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Brent S Murray - One of the best experts on this subject based on the ideXlab platform.
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interfacial rheology of Food Emulsifiers and proteins
Current Opinion in Colloid and Interface Science, 2002Co-Authors: Brent S MurrayAbstract:Abstract The scientific literature from 1997 (inclusive) to the present on the interfacial rheology of Emulsifiers and proteins of relevance to Food has been reviewed. Both shear and dilatational rheology of oil–water and air–water interfaces have been covered and the main factors affecting interfacial rheology have been tabulated. Special attention is paid to: the sensitivity of interfacial rheology to film composition and structure; the growing viewpoint of treating proteins films as a two-dimensional gel state; recent theoretical modelling of interfacial rheological effects; those few publications that attempt to relate interfacial rheology to bulk stability. It is concluded that there have been few major advances in the last 4 or 5 years, but the heterogeneity of such adsorbed films seems to be better recognised, both spatially and rheologically, with the challenge remaining to connect this picture to the stability of the corresponding bulk systems.
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Interfacial rheology of Food Emulsifiers and proteins
Current Opinion in Colloid and Interface Science, 2002Co-Authors: Brent S MurrayAbstract:The scientific literature from 1997 (inclusive) to the present on the interfacial rheology of Emulsifiers and proteins of relevance to Food has been reviewed. Both shear and dilatational rheology of oil-water interfaces have been covered and the main factors affecting interfacial rheology have been tabulated. Special attention is paid to: the sensitivity of interfacial rheology to film composition and structure; the growing viewpoint of treating proteins films as a two-dimensional gel state; recent theoretical modelling of interfacial rheological effects; those few publications that attempt to relate interfacial rheology to bulk stability. It is concluded that there have been few major advances in the last 4 or 5 years, but the heterogeneity of such adsorbed films seems to be better recognized, both spatially and rheologically, with the challenge remaining to connect this picture to the stability of the corresponding bulk sytems. © 2002 Elsevier Science Ltd. All rights reserved.
Wolfgang Schwack - One of the best experts on this subject based on the ideXlab platform.
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Determination of mono- and diacylglycerols from E 471 Food Emulsifiers in aerosol whipping cream by high-performance thin-layer chromatography–fluorescence detection
Analytical and Bioanalytical Chemistry, 2020Co-Authors: Claudia Oellig, Wolfgang Schwack, Max Blankart, Jörg Hinrichs, Michael GranvoglAbstract:Mono- and diacylglycerol (MAG and DAG) Emulsifiers (E 471) are widely applied to regulate techno-functional properties in different Food categories, for example, in dairy products. A method for the determination of MAG and DAG in aerosol whipping cream by high-performance thin-layer chromatography with fluorescence detection (HPTLC–FLD) after derivatization with primuline was developed. For sample preparation, aerosol whipping cream was mixed with ethanol, followed by the addition of water and liquid-liquid extraction with tert -butyl methyl ether. The sample extracts were analyzed by HPTLC–FLD on silica gel LiChrospher plates with n -pentane/ n -hexane/diethyl ether (22.5:22.5:55, v/v/v ) as mobile phase, when interfering matrix like cholesterol and triacylglycerols were successfully separated from the E 471 Food additives. For quantitation, an emulsifier with known composition was used as calibration standard and the fluorescent MAG and DAG were scanned at 366/> 400 nm. Limits of detection and quantitation of 4 and 11 mg/100 g aerosol whipping cream were obtained for both monostearin and 1,2-distearin, respectively, and allowed the reliable quantitation of MAG and DAG from E 471 far below commonly applied emulsifier amounts. Recoveries from model aerosol whipping cream with 400 mg E 471/100 g were determined in a calibration range of 200–600 mg E 471/100 g sample and ranged between 86 and 105% with relative standard deviations below 7%. In aerosol whipping creams from the German market, E 471 amounts ranged between 384 and 610 mg/100 g.
