The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Eric A Decker - One of the best experts on this subject based on the ideXlab platform.
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Inhibition of Citral degradation in model beverage emulsions using micelles and reverse micelles
Food Chemistry, 2010Co-Authors: Seung Jun Choi, Lulu Henson, Eric A Decker, L. Michael Popplewell, David Julian McclementsAbstract:Abstract Citral is a flavour component that is widely used in the beverage, food, and fragrance industries. Citral chemically degrades over time in aqueous solutions due to acid catalysed and oxidative reactions, leading to loss of desirable flavour and the formation of off-flavours. We examined the influence of surfactant micelles (Tween 80) in the aqueous phase and reverse micelles (polyglycerol polyricinoleate, PGPR) in the oil phase on the oil–water partitioning and chemical degradation of Citral in medium chain triglyceride oil-in-water emulsions. The percentage of Citral in the aqueous phase of the emulsions increased with increasing Tween 80 concentration, which was attributed to its incorporation within surfactant micelles. The rate of Citral degradation decreased as the Tween 80 concentration was increased from 1% to 5% w/w in both aqueous solutions and in emulsions, suggesting that Citral was protected from degradation once it was incorporated into micelles. The presence of reverse micelles (5% or 10% w/w PGPR) in the oil droplets decreased the percentage of Citral present within the aqueous phase of the emulsions, suggesting that Citral was preferentially incorporated into the reverse micelles. In addition, the presence of reverse micelles increased the chemical stability of Citral, possibly because a greater fraction remained within the oil droplets. These results show that micelle or reverse-micelle structures may be used to improve the chemical stability of Citral in beverage emulsions.
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influence of droplet charge on the chemical stability of Citral in oil in water emulsions
Journal of Food Science, 2010Co-Authors: Seung Jun Choi, Lulu Henson, Michael Popplewell, Eric A Decker, David Julian McclementsAbstract:: The chemical stability of Citral, a flavor component widely used in beverage, food, and fragrance products, in oil-in-water emulsions stabilized by surfactants with different charge characteristics was investigated. Emulsions were prepared using cationic (lauryl alginate, LAE), non-ionic (polyoxyethylene (23) lauryl ether, Brij 35), and anionic (sodium dodecyl sulfate, SDS) surfactants at pH 3.5. The Citral concentration decreased over time in all the emulsions, but the rate of decrease depended on surfactant type. After 7 d storage, the Citral concentrations remaining in the emulsions were around 60% for LAE- or Brij 35-stabilized emulsions and 10% for SDS-stabilized emulsions. An increase in the local proton (H(+)) concentration around negatively charged droplet surfaces may account for the more rapid Citral degradation observed in SDS-stabilized emulsions. A strong metal ion chelator (EDTA), which has previously been shown to be effective at increasing the oxidative stability of labile components, had no effect on Citral stability in LAE- or Brij 35-stabilized emulsions, but it slightly decreased the initial rate of Citral degradation in SDS-stabilized emulsions. These results suggest the surfactant type used to prepare emulsions should be controlled to improve the chemical stability of Citral in emulsion systems.
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Citral stability in oil in water emulsions with solid or liquid octadecane
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Seung Jun Choi, Jean Alamed, Lulu Henson, Michael Popplewell, Julian D Mcclements, Eric A DeckerAbstract:Citral stability in oil-in-water emulsions at pH 3.0 with solid or liquid octadecane was determined. Citral degradation was faster in anionic sodium dodecyl sulfate (SDS)-stabilized emulsions than non-ionic polyoxyethylene (23) lauryl ether (Brij)-stabilized emulsions. Crystallization of octadecane in both Brij- and SDS-stabilized emulsion droplets resulted in faster degradation of Citral. Crystallization of octadecane in emulsion droplets increased Citral partitioning into the aqueous phase, with 41−53% of the total Citral in the aqueous phase when octadecane was solid compared to 18−25% when octadecane was liquid. This research suggests that factors that increase partitioning of Citral out of the droplets of oil-in-water emulsions increase Citral degradation rates. These results suggest that the stability of Citral could be increased in oil-in-water emulsions by technologies that decrease its partitioning and exposure to acidic aqueous phases.
