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Probiotics were enumerated in each step of the encapsulation process and the resistance of encapsulated microorganisms was verified under stress (temperature, pH, sodium chloride and sucrose) and simulated gastrointestinal conditions (SGC). Lipid particles were effective in protecting the probiotics subjected to environmental stress conditions (ESC) and SGC, when compared to free cells. After 30 days of storage at 25 °C, the viability of probiotics encapsulated by spray chilling was about 7.2 log cfu/g, while in the freeze-dried lipid particles covered by gelatin and gum Arabic the viability of probiotics was approximately 6.7 log cfu/g. Both encapsulation methods investigated were successful in protecting the probiotics in SGC and ESC, indicating their potential for application in food. However, the viability of encapsulated probiotics during storage must still be improved.

Bilayer films using polyester blends (P) and starch (S) were obtained and characterized, incorporating carvacrol as active compound. Carvacrol was incorporated by spraying it between melt blended and compression moulded sheets or through its incorporation into the chloroform P solution used to obtain P cast films. Different PLA-PHBV ratios (75:25 and 65:35) were tested, with and without 15 wt% of PEG1000, whereas the 75:25 ratio with PEG was only used for cast sheets, based on its better overall properties. Mono and bilayers were characterized as to their tensile and water vapour barrier properties and thermal behaviour. Release kinetics of carvacrol in different food simulants and in in vitro antibacterial activity against Listeria innocua and Escherichia coli were also analysed. Incorporating carvacrol by spraying it between the polyester and starch sheets was not effective at retaining the compound in the bilayers. However, the incorporation of carvacrol into cast P films, and the subsequent formation of bilayers with the S sheets, was highly effective at providing practically total carvacrol retention. These active bilayers exhibited highly improved tensile and water vapour barrier capacity with respect to the S monolayer (87% reduction in WVP, 840% increase in elastic modulus) and inhibited the growth of L. innocua and E. coli from both P or S contact sides of bilayers, depending on the internal diffusion of carvacrol through the bilayer and its adequate release of the compound into the culture medium.

[EN] Electrospun poly-(epsilon-caprolactone) (PCL) fibre mats encapsulating Carvacrol (CA) were obtained with good encapsulation efficiency (85%) and CA load (11% in the fibre). These mats were effective at controlling the growth of Escherichia coli, when the surface density of CA loaded fibres was 1.2 or 1.8 mg/cm2, in line with the CA released into the culture medium that exceeded the MIC of the bacteria. However, they were not effective at controlling the growth of Listeria innocua, since a greater release of CA was necessary to achieve the MIC of this bacterium. It was not only the CA load in the fibres, but also its release capacity in the media that determined the antimicrobial effect. The fibre showed higher release rate and ratio in less polar simulants, D1 (50% ethanol) and D2 (isooctane) (representing fatty foodstuff), where practically the total amount of CA was released; whereas in more polar systems (simulants A (10% ethanol) and B (3% acetic acid)) a more limited CA delivery (60-75%) occurred, at a slower rate. The antimicrobial action of the active PCL mats was reproduced in multilayer starch films containing the CA-loaded electrospun PCL fibres between two starch sheets, with a slightly delayed response. In the multilayer films, a great reduction in the water vapour permeability was also observed with respect to that of starch films, without relevant changes in other functional properties of the films for packaging purposes., The authors thank the Ministerio de Economia y Competitividad (MINECO) of Spain, for the financial support for this study as a part of projects AGL2013-42989-R and AGL2016-76699-R. The author A. Tampau thanks MINECO for the pre-doctoral research grant # BES-2014-068100.

[EN] Six non-conventional techniques (microwave-assisted extraction, ultrasound-assisted extraction, enzyme-assisted extraction - with cellulase and Celluclast 1.5L, ultrasound-assisted extraction - heating treatment, and enzyme-assisted extraction - ultrasound treatment) and conventional citric acid extraction were applied to extract pectin from Malus domestica 'Falticeni' apple pomace, and were compared in terms of extraction yields and physicochemical properties of the pectins. Microwave extraction led to the highest extraction yield and the lowest pectin recovery was found for the extraction with Celluclast 1.5L. Pectin samples obtained by microwave extraction showed color parameters comparable to commercial apple and citrus pectin, and had high galacturonic acid content, increased equivalent weight and high degree of esterification and molecular weight. High galacturonic acid content, molecular weight and degree of esterification were also found for pectin extracted by ultrasonication. On the opposite side, enzymatically extracted pectins had high equivalent weight, but lower degree of esterification that classified pectin extracted with cellulase as low-methoxylated pectin. Pectins obtained by ultrasound-assisted extraction - heating treatment and microwave extraction showed thermal properties that were similar to that of commercial pectins. The rheological characterization of pectin samples highlighted the high viscosities of solutions prepared with pectin from the ultrasound- and microwave-assisted extractions, which were correlated with their molecular weight and galacturonic acid content., This work was supported from contract no. 18PFE/16.10.2018 funded by Ministry of Research and Innovation of Romania within Program 1 - Development of national research and development system, Subprogram 1.2 - Institutional Performance -RDI excellence funding projects. The author Mircea Oroian also acknowledge for the financial support of the Romania National Council for Higher Education Funding, CNFIS, project number CNFIS-FDI-2019-0600.