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effect of storage at high temperature on chemical composition and techno functional characteristics of e471 Food Emulsifiers applied to aerosol whipping cream
Journal of Food Engineering, 2020Co-Authors: Max Blankart, Wolfgang Schwack, Claudia Oellig, Sonja Averweg, Jörg HinrichsAbstract:Abstract Various Foods are processed with addition of mono- and diacylglycerol (MAG and DAG) Emulsifiers to adjust techno-functional properties. Exposure to and application of high temperatures during production, processing and transport of these Emulsifiers can induce compositional changes and thereby affect techno-functional properties. Emulsifiers were stored above their respective melting point and their chemical composition was determined by high-performance thin-layer chromatography–fluorescence detection. Storage for 8 weeks decreased the MAG content of a saturated MAG by about 36% by transesterification into 1,3-DAG, while a rearrangement of 1,2- into 1,3-DAG was observed for a saturated MAG/DAG emulsifier. Emulsifiers were applied to aerosol whipping cream, and viscosity, particle size, overrun, foam firmness and drainage were determined. The increasing 1,3-DAG content of the saturated MAG emulsifier was found to increase the drainage of aerosol whipping cream from 15% to 50%.
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characterization of e 472 Food Emulsifiers determination of bound and free fruit acids free glycerol and ash content
Journal of Chromatography A, 2020Co-Authors: Claudia Oellig, Katharina Link, Wolfgang SchwackAbstract:Abstract Emulsifiers of the type E 472 are esters of fruit acids and mono- and diacylglycerols (MAG and DAG), which are used to adjust techno-functional properties in various Food products. The most dominant representatives of E 472 Emulsifiers are acetic acid esters (E 472a), lactic acid esters (E 472b), citric acid esters (E 472c), and mono- and diacetyl tartaric acid esters (E 472e). For the determination of fruit acids, a high-performance liquid chromatography method with ultraviolet light (HPLC–UV) detection was developed. Free and total fruit acids were determined by reversed phase HPLC–UV analysis of untreated and saponified emulsifier extracts with 20 mM potassium hydrogen phosphate buffer (pH 2.6) as isocratic eluent. Limits of quantitation of 0.08–0.27 g free fruit acid/kg emulsifier and 4–14 g total fruit acid/kg granted a reliable method with recoveries for free and total fruit acids between 80 and 100% with relative standard deviations (%RSD) below 4%. For the quantitation of free glycerol by spectrophotometry, an enzymatic assay was optimized for the analysis of E 472 providing reliable results with %RSD values below 9%. In addition, the ash content of E 472 Emulsifiers was determined.
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characterization of e 472 Food Emulsifiers by high performance thin layer chromatography with fluorescence detection and mass spectrometry
Journal of Chromatography A, 2020Co-Authors: Claudia Oellig, Katharina Link, Wolfgang SchwackAbstract:Abstract Esters of fruit acids including acetic acid and mono- and diacylglycerols (MAG and DAG), also known as E 472 Emulsifiers, are used in the Food industry as Food additives to adjust techno-functional properties like viscosity, emulsion stability and foaming stability in various products, mainly dairy products. Based on the respective acids, E 472 Emulsifiers are classified in several categories with acetic acid esters (ACETEM, E 472a), lactic acid esters (LACTEM, E 472b), citric acid esters (CITREM, E 472c), and mono- and diacetyl tartaric acid esters (DATEM, E 472e) as the most prominent representatives. Besides fruit acid esters, E 472 Emulsifiers mainly comprise MAG, DAG, triacylglycerols, free fatty acids, free fruit acids and free glycerol in different amounts. Here we present an innovative and sensitive method for the characterization of the composition of E 472 Emulsifiers by high-performance thin-layer chromatography with fluorescence detection (HPTLC–FLD). For HPTLC–FLD, technical Emulsifiers were simply dissolved and analyzed on HPTLC silica gel plates after a two-fold development and derivatization with primuline, enabling the easy characterization and direct visual comparison of the emulsifier pattern (fingerprint) through the fluorescent lipid components under UV 366 nm. Thus, the HPTLC–FLD fingerprint approach represents a simple tool for the comparison of different samples, batches and categories of E 472. Coupling of HPTLC to mass spectrometry moreover enabled the identification of constituents of interest.
