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1.
J Sci Food Agric ; 104(5): 3080-3089, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38063380

RESUMO

BACKGROUND: Okara is a by-product from the soybean industry and an abundant resource of insoluble soybean fiber (ISF). ISF with various properties could be obtained by different extraction methods. It is an attractive option to utilize okara by taking advantage of ISF as an emulsifier or stabilizer. RESULTS: Compared with the untreated ISF (ISFUT ), superfine grinding reduced the particle size and viscosity of ISF (ISFSG ). Steam explosion increased the water solubility from 17.5% to 51.7% but decreased the water holding capacity and swelling capacity of ISF (ISFSE ) from 15.0 and 14.0 g/g to 4.2 and 3.3 g/g, respectively. Emulsions prepared by ISFUT and ISFSG before or after enzymatic hydrolysis presented large oil droplets and were unstable. Although emulsions prepared by ISFSE after enzymatic hydrolysis (ISFSE-E ) showed flocculation, the volume-weighted average diameter (19.7 µm) were the smallest while the viscosity and viscoelastic modulus were the highest, and exhibited excellent physical stability during storage. CONCLUSION: ISF obtained by physical and hydrolysis treatment displayed diverging physicochemical properties while ISF prepared by steam explosion-enzymatic hydrolysis presented the best potential to stabilize emulsions. The present study could provide novel information about the utilization of okara by the application of ISF as an emulsifier or stabilizer. © 2023 Society of Chemical Industry.


Assuntos
Glycine max , Vapor , Emulsões/química , Hidrólise , Emulsificantes/química , Excipientes , Tamanho da Partícula , Água/química
2.
Soft Matter ; 19(22): 4062-4072, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37227429

RESUMO

Emulsion gels as soft materials were formulated by insoluble soybean fiber (ISF) assembled from okara in this study. Steam explosion on okara (ISFS) transformed the insoluble fiber in the original okara (ISFU) into soluble fiber. Enzymatic hydrolysis led to a lower protein content, smaller particle size and smaller contact angle of ISF. ISFE, which was obtained by enzymatic hydrolysis of ISFU, was not able to produce stable emulsion gels at 0.50 to 1.50 wt% ISF, whereas the ISF after a combined steam explosion-enzymatic hydrolysis treatment (giving rise to ISFSE) stabilized emulsion gels at varying oil volume fractions (φ) from 10 to 50%. The ζ-potential of emulsion gels was around -19 to -26 mV. The droplet size first decreased (from 43.8 µm to 14.8 µm when at φ = 0.3) with increasing ISF content (from 0.25 wt% to 1.25 wt%) and then remained constant, as also seen from the microstructure. The apparent viscosity and viscoelastic properties were strengthened upon increasing both the ISF concentration and oil volume fraction. The protein and soluble fiber contributed to the interfacial activity of ISF while the insoluble fiber played an important role in the gel-like structured network of emulsion gels, making them maintain physical stability during long term storage. These findings could provide novel information about soybean fiber to fabricate soft materials and the utilization of okara at an industrial-scale.


Assuntos
Glycine max , Vapor , Emulsões/química , Tamanho da Partícula , Géis/química
3.
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.

4.
J Sci Food Agric ; 103(14): 6920-6928, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37300816

RESUMO

BACKGROUND: Concentrated emulsions have been formulated in many foods. The insoluble soybean fiber (ISF) can be utilized as a particle to stabilize concentrated emulsions. However, the approach to control the rheological properties and stability of the ISF concentrated emulsions is still worth investigating. RESULTS: In this study, alkali-extracted ISF was hydrated by adding sodium chloride or heating and the prepared concentrated emulsions were subjected to freeze-thawing. Compared with the original hydration method, salinization reduced the absolute ζ-potential of the ISF dispersions to 6 mV, resulting in a lower absolute ζ-potential of the concentrated emulsions, which led to a decreased electrostatic repulsion and the largest droplet size, but to the lowest apparent viscosity, viscoelastic modulus, and stability. By contrast, hydration by heating promoted the interparticle interactions, and then a decreased droplet size (54.5 µm) but with a more densely distributed droplets was observed, together with enhanced viscosity and viscoelasticity properties. The fortified network structure improved the stability of the concentrated emulsions both against high-speed centrifugation and long-term storage. Additionally, secondary emulsification after freeze-thaw further improved the performance of the concentrated emulsions. CONCLUSION: The results suggest that the formation and stability of the concentrated emulsion could be regulated by different hydration methods of particles, which could be adjusted according to the practical applications. © 2023 Society of Chemical Industry.


