccessibility of fucoxanthin-loaded oil-in-water (O/W) emulsions was determined in this study. The fine emulsions were prepared under high-pressure homogenization at 100 MPa for 4 passes, using 2 wt % WPI, ML, and GA, resulting in emulsions with the droplet sizes of 136, 140, and 897 nm, respectively. The chemical stability of fucoxanthin in the emulsions after long-term storage at ambient temperature decreased in the following order: WPI > GA > ML. The release of free fatty acids of fucoxanthin, studied by in vitro digestion, decreased in the following order: WPI > ML > GA > bulk oil. The bioaccessibility of fucoxanthin in emulsions stabilized by WPI, ML, and GA after in vitro digestion were 92.5 ± 6.8%, 44.6 ± 0.4, and 36.8 ± 2.5, respectively. These results indicate that natural emulsifier type and concentration used significantly affects the formulation, stability, lipid digestion, and fucoxanthin bioaccessibility, which may be ascribed to the different properties of each emulsifier. The bioaccessibility of fucoxanthin was improved by using emulsion-based delivery systems.

16.
Food Res Int ; 116: 953-962, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30717028

RESUMO

Apigenin has attracted a great interest in the food industry due to the wide range of its biological activities including antioxidant and anti-inflammatory. The encapsulation of apigenin in oil-in-water (O/W) emulsions could overcome its low solubility and lead to the development of new functional food products. The aim of this study is to formulate food-grade O/W submicron emulsions loaded with apigenin using high-pressure homogenization. Supersaturated solutions of 0.1 wt% apigenin in ethyl oleate were heated at 100 °C for 30, 60, or 120 min and the supernant after centrifugation were used as to-be-dispersed phases. An aqueous solution containing 1 wt% tween 20 was used as the continuous phase. We examined the effect of heating process of the ethyl oleate prior to emulsification and the homogenization-pressure (60-150 MPa) on the physico-chemical characteristics of the O/W emulsions immediately after formulation and during storage. Submicron O/W emulsions were formulated and the lowest average droplet diameter (dav) was 169 ±â€¯2.082 nm with a polydispersity index (PDI) of 0.06 ±â€¯0.002. After 30 days of storage at 4 °C, the O/W emulsion formulated remained physically stable with little change in their dav and PDI values. The preheat treatment of ethyl oleate, affected the initial loaded apigenin concentration but hardly affected the physico-chemical stability of O/W emulsions. However, HPLC analysis demonstrated that the emulsification pressure was a relevant parameter affecting apigenin retention during the storage of O/W emulsions. Apigenin degradation in ethyl oleate O/W emulsions followed zero order kinetics and about 91.5-93.5% of apigenin could be retained in O/W emulsions after 30 days of storage.


Assuntos
Apigenina/química , Manipulação de Alimentos/métodos , Alimento Funcional , Óleos/química , Ácidos Oleicos/química , Água/química , Emulsões , Temperatura Alta , Cinética , Tamanho da Partícula , Pressão , Solubilidade , Tensão Superficial , Viscosidade
17.
Food Chem ; 261: 322-328, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29739600

RESUMO

The formulation, physicochemical stability and bioaccessibility of astaxanthin (AST) loaded oil-in-water nanoemulsions fabricated using gypenosides (GPs) as natural emulsifiers was investigated and compared with a synthetic emulsifier (Tween 20) that is commonly applied in food industry. GPs were capable of producing nanoemulsions with a small volume mean diameter (d4,3 = 125 ±â€¯2 nm), which was similar to those prepared using Tween 20 (d4,3 = 145 ±â€¯6 nm) under the same high-pressure homogenization conditions. GPs-stabilized nanoemulsions were stable against droplet growth over a range of pH (6-8) and thermal treatments (60-120 °C). Conversely, instability occurred under acidic (pH 3-5) and high ionic strength (25-100 mM CaCl2) conditions. In comparison with Tween 20, GPs were more effective at inhibiting AST from degradation during 30 days of storage at both 5 and 25 °C. However, GPs led to lower lipid digestion and AST bioaccessibility from nanoemulsions than did Tween 20.