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chemical and physical stability of Citral and limonene in sodium dodecyl sulfate chitosan and gum arabic stabilized oil in water emulsions
Journal of Agricultural and Food Chemistry, 2007Co-Authors: D Djordjevic, Jean Alamed, Julian D Mcclements, Luisito Cercaci, Eric A DeckerAbstract:Citral and limonene are the major flavor components of citrus oils. Both of these compounds can undergo chemical degradation leading to loss of flavor and the formation of undesirable off-flavors. Engineering the interface of emulsion droplets with emulsifiers that inhibit chemical reactions could provide a novel technique to stabilize Citral and limonene. At present, emulsified flavor oils are usually stabilized by gum arabic (GA), which is a naturally occurring polysaccharide−protein complex. The objective of this study was to examine if Citral and limonene were more stable in emulsions stabilized with a sodium dodecyl sulfate (SDS)−chitosan complex than GA. Citral degraded less in GA-stabilized than in SDS−chitosan-stabilized emulsions at pH 3.0. However, SDS−chitosan-stabilized emulsions were more effective at retarding the formation of the Citral oxidation product, p-cymene, than GA-stabilized emulsions. Limonene degradation and the formation of limonene oxidation products, limonene oxide and carvone...
Zhongxiang Fang - One of the best experts on this subject based on the ideXlab platform.
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effect of kafirin based films incorporating Citral and quercetin on storage of fresh chicken fillets
Food Control, 2017Co-Authors: Stephen Gitonga Giteru, Stuart K Johnson, Zhongxiang FangAbstract:Abstract This study investigated mechanical and bioactive properties of kafirin films consisting of 2.5% Citral (CK), 2% quercetin (QK) or 1.25% Citral + 1% quercetin (CQK). Incorporation of Citral reduced the maximum stress (σmax) and stiffness, accompanied by an increase in the strain at break (eb), and yield stress (σy) of the films. Compared to the plain kafirin films (PK) and QK, Citral–containing films showed significant antimicrobial activity (p
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physicochemical and antimicrobial properties of Citral and quercetin incorporated kafirin based bioactive films
Food Chemistry, 2015Co-Authors: Stephen Gitonga Giteru, Ranil Coorey, Dean Bertolatti, Elizabeth Watkin, Stuart K Johnson, Zhongxiang FangAbstract:The aim of this study was to determine the physicochemical and antimicrobial properties of kafirin-based bioactive films incorporating the plant essential oil Citral and the polyphenol quercetin. The addition of quercetin and Citral both imparted a yellowish colour to the films. The tensile strength of films significantly decreased and elongation at break increased when Citral was incorporated, whereas addition of quercetin did not alter these two film parameters. The rate of water vapour transmission of the films decreased with Citral incorporation but the water vapour permeability was not affected by either Citral or quercetin incorporation. Furthermore, incorporation of Citral and quercetin significantly lowered the oxygen permeability of the films. Film made of kafirin alone had antimicrobial activity against Listeria monocytogenes, however, films incorporating Citral exhibited the highest antimicrobial activity against Campylobacter jejuni, L. monocytogenes, and Pseudomonas fluorescens. These results suggest that kafirin-based films incorporating Citral and quercetin have potential as bioactive packaging to improve food safety and quality.
Xiaoli Peng - One of the best experts on this subject based on the ideXlab platform.
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inhibition of cronobacter sakazakii virulence factors by Citral
Scientific Reports, 2017Co-Authors: Shan Chen, Wenting Zhang, Xiaoli PengAbstract:Cronobacter sakazakii is a foodborne pathogen associated with fatal forms of necrotizing enterocolitis, meningitis and sepsis in neonates and infants. The aim of this study was to determine whether Citral, a major component of lemongrass oil, could suppress putative virulence factors of C. sakazakii that contribute to infection. Sub-inhibitory concentrations of Citral significantly decreased motility, quorum sensing, biofilm formation and endotoxin production. Citral substantially reduced the adhesion and invasion of C. sakazakii to Caco-2 cells and decreased bacterial survival and replication within the RAW 264.7 macrophage cells. Citral also repressed the expression of eighteen genes involved in the virulence. These findings suggest that Citral has potential to be developed as an alternative or supplemental agent to mitigate the infections caused by C. sakazakii.