Assuntos
Glycine max , Cloreto de Sódio , Emulsões/química , Fenômenos Químicos , Congelamento , Tamanho da Partícula
5.
Compr Rev Food Sci Food Saf ; 22(6): 4282-4301, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37583303

RESUMO

Polyglycerol polyricinoleate (PGPR) is a synthetic food additive containing a complex mixture of various esters. In recent years, there has been a growing trend to use PGPR-stabilized water-in-oil (W/O) emulsions to replace fat in order to produce low-calorie food products. In this respect, it is essential to comprehensively characterize the PGPR molecular species composition, which might enable to reduce its required amount in emulsions and foods based on a better understanding of the structure-activity relationship. This review presents the recent research progress on the characterization and quantitative analysis of PGPR. The influencing factors of the emulsifying ability of PGPR in W/O emulsions are further illustrated to provide new insights on the total or partial replacement of PGPR. Moreover, the latest progress on applications of PGPR in food products is described. Current studies have revealed the complex structure of PGPR. Besides, recent research has focused on the quantitative determination of the composition of PGPR and the quantification of the PGPR concentration in foods. However, research on the quantitative determination of the (poly)glycerol composition of PGPR and of the individual molecular species present in PGPR is still limited. Some natural water- or oil-soluble surfactants (e.g., proteins or lecithin) have been proven to enable the partial replacement of PGPR in W/O emulsions. Additionally, water-dispersible phytosterol particles and lecithin have been successfully used as a substitute of PGPR to create stable W/O emulsions.


Assuntos
Glicerol , Lecitinas , Glicerol/química , Ácidos Ricinoleicos/química , Emulsões/química , Água/química
6.
Magn Reson Chem ; 60(7): 659-670, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35037312

RESUMO

Fat crystallisation in emulsions is a complex process. One of the important parameters is the solid fat content (SFC). Up to now, there is no standardised method to measure the SFC in emulsions, let alone to determine the SFC of the fat inside droplets, thus avoiding the signal of the aqueous phase. This work evaluates the capabilities of deconvolution of the free induction decay (FID)-Carr-Purcell-Meiboom-Gill (CPMG) signal of emulsions. Three models were evaluated. The first model was a combination of a Gaussian function and a bi-exponential function (GBE model). The second model combined a Gaussian function with multiple exponential functions (GME model). The last model contained multiple Gaussian functions and multiple exponential functions (MGME model). The latter two models used a simplified CONTIN analysis. Based on the analysis of the determination coefficient R2 , the calculated water content and the estimated SFC of nonemulsified two-phase systems, the GBE model was selected to analyse the FID-CPMG signal of emulsified systems. However, the results obtained with the other models did not differ substantially, and hence, they could be used to obtain a full relaxation time distribution. When the GBE model was applied on different emulsion systems, no significant differences in estimated SFC of the fat phase were found, thus indicating that the emulsion formulation (i.e. water-in-oil [W/O], oil-in-water [O/W] or water-in-oil-in-water [W/O/W]) only had a minor effect on the SFC in the systems considered here.