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characterization of e 471 Food Emulsifiers by high performance thin layer chromatography fluorescence detection
Journal of Chromatography A, 2018Co-Authors: Claudia Oellig, Klara Brändle, Wolfgang SchwackAbstract:Abstract Mono- and diacylglycerol (MAG and DAG) Emulsifiers, also known as Food additive E 471, are widely used to adjust techno-functional properties in various Foods. Besides MAGs and DAGs, E 471 Emulsifiers additionally comprise different amounts of triacylglycerols (TAGs) and free fatty acids (FFAs). MAGs, DAGs, TAGs and FFAs are generally determined by high-performance liquid chromatography (HPLC) or gas chromatography (GC) coupled to mass selective detection, analyzing the individual representatives of the lipid classes. In this work we present a rapid and sensitive method for the determination of MAGs, DAGs, TAGs and FFAs in E 471 Emulsifiers by high-performance thin-layer chromatography with fluorescence detection (HPTLC–FLD), including a response factor system for quantitation. Samples were simply dissolved and diluted with t-butyl methyl ether before a two-fold development was performed on primuline pre-impregnated LiChrospher silica gel plates with diethyl ether and n-pentane/n-hexane/diethyl ether (52:20:28, v/v/v) as the mobile phases to 18 and 75 mm, respectively. For quantitation, the plate was scanned in the fluorescence mode at UV 366/>400 nm, when the cumulative signal for each lipid class was used. Calibration was done with 1,2-distearin and amounts of lipid classes were calculated with response factors and expressed as monostearin, distearin, tristearin and stearic acid. Limits of detection and quantitation were 1 and 4 ng/zone, respectively, for 1,2-distearin. Thus, the HPTLC–FLD approach represents a simple, rapid and convenient screening alternative to HPLC and GC analysis of the individual compounds. Visual detection additionally enables an easy characterization and the direct comparison of Emulsifiers through the lipid class pattern, when utilized as a fingerprint.
Jeanne Andres - One of the best experts on this subject based on the ideXlab platform.
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retraction stable arrested non aqueous edible foams based on Food Emulsifiers
Food & Function, 2020Co-Authors: Jeanne AndresAbstract:Retraction of ‘Stable ‘arrested’ non-aqueous edible foams based on Food Emulsifiers’ by A. R. Patel, Food Funct., 2017, 8, 2115–2120.
Heizir F De Castro - One of the best experts on this subject based on the ideXlab platform.
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Enzymatic synthesis of monoglycerides by esterification reaction using Penicillium camembertii lipase immobilized on epoxy SiO2-PVA composite
Journal of Molecular Catalysis B: Enzymatic, 2020Co-Authors: Larissa Freitas, Ariela Veloso De Paula, Julio Cesar Dos Santos, Gisella Maria Zanin, Heizir F De CastroAbstract:Glycerol-fatty acid esterification has been conducted with lipase from Penicillium camembertii lipase immobilized on epoxy SiO(2)-PVA in solvent-free media, with the major product being 1-monoglyceride, a useful Food emulsifier. For a given set of initial conditions, the influence of reaction was measured in terms of product formation and selectivity using different fatty acids as acyl donors. Results were found to be relatively dependent of the chain length of the fatty acids, showing high specificity for both myristic and palmytic acids attaining final mixture that fulfills the requirements established by the World Health Organization to be used as Food Emulsifiers. (C) 2010 Elsevier B.V. All rights reserved
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enzymatic synthesis of monoglycerides by esterification reaction using penicillium camembertii lipase immobilized on epoxy sio2 pva composite
Journal of Molecular Catalysis B-enzymatic, 2010Co-Authors: Larissa Freitas, Ariela Veloso De Paula, Julio Cesar Dos Santos, Gisella Maria Zanin, Heizir F De CastroAbstract:Abstract Glycerol-fatty acid esterification has been conducted with lipase from Penicillium camembertii lipase immobilized on epoxy SiO 2 -PVA in solvent-free media, with the major product being 1-monoglyceride, a useful Food emulsifier. For a given set of initial conditions, the influence of reaction was measured in terms of product formation and selectivity using different fatty acids as acyl donors. Results were found to be relatively dependent of the chain length of the fatty acids, showing high specificity for both myristic and palmytic acids attaining final mixture that fulfills the requirements established by the World Health Organization to be used as Food Emulsifiers.
