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Interactions between water and EVOH food packaging films / Interacciones entre el agua y películas de EVOH para el envasado de alimentos Full text
2000
Aucejo, S. | Catalá, R. | Gavara, R.
The transport of water in four EVOH copolymers commonly used in high barrier food packages was characterized through permeation (continuous flow) and gravimetric experiments at different rela tive humidities and 23 ± 2°C. Water sorption isotherms were fitted with the D'Arcy and Watts' equa tion. From these data, the value of the solubility coefficient (S, as defined by Henry's law) was deter mined and was found constant within a 0.2-0.75 water activity (a w) range. Water uptake at the same a w increased as the EVOH ethylene content decreased. The permeability coefficient (P) for water through EVOH was determined as a function of water activity. The permeability was constant within the range of 0.3-0.75 a w and decreased with EVOH ethylene content. At high relative humidities (a w > 0.75) the value of permeability increased by up to two orders of magnitude. In this range, the higher the ethylene content the lesser the value of P.
Show more [+] Less [-]Enhancing water solubility of phytosterols through Co-amorphization with food-grade coformers Full text
2025
Yuxin Li | Yingting Luo | Xuening Song | Yuzhuo Wang | Simiao Liu | Fazheng Ren | Lingyan Kong | Hao Zhang
Phytosterols (PS) offer significant health benefits in human diet, but its poor solubility limits its effectiveness and application. This study explored enhancing PS solubility by testing thirteen food-grade coformers, three preparation methods and proportions screening to obtain the optimal formulation. Nicotinamide (Nic) was identified as the most effective coformer. A 20:1 (w/w) PS-Nic co-amorphous (CM) mixture, prepared via freeze-drying, achieved a solubility of 1536.4 μg/mL, significantly higher than pure PS. X-ray diffraction and differential scanning calorimetry confirmed the amorphous state of the mixture. Fourier-transform infrared, Raman, and 1H NMR spectroscopies, along with molecular dynamics simulations, revealed strong intermolecular interactions between PS and Nic. The PS-Nic CM demonstrated up to 60% in vitro dissolution and release within 2 h and maintained stable after storage at 4 °C for 6 months and under accelerated conditions equivalent to 10 months at room temperature. In sum, the crystal structure of PS was altered, and formed a co-amorphous system by using Nic as the optimal ligand via lyophilization to increase solubility. These findings suggest that the PS-Nic CM system has potential applications in functional foods, offering a feasible strategy to enhance the bioavailability of PS.
Show more [+] Less [-]Analysis of the glyphosate herbicide in water, soil and food using derivatising agents Full text
2017
Gill, Jatinder Pal Kaur | Sethi, Nidhi | Mohan, Anand
Glyphosate is used widely to control weeds. Glyphosate is a broad spectrum, non-selective, systemic and post-emergent herbicide. Glyphosate excessive use and impact on the environment is promoting the analysis of glyphosate in water, soil and food materials. Methods to analyse glyphosate at low levels are needed because glyphosate has a short half-life due to easy microbial degradation. Glyphosate has a high polarity and solubility in water, has high binding affinity with soil and is non-volatile. The absence of chromophoric groups in the molecular structure makes the detection difficult. Therefore, detection can be achieved by derivatisation, which makes glyphosate more volatile and stable for spectroscopic analysis. Derivatisation is commonly done by alkyl chloroformates, acylating agents, 9-fluoroenylmethylchloroformate, 4-methoxybenzenesulfonylfluoride and o-phthalaldehyde. Immunosensors allow detection at microlevels. Nanocrystals and nanotechnology allow detection at nanolevels. Here, we review methods to derivatise and analyse glyphosate.
Show more [+] Less [-]Biosynthesis of food constituents: Vitamins. 2. Water-soluble vitamins: Part 2 - a review Full text
2007
Velisek, J.,Vysoka Skola Chemicko-technologicka, Prague (Czech Republic). Ustav Chemie a Analyzy Potravin | Cejpek, K.,Vysoka Skola Chemicko-technologicka, Prague (Czech Republic). Ustav Chemie a Analyzy Potravin
This review article gives a survey of the biosynthetic pathways that lead to water-soluble vitamins in microorganisms, plants and some animals. The biosynthetic pathways leading to some of the B-group vitamins (biotin, folacin, cobalamins) and to vitamin C are described in detail using reaction schemes and mechanisms with enzymes involved and detailed explanations based on chemical principles and mechanisms.