Assuntos
Brânquias , Água , Animais , Emulsões/química , Espectroscopia de Ressonância Magnética , Água/química
7.
Molecules ; 27(2)2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35056714

RESUMO

The permeation of amino acids and di-peptides with different hydrophobicities across the oil phase in W/O/W double emulsions was investigated at different concentrations, considering the pH of the aqueous phase. Moreover, the particle size, yield of entrapped water and release kinetics of the double emulsions was evaluated as a function of time. Regarding the release of the entrapped amino acids and di-peptides, their hydrophobicity and the pH had a significant effect, whereas the concentration of the dissolved compound did not lead to different release kinetics. The release of the amino acids and di-peptides was faster at neutral pH as compared to acidic pH values due to the increased solute solubility in the oil phase for more hydrophobic molecules at neutral pH. Regarding the effect of the type of oil, much faster amino acid transport was observed through MCT oil as compared to LCT oil, which might be due to its higher solubility and/or higher diffusivity. As di-peptides released faster than amino acids, it follows that the increased solubility overruled the effect from the decreased diffusion coefficient of the dissolved compound in the oil phase.


Assuntos
Aminoácidos
8.
J Sci Food Agric ; 102(14): 6707-6717, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35620809

RESUMO

BACKGROUND: The interactions between various food colloids in different systems (e.g., dispersions, emulsions, creams) have a bearing on the processing and characteristics of food systems. Hydrophilic polysaccharides have been proven to have the potential to fabricate the above systems. In the present work, hydroxypropyl methylcellulose (HPMC) was partially replaced by the insoluble soybean fiber (ISF) extracted from defatted okara to prepare mixing dispersions, oil-in-water emulsions and whipped creams. RESULTS: The presented work showed that as the proportion of ISF increased, the foaming properties of ISF/HPMC dispersions were enhanced, the absolute value of the ζ-potential and the particle size of the emulsions increased, while the heat stability and centrifugal stability first increased and then decreased. Upon whipping, the loss angle (tan δ) decreased first and then increased, while the overrun, foam stability and cream stability, as well as the elastic modulus (G'), presented the opposite trend. CONCLUSION: These results indicated that an appropriate amount (40-60%) of ISF in the ISF/HPMC systems enhanced the foaming and emulsifying capacities of mixtures and the stability of the resultant emulsion; subsequently, the whipping performance and whipped cream network structure were strengthened, suggesting that ISF has great potential for application in whipped cream as a 'green' and safe food ingredient. © 2022 Society of Chemical Industry.


Assuntos
Ingredientes de Alimentos , Glycine max , Emulsificantes/química , Emulsões/química , Derivados da Hipromelose , Polissacarídeos , Água
9.
J Sci Food Agric ; 101(9): 3685-3692, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33301177

RESUMO

BACKGROUND: The role of protein-polysaccharide interactions and their mixtures has been a vital factor affecting the formation and stability of food emulsions. Okara protein (OP), which is extracted from the by-product of soybean processing, has received much attention because of its abundant sources and potential attributes with respect to food formulation. Carboxymethyl cellulose (CMC), a well-known food-grade polysaccharide additive, has been widely utilized in the protein-polysaccharide system, whereas, among the proteins, the role of OP has not yet been explored. RESULTS: The present study first assessed the ζ-potential and hydrodynamic diameter of aqueous mixtures containing OP (1.0 wt%) and CMC (0-0.5 wt%), followed by the investigation of OP-CMC mixtures stabilized O/W emulsions. As CMC increased, oil droplet size, surface protein adsorption, apparent viscosity and storage modulus increased, whereas the loss tangent decreased. CONCLUSION: CMC resulted in emulsion destabilization compared to emulsions without CMC, whereas a higher concentration of CMC promoted emulsion stability against creaming for emulsions in the presence of CMC. The results provide information with respect to OP and CMC being incorporated into food formulations and also strengthen our understanding of the related mechanism, in addition to facilitating the further utilization of OP. © 2020 Society of Chemical Industry.