Rosario Rodriguez M Nino - One of the best experts on this subject based on the ideXlab platform.
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the effect of temperature on Food Emulsifiers at fluid fluid interfaces
Colloids and Surfaces B: Biointerfaces, 2001Co-Authors: Juan Rodriguez M Patino, Rosario Rodriguez M Nino, Cecilio Carrera Sanchez, J M Garcia, German Rodriguez Rodriguez Mateo, Marta Cejudo FernandezAbstract:Abstract Heat-induced interfacial aggregation of a whey protein isolate (WPI) with a high content of β-lactoglobulin (>92%), previously adsorbed at the oil–water interface, was studied by means of interfacial dynamic characteristics performed in an automatic drop tensiometer. Protein concentration in aqueous bulk phase ranging between 1×10−1 and 1×10−5 % wt/wt was studied as a variable. The experiments were carried out at temperatures ranging from 20–80°C with different thermal regimes. During the heating period, competition exists between the effect of temperature on the film fluidity and the increase in mechanical properties associated with the interfacial gelation process. Interfacial crystallisation of Food polar lipids (monopalmitin, monoolein, and monolaurin) previously adsorbed at the oil–water interface, was studied by interfacial dynamic characteristics (interfacial tension and surface dilational properties). The temperature, ranging between 40 and 2°C, and the lipid concentration in aqueous oil phase, ranging between 1×10−2 and 1×10−4 % wt/wt, were studied as variables. Significant changes in interfacial dynamic characteristics associated with interfacial lipid crystallisation were observed as a function of lipid concentration in the bulk phase. Interfacial crystallisation of Food polar lipids (monopalmitin, monoolein, and monolaurin) at the air–water interface, was studied by π-A isotherms performed in a Langmuir trough coupled with Brewster angle microscopy (BAM). A condensation in monoglyceride monolayers towards lower molecular area was observed as the temperature decreased. This effect was attributed to lipid crystallisation at lower temperatures. BAM images corroborated the effect of temperature on the monolayer structure, as a function of the monoglyceride type.
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interfacial characteristics of Food Emulsifiers proteins and lipids at the air water interface
Colloids and Surfaces B: Biointerfaces, 1999Co-Authors: Juan Rodriguez M Patino, Rosario Rodriguez M NinoAbstract:Abstract Factors affecting the interfacial characteristics (structure, stability, interfacial rheology, molecular diffusion, and rate of film formation) of Food Emulsifiers (polar lipids and proteins) at the air-aqueous phase interface are reviewed. The effect of interfacial and aqueous phase (water, and aqueous solutions of ethanol, glycerol, sugars, electrolytes, and pH) compositions have been analyzed as variables. Many measurement methods—such as tensiometry (Wilhelmy plate and pendant drop methods), and Langmuir- and Wilhelmy-type film balances—have been used in the experiments. The effect of the interfacial, aqueous phase composition, and operational conditions (surface density, surface pressure, and temperature) of Food Emulsifiers (lipids and proteins) at the air-aqueous phase interface are discussed.