Show more [+] Less [-]β-lactoglobulin as food grade surfactant for clove oil-in-water and limonene-in-water emulsion droplets produced by microchannel emulsification Full text
2016
Purwanti, Nanik | Ichikawa, Sosaku | Neves, Marcos A. | Uemura, Kunihiko | Nakajima, Mitsutoshi | Kobayashi, Isao
Unheated and heat-aggregated β-lactoglobulin (β-lg) solutions were used to stabilize clove oil-in-water emulsion and limonene-in-water emulsion prepared by microchannel (MC) emulsification. The size of the MC array plate was 15 × 15 mm2 consisting of 100 parallel MCs fabricated on each side of the plate. The channels were 4 μm depth, 71 μm length, and 8.2 μm width, with the terrace length of 29.1 μm. Unheated and heat-aggregated β-lg effectively stabilized clove oil-in-water and limonene-in-water emulsions during production using MC emulsification. The emulsion droplets were steadily produced by the channels. The average diameter of clove oil droplets was around 17 μm, with both unheated and heat-aggregated β-lg, regardless of the concentration of β-lg. The average diameter of the limonene droplets was 18–26 μm depending on the conditions (unheated or heat-aggregated) and the concentration of β-lg. The coefficient of variation for all average droplet diameters was ≤8%, which was an indication of monodisperse droplets. Clove oil-in-water emulsion droplets became polydisperse within 2 h observation, whilst limonene-in-water emulsion droplets remained monodisperse over time. The stability of the oil droplets over time related to the solubility of the oil phases rather than the effects of β-lg as the surfactant. In addition, the droplet sizes at different surfactant concentrations seemed to relate to the viscosity ratio between the dispersed phase and the continuous phase rather than the effects of the surfactant.
Show more [+] Less [-]Water sorption thermodynamic behavior of whey protein isolate/ polyvinyl alcohol blends for food packaging Full text
2020
Lara, Bruna Rage Baldone | Dias, Marali Vilela | Guimarães Junior, Mario | de Andrade, Paulo Sérgio | de Souza Nascimento, Bruna | Ferreira, Laura Fonseca | Yoshida, Maria Irene
In food packaging systems, moisture content influences chemical and physical film properties, also determining processes such as food spoilage, and properties of food texture and crispiness level. The study of water permeation and sorption processes of new materials intended to be used as packaging is very important to determine the best application conditions and to predict the film behavior under different moisture conditions inside and/or outside the packaging. In order to determine the suitable temperature and water activity (aw) application conditions for whey protein isolate (WPI)/polyvinyl alcohol (PVOH) blends as food flexible packaging, water permeation and water sorption thermodynamic behavior of these materials were evaluated. WPI/PVOH films and blends had solubility preponderant over the diffusion on the water permeation process. Water sorption experimental data were well described by the GAB model, and curves showed a more expressive increase of water sorption at aw > 0.75, with lower equilibrium moistures (Ye) at room than at chilled temperatures. Differential enthalpy decreased and differential entropy increased by the Ye gain, and the occurrence of enthalpy-entropy compensation was confirmed with enthalpy driving the sorption process. The addition of PVOH to the WPI matrix made the water sorption process more spontaneous. Water sorption thermodynamic analysis indicates that the application of WPI/PVOH blends as packaging is best suitable for foods and external environments with aw below 0.75 and at room temperature.
Show more [+] Less [-]Recovery of fish [Mackerel] water-solublue protein as food material by addition of polymer coagulants.
1992
Ookawa T. | Ninomiya K. | Takahashi K. | Tsuchiya T. | Matsumoto J.J.
Improved oil solubilization in oil/water food grade microemulsions in the presence of polyols and ethanol Full text
2001
Garti, N. | Yaghmur, A. | Leser, M.E. | Clement, V. | Watzke, H.J.