Assuntos
Carboximetilcelulose Sódica/química , Emulsões/química , Proteínas de Plantas/química , Polissacarídeos/química , Óleos/química , Reologia , Alimentos de Soja , Viscosidade , Água/química
10.
Langmuir ; 35(32): 10572-10581, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31310554

RESUMO

This study provides fundamental information about the influence of salt on the physicochemical stability of oregano essential oil (EO) and its main components incorporated in a nanoemulsion delivery system containing Tween 80 (T80) emulsifier. The emulsion stability was found to be strongly correlated with the lipid phase composition and the type of salts. The oregano essential oil nanoemulsions remained stable for several weeks in the absence of salts. Moreover, they were insensitive to tetrabutylammonium bromide, whereas similar to carvacrol emulsions, they exhibited a rapid phase separation and oiling-off in the presence of sodium chloride. On the other hand, high oleic sunflower oil (HOSO) and p-cymene emulsions remained stable in the presence of NaCl. Addition of 70 and 80% HOSO to the lipid phase of oregano EO and carvacrol, respectively, was found to be sufficient for the formation of emulsions with a high stability to 1.7 M NaCl. Hereby, the morphology of the oregano EO emulsions after 30 days of storage in the presence of NaCl was visualized using a transmission electron microscope. The determination of the surface load and area per surfactant molecule by interfacial tension (IFT) measurements and quartz crystal microbalance with dissipation revealed the dehydration of the polyoxyethylene groups of T80 in the presence of salt. The thickness of the T80 adsorbed layer onto solid hydrophobic and hydrophilic surfaces was significantly lower (p < 0.05) in the presence of sodium chloride. It is hypothesized that a combination of Ostwald ripening and coalescence due to an IFT increase and dehydration was responsible for the instability of the emulsions containing the more polar oregano EO and carvacrol in the presence of salt. The results obtained in this study could be useful for the formulation of essential oil nanoemulsions in the presence of salts applicable in food, pharmaceutical, and personal care products.


Assuntos
Óleos Voláteis , Origanum/crescimento & desenvolvimento , Polissorbatos , Tolerância ao Sal/efeitos dos fármacos , Óleo de Girassol , Água , Emulsões , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Polissorbatos/química , Polissorbatos/farmacologia , Óleo de Girassol/química , Óleo de Girassol/farmacologia , Água/química , Água/farmacologia
11.
Magn Reson Chem ; 57(9): 674-685, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30680797

RESUMO

A time-domain 1 H nuclear magnetic resonance relaxometry method was elaborated for the rapid microstructural characterization of mozzarella cheese. For this purpose, there is a strong need to know how the experimentally determined T2 relaxation time distribution can be related to specific constituents in mozzarella. In this study, a detailed investigation is offered for fresh and aged low-moisture mozzarella cheese, often applied as a pizza cheese, by application of both a conventional Carr-Purcell-Meiboom-Gill (CPMG) sequence and a free-induction decay CPMG (FID-CPMG) sequence. The relaxation behavior was further elucidated by addition of deuterium oxide and by mild heat treatment of samples. The relaxation times of water protons in mozzarella were found to range from a few microseconds to some tens of milliseconds (in aged mozzarella) or to about hundred milliseconds (in fresh mozzarella). The upper limit of the T2 distribution can even be extended to the seconds range upon releasing water protons from the mozzarella matrix using a mild heat treatment or upon addition of deuterated water. Both stimuli also provided evidence for the absorption of water into the cheese matrix. The potential release and uptake of water demonstrated that mozzarella acts as a very dynamic system during production and storage. The detected differences in the behavior of the water fraction between fresh and aged low-moisture mozzarella might be utilized to study the influence of either production and/or storage conditions on the cheese ripening process.