Seung Jun Choi - One of the best experts on this subject based on the ideXlab platform.
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Influence of structural properties of emulsifiers on Citral degradation in model emulsions
Food Science and Biotechnology, 2019Co-Authors: Ha Youn Song, Seung Jun ChoiAbstract:The storage stability of compounds encapsulated in emulsions is strongly influenced by the properties of the droplet interfacial membrane. To evaluate the effect of emulsion droplet interface thickness on the degradation of Citral, emulsions were prepared using polyoxyethylene alkyl ether-type emulsifiers with hydrophilic and hydrophobic groups of various sizes. Acid cyclization of Citral at pH 3 promoted faster degradation than that at pH 7. Ferrous irons accelerated Citral degradation in the emulsions at pH 3 but not at pH 7, because they decomposed the products of the acid-catalyzed cyclization of Citral through redox reactions rather than direct degradation. Water-soluble radicals dramatically increased the rate of Citral degradation, irrespective of pH. Notably, at low pH, the rate of Citral degradation by ferrous irons was higher than that by radicals. These findings suggest that the thickness and density of emulsion droplet surfaces are not important factors for inhibiting Citral degradation in emulsions.
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Effect of cosolvent and surfactant on the solubility and stability of Citral in a beverage model
Applied Biological Chemistry, 2016Co-Authors: Ju Won Park, Seung Jun ChoiAbstract:To evaluate how triacetin and surfactant affect the solubilization and stability of Citral, solutions containing Citral were prepared with polyoxyethylene stearyl ethers and triacetin. Triacetin had a significant impact on the increment of saturation concentration of Citral, and the Citral solubility increased as surfactants were added. However, an interaction effect between triacetin and surfactant on Citral solubility was not observed. At pH 3, the degradation rate constant of Citral gradually decreased with a proportion of the triacetin concentration. Additionally, the chemical degradation of Citral was considerably retarded in micelles built with surfactant. The surfactant with the smaller hydrophilic head exhibited higher Citral stabilization ability than the one with the larger hydrophilic head; however, a negative interaction effect between triacetin and surfactant on Citral stability in an acidic environment was observed.
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Inhibition of Citral degradation in model beverage emulsions using micelles and reverse micelles
Food Chemistry, 2010Co-Authors: Seung Jun Choi, Lulu Henson, Eric A Decker, L. Michael Popplewell, David Julian McclementsAbstract:Abstract Citral is a flavour component that is widely used in the beverage, food, and fragrance industries. Citral chemically degrades over time in aqueous solutions due to acid catalysed and oxidative reactions, leading to loss of desirable flavour and the formation of off-flavours. We examined the influence of surfactant micelles (Tween 80) in the aqueous phase and reverse micelles (polyglycerol polyricinoleate, PGPR) in the oil phase on the oil–water partitioning and chemical degradation of Citral in medium chain triglyceride oil-in-water emulsions. The percentage of Citral in the aqueous phase of the emulsions increased with increasing Tween 80 concentration, which was attributed to its incorporation within surfactant micelles. The rate of Citral degradation decreased as the Tween 80 concentration was increased from 1% to 5% w/w in both aqueous solutions and in emulsions, suggesting that Citral was protected from degradation once it was incorporated into micelles. The presence of reverse micelles (5% or 10% w/w PGPR) in the oil droplets decreased the percentage of Citral present within the aqueous phase of the emulsions, suggesting that Citral was preferentially incorporated into the reverse micelles. In addition, the presence of reverse micelles increased the chemical stability of Citral, possibly because a greater fraction remained within the oil droplets. These results show that micelle or reverse-micelle structures may be used to improve the chemical stability of Citral in beverage emulsions.