Microemulsions based on five-component mixtures for food applications and improved oil solubilization have been studied. The compositions included water, oil phase [such as R(+)-limonene and medium-chain triglycerides (MCT)], short-chain alcohols (such as ethanol), polyols (propylene glycol and glycerol), and several surfactants and their corresponding mixtures (nonionic, such as ethoxylated sorbitan esters, polyglycerol esters, sugar ester, and anionic, such as phosphatidylcholine). The phase behavior of these systems is discussed with respect to the influence of polyols and short-chain alcohols on the degree of solubilization of oils in the aqueous phase. The alcohol and polyols modify the interfacial spontaneous curvature and the flexibility of the surfactant film, enhancing the oil solubilization capacity of the microemulsions. The solubilization of R(+)-limonene was dramatically improved in the presence of the alcohol and polyols, whereas the improvement of solubilization for triglycerides containing MCT was less pronounced. In some systems high oil solubilization was achieved, and some of them can be easily diluted to infinity both with the aqueous phase and with the oil phase. Viscosity measurements along selected dilution lines [characterized by a single continuous microemulsion region starting from a pseudo binary solution (surfactant/oil phase) to the microemulsion (water/polyol corner)] indicate that at a certain composition the system inverts from a W/O to an O/W microemulsion.
Show more [+] Less [-]Correlation of foodstuffs with ethanol–water mixtures with regard to the solubility of migrants from food contact materials Full text
2014
Seiler, Annika | Bach, Aurélie | Driffield, M. (Malcolm) | Paseiro Losada, Perfecto | Mercea, Peter | Tosa, Valer | Franz, Roland
Today most foods are available in a packed form. During storage, the migration of chemical substances from food packaging materials into food may occur and may therefore be a potential source of consumer exposure. To protect the consumer, standard migration tests are laid down in Regulation (EU) No. 10/2011. When using those migration tests and applying additional conservative conventions, estimated exposure is linked with large uncertainties including a certain margin of safety. Thus the research project FACET was initiated within the 7th Framework Programme of the European Commission with the aim of developing a probabilistic migration modelling framework which allows one (1) to calculate migration into foods under real conditions of use; and (2) to deliver realistic concentration estimates for consumer exposure modelling for complex packaging materials (including multi-material multilayer structures). The aim was to carry out within the framework of the FACET project a comprehensive systematic study on the solubility behaviour of foodstuffs for potentially migrating organic chemicals. Therefore a rapid and convenient method was established to obtain partition coefficients between polymer and food, K P/F. With this method approximately 700 time-dependent kinetic experiments from spiked polyethylene films were performed using model migrants, foods and ethanol–water mixtures. The partition coefficients of migrants between polymer and food (K P/F) were compared with those obtained using ethanol–water mixtures (K P/F’s) to investigate whether an allocation of food groups with common migration behaviour to certain ethanol–water mixtures could be made. These studies have confirmed that the solubility of a migrant is mainly dependent on the fat content in the food and on the ethanol concentration of ethanol–water mixtures. Therefore dissolution properties of generic food groups for migrants can be assigned to those of ethanol–water mixtures. All foodstuffs (including dry foods) when allocated to FACET model food group codes can be classified into a reduced number of food categories each represented by a corresponding ethanol–water equivalency.
Show more [+] Less [-]Solubility of lipophilic food emulsifiers in aqueous media, 1: Systems formed by water, ethanol and surfactants derived from sorbitan
1987
Riego Martin, M.B. | Gomez Herrera, C. (Consejo Superior de Investigaciones Cientificas, Sevilla (Spain). Instituto de la Grasa y sus Derivados)
Se determina el efecto de la presencia de etanol sobre la tension superficial de las disoluciones acuosas de monolaurato de sorbitano etoxilado con una media de 20 moles de oxido de etileno. La incorporacion del etanol reduce significativamente la tension superficial correspondiente a la concentracion micelar critica del tensioactivo disuelto en agua. Se establecen los diagramas de fases ternarios de los sistemas "agua/etanol/monooleato de sorbitano" y "agua/etanol/mezcla equimolecular de este tensioactivo y el producto resultante de la etoxilacion del mismo con una media de 20 moles de oxido de etileno". La solubilidad del agua en el monooleato de sorbitano viene incrementada por la presencia del etanol. Este incremento es mucho mayor en presencia del tensioactivo etoxilado. Se propone una in1547terpretacion de los resultados basada en los "parametros de solubili
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