12.
Magn Reson Chem ; 57(9): 707-718, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30671997

RESUMO

Water-in-oil-in-water (W/O/W) double emulsions are a promising technology for encapsulation applications of water soluble compounds with respect to functional food systems. Yet molecular transport through the oil phase is a well-known problem for liquid oil-based double emulsions. The influence of network crystallization in the oil phase of W/O/W globules was evaluated by NMR and laser light scattering experiments on both a liquid oil-based double emulsion and a solid fat-based double emulsion. Water transport was assessed by low-resolution NMR diffusometry and by an osmotically induced swelling or shrinking experiment, whereas manganese ion permeation was followed by means of T2 -relaxometry. The solid fat-based W/O/W globules contained a crystal network with about 80% solid fat. This W/O/W emulsion showed a reduced molecular water exchange and a slower manganese ion influx in the considered time frame, whereas its globule size remained stable under the applied osmotic gradients. The reduced permeability of the oil phase is assumed to be caused by the increased tortuosity of the diffusive path imposed by the crystal network. This solid network also provided mechanical strength to the W/O/W globules to counteract the applied osmotic forces.

13.
Compr Rev Food Sci Food Saf ; 18(1): 84-105, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33337021

RESUMO

To control and enhance protein functionality is a major challenge for food scientists. In this context, research on food protein fibril formation, especially amyloid fibril formation, holds much promise. We here first provide a concise overview of conditions, which affect amyloid formation in food proteins. Particular attention is directed towards amyloid core regions because these sequences promote ordered aggregation. Better understanding of this process will be key to tailor the fibril formation process. Especially seeding, that is, adding preformed protein fibrils to protein solutions to accelerate fibril formation holds promise to tailor aggregation and fibril techno-functionality. Some studies have already indicated that food protein fibrillation indeed improves their techno-functionality. However, much more research is necessary to establish whether protein fibrils are useful in complex food systems and whether and to what extent they resist food processing unit operations. In this review the effect of amyloid formation on gelation, interfacial properties, foaming, and emulsification is discussed. Despite their prevalent role as functional structures, amyloids also receive a lot of attention due to their association with protein deposition diseases, prompting us to thoroughly investigate the potential health impact of amyloid-like aggregates in food. A literature review on the effect of the different stages of the human digestive process on amyloid toxicity leads us to conclude that food-derived amyloid fibrils (even those with potential pathogenic properties) very likely have minimal impact on human health. Nevertheless, prior to wide-spread application of the technology, it is highly advisable to further verify the lack of toxicity of food-derived amyloid fibrils.

14.
Biotechnol Bioeng ; 113(3): 550-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26301720

RESUMO

Although sophorolipids (SLs) produced by S. bombicola are a real showcase for the industrialization of microbial biosurfactants, some important drawbacks are associated with this efficient biological process, e.g., the simultaneous production of acidic and lactonic SLs. Depending on the application, there is a requirement for the naturally produced mixture to be manipulated to give defined ratios of the components. Recently, the enzyme responsible for the lactonization of SLs was discovered. The discovery of the gene encoding this lactone esterase (sble) enabled the development of promising S. bombicola strains producing either solely lactonic (using a sble overexpression strain described in this paper: oe sble) or solely acidic SLs (using a sble deletion strain, which was recently described, but not characterized yet: Δsble). The new S. bombicola strains were used to investigate the production processes (fermentation and purification) of either lactonic or acidic SLs. The strains maintain the high inherent productivities of the wild-type or even perform slightly better and thus represent a realistic industrial opportunity. 100% acidic SLs with a mixed acetylation pattern were obtained for the Δsble strain, while the inherent capacity to selectively produce lactonic SLs was significantly increased (+42%) for the oe sble strain (99% lactonic SLs). Moreover, the regulatory effect of citrate on lactone SL formation for the wild-type was absent in this new strain, which indicates that it is more robust and better suited for the industrial production of lactonic SLs. Basic parameters were determined for the purified SLs, which confirm that the two new strains produce molecules with distinctive properties of which the application potential can now easily be investigated independently.