Assuntos
Emulsificantes/química , Emulsões/química , Gynostemma/química , Cinética , Concentração Osmolar , Extratos Vegetais/química , Polissorbatos/química , Xantofilas/química
18.
Food Res Int ; 106: 542-548, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579959

RESUMO

Açaí berry is the fruit of an Amazonian palm tree and rich in anthocyanins (ACNs). Scientific studies have proven the health benefits of açaí berry and declared this fruit as "super fruit". ACNs have high antioxidant activities, but they are unstable and can easily deteriorate during food processing. In order to protect ACNs and increase their applicability, food-grade water-in-oil (W/O) emulsions were successfully formulated with different concentrations of açaí berry extracts (AEs). The formulated W/O nanoemulsions were relatively stable, with no phase separation after 30 days of storage. The average droplet size varied between 146.8 and 814.8 nm, with higher values corresponding to samples without AEs. All W/O nanoemulsion samples exhibited antioxidant activity and high retention rates of polyphenols after 30 days of storage. ACN retention followed first-order kinetics, with high protection of ACNs observed in emulsified samples. 2% AE encapsulated in a 30 wt% W/O nanoemulsion had an estimated half-life of 385 days. The results indicate that stable nanoemulsion systems with high ACN protection can be produced with possible applications in the food and pharmaceutical industries.


Assuntos
Antocianinas/química , Antioxidantes/química , Euterpe/química , Manipulação de Alimentos/métodos , Frutas/química , Nanopartículas , Óleos/química , Água/química , Antocianinas/isolamento & purificação , Antioxidantes/isolamento & purificação , Emulsões , Armazenamento de Alimentos , Meia-Vida , Cinética , Nanotecnologia , Tamanho da Partícula
19.
Food Chem ; 255: 67-74, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29571499

RESUMO

In this study ginseng saponins (GS) were used as natural emulsifiers to formulate and stabilize O/W nanoemulsions loaded with astaxanthin (AST). GS were found to be highly effective at reducing the interfacial tension at the soybean oil-water interfaces, and were capable of producing nano-scaled droplets (d4,3 ≈ 125 nm) using a high-pressure homogenizer. The droplet size of the nanoemulsions decreased with increasing emulsifier concentration and homogenization pressure. The nanoemulsions were stable without droplet coalescence against thermal treatment (30-90 °C, 30 min), and over a narrow range of pH values (7-9). GS-coated droplets were unstable in acidic conditions (pH 3-6) and in the presence of salt (>25 mM NaCl). The formulated nanoemulsions showed slight change in d4,3 during 15 days of storage at 5, 25 and 40 °C. However, the chemical stability strongly depended on the storage temperature, with the lowest level of AST retained in nanoemulsions stored at higher temperature.


Assuntos
Emulsificantes/química , Emulsões/química , Nanotecnologia/métodos , Panax/química , Saponinas/química , Suplementos Nutricionais/análise , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Óleo de Soja , Tensão Superficial , Temperatura , Água , Xantofilas/análise
20.
Food Chem ; 246: 457-463, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29291873

RESUMO

In this study, we formulated and stabilized oil-in-water nanoemulsions using a crude extract from argan press-cake as sole emulsifier. Various extracts from argan press-cake were prepared in order to select the most surface-active one(s) foreseeing emulsions preparation. Fifty percent (v/v) ethanolic extract reduced the interfacial tension to a minimum value at both MCT oil and soybean oil interfaces (12.7 and 10.5 mN m-1 respectively). This extract was also effective at producing fine emulsions with small droplet sizes (d3,2 < 115 nm) and good physical stability using different oils such as soybean oil, MCT oil and fish oil and at conventional homogenization conditions (100 MPa for 4 passes). On the other hand, the emulsions were very sensitive to NaCl addition (≥25 mM) and to acidic pH (<3) indicating that the main stabilization mechanism is electrostatic, likely due to the presence of surface-active compounds with ionizable groups such as saponins.


Assuntos
Emulsões/química , Óleos de Plantas/química , Emulsificantes/química , Óleos de Peixe/química , Nanoestruturas/química , Saponinas/química , Cloreto de Sódio/química , Óleo de Soja/química , Tensão Superficial , Água/química
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