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influence of droplet charge on the chemical stability of Citral in oil in water emulsions
Journal of Food Science, 2010Co-Authors: Seung Jun Choi, Lulu Henson, Michael Popplewell, Eric A Decker, David Julian McclementsAbstract:: The chemical stability of Citral, a flavor component widely used in beverage, food, and fragrance products, in oil-in-water emulsions stabilized by surfactants with different charge characteristics was investigated. Emulsions were prepared using cationic (lauryl alginate, LAE), non-ionic (polyoxyethylene (23) lauryl ether, Brij 35), and anionic (sodium dodecyl sulfate, SDS) surfactants at pH 3.5. The Citral concentration decreased over time in all the emulsions, but the rate of decrease depended on surfactant type. After 7 d storage, the Citral concentrations remaining in the emulsions were around 60% for LAE- or Brij 35-stabilized emulsions and 10% for SDS-stabilized emulsions. An increase in the local proton (H(+)) concentration around negatively charged droplet surfaces may account for the more rapid Citral degradation observed in SDS-stabilized emulsions. A strong metal ion chelator (EDTA), which has previously been shown to be effective at increasing the oxidative stability of labile components, had no effect on Citral stability in LAE- or Brij 35-stabilized emulsions, but it slightly decreased the initial rate of Citral degradation in SDS-stabilized emulsions. These results suggest the surfactant type used to prepare emulsions should be controlled to improve the chemical stability of Citral in emulsion systems.
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Citral stability in oil in water emulsions with solid or liquid octadecane
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Seung Jun Choi, Jean Alamed, Lulu Henson, Michael Popplewell, Julian D Mcclements, Eric A DeckerAbstract:Citral stability in oil-in-water emulsions at pH 3.0 with solid or liquid octadecane was determined. Citral degradation was faster in anionic sodium dodecyl sulfate (SDS)-stabilized emulsions than non-ionic polyoxyethylene (23) lauryl ether (Brij)-stabilized emulsions. Crystallization of octadecane in both Brij- and SDS-stabilized emulsion droplets resulted in faster degradation of Citral. Crystallization of octadecane in emulsion droplets increased Citral partitioning into the aqueous phase, with 41−53% of the total Citral in the aqueous phase when octadecane was solid compared to 18−25% when octadecane was liquid. This research suggests that factors that increase partitioning of Citral out of the droplets of oil-in-water emulsions increase Citral degradation rates. These results suggest that the stability of Citral could be increased in oil-in-water emulsions by technologies that decrease its partitioning and exposure to acidic aqueous phases.
Stephen Gitonga Giteru - One of the best experts on this subject based on the ideXlab platform.
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effect of kafirin based films incorporating Citral and quercetin on storage of fresh chicken fillets
Food Control, 2017Co-Authors: Stephen Gitonga Giteru, Stuart K Johnson, Zhongxiang FangAbstract:Abstract This study investigated mechanical and bioactive properties of kafirin films consisting of 2.5% Citral (CK), 2% quercetin (QK) or 1.25% Citral + 1% quercetin (CQK). Incorporation of Citral reduced the maximum stress (σmax) and stiffness, accompanied by an increase in the strain at break (eb), and yield stress (σy) of the films. Compared to the plain kafirin films (PK) and QK, Citral–containing films showed significant antimicrobial activity (p
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physicochemical and antimicrobial properties of Citral and quercetin incorporated kafirin based bioactive films
Food Chemistry, 2015Co-Authors: Stephen Gitonga Giteru, Ranil Coorey, Dean Bertolatti, Elizabeth Watkin, Stuart K Johnson, Zhongxiang FangAbstract:The aim of this study was to determine the physicochemical and antimicrobial properties of kafirin-based bioactive films incorporating the plant essential oil Citral and the polyphenol quercetin. The addition of quercetin and Citral both imparted a yellowish colour to the films. The tensile strength of films significantly decreased and elongation at break increased when Citral was incorporated, whereas addition of quercetin did not alter these two film parameters. The rate of water vapour transmission of the films decreased with Citral incorporation but the water vapour permeability was not affected by either Citral or quercetin incorporation. Furthermore, incorporation of Citral and quercetin significantly lowered the oxygen permeability of the films. Film made of kafirin alone had antimicrobial activity against Listeria monocytogenes, however, films incorporating Citral exhibited the highest antimicrobial activity against Campylobacter jejuni, L. monocytogenes, and Pseudomonas fluorescens. These results suggest that kafirin-based films incorporating Citral and quercetin have potential as bioactive packaging to improve food safety and quality.