Assuntos
Produtos Biológicos/metabolismo , Esterases/metabolismo , Glicolipídeos/metabolismo , Lactonas/metabolismo , Saccharomycetales/enzimologia , Saccharomycetales/metabolismo , Tensoativos/metabolismo , Esterases/genética , Deleção de Genes , Expressão Gênica , Engenharia Metabólica , Saccharomycetales/genética
15.
Environ Res ; 142: 207-14, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26164115

RESUMO

The stability of engineered nanoparticles (ENPs) in complex aqueous matrices is a key determinant of their fate and potential toxicity towards the aquatic environment and human health. Metal oxide nanoparticles, such as CeO2 ENPs, are increasingly being incorporated into a wide range of industrial and commercial applications, which will undoubtedly result in their (unintentional) release into the environment. Hereby, the behaviour and fate of CeO2 ENPs could potentially serve as model for other nanoparticles that possess similar characteristics. The present study examined the stability and settling of CeO2 ENPs (7.3±1.4 nm) as well as Ce(3+) ions in 10 distinct natural surface waters during 7d, under stagnant and isothermal experimental conditions. Natural water samples were collected throughout Flanders (Belgium) and were thoroughly characterized. For the majority of the surface waters, a substantial depletion (>95%) of the initially added CeO2 ENPs was observed just below the liquid surface of the water samples after 7d. In all cases, the reduction was considerably higher for CeO2 ENPs than for Ce(3+) ions (<68%). A first-order kinetics model was able to describe the observed time-dependant removal of both CeO2 ENPs (R(2)≥0.998) and Ce(3+) ions (R(2)≥0.812) from the water column, at least in case notable sedimentation occurred over time. Solution-pH appeared to be a prime parameter governing nanoparticle colloidal stability. Moreover, the suspended solids (TSS) content also seemed to be an important factor affecting the settling rate and residual fraction of CeO2 ENPs as well as Ce(3+) ions in natural surface waters. Correlation results also suggest potential association and co-precipitation of CeO2 ENPs with aluminium- and iron-containing natural colloidal material. The CeO2 ENPs remained stable in dispersion in surface water characterized by a low pH, ionic strength (IS), and TSS content, indicating the eventual stability and settling behaviour of the nanoparticles was likely determined by a combination of physicochemical parameters. Finally, ionic release from the nanoparticle surface was also examined and appeared to be negligible in all of the tested natural waters.


Assuntos
Cério/análise , Nanopartículas Metálicas/análise , Poluentes Químicos da Água/análise , Bélgica , Monitoramento Ambiental , Água Doce/análise , Concentração de Íons de Hidrogênio
17.
Artigo em Inglês | MEDLINE | ID: mdl-38507391

RESUMO

PGPR is an emulsifier (E476) widely used in the food industry. In this study, a gas chromatography-flame ionisation detection (GC-FID) method was developed for the quantitative characterisation of the polyglycerol composition of PGPR. The method was validated to analyse quantitatively the polyglycerol species in neat PGPR products and in PGPR samples present in a lipid matrix. This method consists of saponification, acidification and petroleum ether extraction to remove interfering fatty acids, neutralisation, silylation and finally GC-FID analysis. Phenyl ß-D-glucopyranoside was used as internal standard as sorbitol proved unsuitable due to its susceptibility to interference from Na/K chloride during silylation. The response factors of glycerol and diglycerol towards phenyl ß-D-glucopyranoside were determined using pure standards, while response factors of polyglycerols with a degree of polymerisation of at least 3 could be reliably estimated according to an effective carbon number (ECN) approach. The validity of the method applied to PGPR samples was further supported on the basis of a mass balance considering the experimentally determined polyglycerol and fatty acid content. Moreover, recoveries of di-, tri-, tetra- and pentaglycerol were more than 95% for various PGPR samples added to two different lipid matrices at 2 wt% and 5 wt% concentrations. Furthermore, the method proved to be very repeatable (with relative standard deviation values below 2.2%). On the other hand, the inevitable presence of glycerol in the lipid samples caused fouling of the detector and column overloading, requiring frequent cleaning of the detector and trimming off part of the column.


Assuntos
Glicerol , Lipídeos , Polímeros , Glicerol/análise , Glicerol/análogos & derivados , Polímeros/química , Cromatografia Gasosa , Lipídeos/análise , Lipídeos/química , Ácidos Ricinoleicos/análise , Ácidos Ricinoleicos/química , Ionização de Chama
18.
Foods ; 13(14)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39063320

RESUMO

It is important to differentiate milk with different thermostabilities for diverse applications in food products and for the appropriate selection of processing and maintenance of manufacturing facilities. In this review, an overview of the chemical changes in milk subjected to high-temperature heating is given. An emphasis is given to the studies of traditional and state-of-the-art strategies for assessing the milk thermostability, as well as their influencing factors. Traditional subjective and objective techniques have been used extensively in many studies for evaluating thermostability, whereas recent research has been focused on novel approaches with greater objectivity and accuracy, including innovative physical, spectroscopic, and predictive tools.

19.
Food Res Int ; 188: 114485, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823871

RESUMO

Whey protein isolate (WPI) is mainly composed of ß-lactoglobulin (ß-LG), α-lactalbumin (α-LA) and bovine serum albumin (BSA). The aim of this study was to compare and analyze the influence of WPI and its three main constituent proteins, as well as proportionally reconstituted WPI (R-WPI) on resveratrol. It was found that the storage stability of resveratrol was protected by WPI, not affected by R-WPI, but reduced by individual whey proteins at 45°C for 30 days. The rank of accelerated degradation of resveratrol by individual whey proteins was BSA > α-LA > ß-LG. The antioxidant activity, localization of resveratrol and oxidation of carrier proteins were determined by ABTS, H2O2 assay, synchronous fluorescence, carbonyl and circular dichroism. The non-covalent interactions and disulfide bonds between constituent proteins improved the antioxidant activity of the R-WPI-resveratrol complex, the oxidation stability of the carrier and the solvent shielding effect on resveratrol, which synergistically inhibited the degradation of resveratrol in R-WPI system. The results gave insight into elucidating the interaction mechanism of resveratrol with protein carriers.


Assuntos
Antioxidantes , Lactalbumina , Lactoglobulinas , Oxirredução , Resveratrol , Soroalbumina Bovina , Proteínas do Soro do Leite , Resveratrol/química , Resveratrol/farmacologia , Proteínas do Soro do Leite/química , Lactalbumina/química , Antioxidantes/química , Antioxidantes/farmacologia , Lactoglobulinas/química , Soroalbumina Bovina/química , Dicroísmo Circular
20.
Food Chem ; 454: 139803, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810448

RESUMO

In this work, effects of cellulose nanofiber/dihydromyricetin (CNF/DMY) ratio on the structural, antioxidant and emulsifying properties of the CNF/DMY mixtures were investigated. CNF integrated with DMY via hydrogen bonding and the antioxidant capacity of mixtures increased with decreasing CNF/DMY ratio (k). The oxidative stability of emulsions enhanced as the DMY content increased. Emulsions formed at Φ = 0.5 displayed larger size (about 25 µm), better viscoelasticity and centrifugal stability than those at Φ = 0.3 (about 23 µm). The emulsions at k = 17:3 and Φ = 0.5 exhibited the most excellent viscoelasticity. In conclusion, the DMY content in mixtures and the oil phase fraction exhibited distinct synergistic effects on the formation and characteristics of emulsions, and the emulsions could demonstrate superior oxidative and storage stability. These findings could provide a novel strategy to extend the shelf life of cellulose-based emulsions and related products.


Assuntos
Antioxidantes , Celulose , Emulsões , Flavonóis , Nanofibras , Celulose/química , Antioxidantes/química , Flavonóis/química , Nanofibras/química , Emulsões/química , Tamanho da Partícula , Emulsificantes/química , Oxirredução , Viscosidade
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