Konjac glucomannan (KGM) is consistently associated to the creation of a sense of fullness while slowing down physiological processes associated with the digestion of foods and absorption of nutrients. To formulate food containing KGM is difficult because it develops very high viscosity in aqueous solution. In the present study cheese pies containing increasing amounts of KWM were prepared in such a way that the gum was not fully hydrated with the double propose of having high doses of KGM in the formulations and the gum to develop its rheological properties when it reaches the gastric tract. The pies were then submitted to oral plus gastric in vitro digestion and the rheological properties of the digested pies measured and compared with the performance of the KGM alone. The viscoelastic properties were higher as the KGM content in the pies rose. In addition, the digested pies were more effective in the onset of solid-like structures than the gum alone at the same concentration. The instrumental texture of the pies was also measured indicating that higher KGM levels produced harder and more cohesive pies; these texture features would potentially enhance their expected satiating capacity. Pies liking decreased with the increase of KGM level in the formulations when 118 consumers with no information about the pies composition or KGM health benefit performed a hedonic sensory test., The authors are grateful to the Spanish Ministry of Science and Innovation for financial support (AGL2012-36753-C02-01). They would also like to thank Mary Georgina Hardinge for assistance in correcting the English manuscript.

[EN] The aim of this work has been to study the effectiveness of gliadin films cross-linked with cinnamaldehyde as systems for the release of the natural antimicrobial compound lysozyme. Prior to the incorporation of lysozyme, the gliadin film-forming solution was treated with different percentages of cinnamaldehyde as cross-linker, and glycerol was added as plasticizer. The effect of the concentration of the cross-linker on the swelling capacity and kinetics of release of the antimicrobial agent from the protein matrix was evaluated at pH 6.2. The antimicrobial activity of the films was assayed against Listeria innocua. The gliadin films cross-linked with cinnamaldehyde incorporating lysozyme preserved their integrity in water. The release rate of the antimicrobial agent was controlled by the reticulation of the protein matrix, thus a greater degree of cross-linking led to slower release of the active agent. Films with a loosely cross-linked structure released a greater amount of lysozyme, exhibiting greater antimicrobial activity. (C) 2014 Elsevier Ltd. All rights reserved., The authors would like to thank the Spanish Ministry of Science and Innovation (Projects AGL2009-08776 and CONSOLIDER-INGENIO CSD2007-00063 and Mari Pau Balaguer pre-doctoral FPI fellowship) and Xunta de Galicia (Plan Galego de Investigacion, Desenvolvemento e Innovacion Tecnoloxica - INCITE 2006-2010 Paula Fajardo post-doctoral fellowship) for financial support.

The physical, antioxidant and antimicrobial properties of chitosan (CH)-cinnamon leaf essential oil (C) films, containing or not oleic acid (OA), were evaluated. The addition of OA led an increase in surface charge and particle size of the film-forming dispersions. This is in agreement with a greater CH adsorption on the droplets containing OA and the entrapment of C compounds in the non-polar core of the OA molecule associations. OA contributed to a better retention of C in the film during its drying, diminished the changes in colour parameters provoked by C addition and reduced the film transparency. Water vapour permeability of CH films was reduced by OA incorporation while it increased when they contained only C. Every film containing C showed antioxidant and antifungal properties, depending on the C content (the higher the C content, the greater the effect). OA reduced the antifungal effectiveness of C containing films in line with its encapsulating effect on C compounds. All the coatings were effective in extending the shelf-life of cold-stored strawberries, mainly when CH was combined with C at the ratio 1: 0.5., The authors acknowledge the financial support provided by Universitat Politecnica de Valencia (UPPTE/2012/183) and Ministerio de Ciencia e Innovacion (AGL2010-20694). Author A. Perdones acknowledges Universitat Politecnica de Valencia for a doctoral grant.

Nanoparticles with a compact spherical structure and a narrow size distribution were prepared from a zein protein polymer by electrohydrodynamic atomization. The effects of key parameters of the process (polymer concentration, flow rate and applied voltage) on the size and morphology of the particles was studied. Zein nanoparticles could be obtained from zein concentrations ranging from 2.5% to 15% (w/w). The sizes of these particles, ranging from 175 to 900 nm, increased with increasing polymer concentration. Compact nanostructures were obtained for 2.5% and 5% zein solutions whereas 10% and 15% solutions yielded collapsed and shrunken particles. Flow rate also exerted an effect, the lower the flow rate the smaller the nanoparticles. The morphology of the nanoparticles did not change after incorporating curcumin in proportions ranging from 1: 500 to 1: 10 (curcumin: zein), and the encapsulation efficiency was around 85-90%. Fluorescence microscopy images showed that the nanostuctures obtained took the form of matrix systems with the curcumin homogeneously distributed in the zein matrix. The curcumin remained in the amorphous state in the nanoparticle, as revealed by X-Ray diffractometry, evidencing intimate contact with the polymer. After three months of storage at 23 degrees C and 43% relative humidity in the dark, neither the size or the morphology of the nanoparticles had undergone significant changes, nor had the curcumin content altered. Thanks to encapsulation, the curcumin presented good dispersion in an aqueous food matrix: semi-skimmed milk. (C) 2011 Elsevier Ltd. All rights reserved.

[EN] Starch films are very hygroscopic and undergo crystallization during processing and storage. In this work, fatty acids (SA, PA and OA) were incorporated into starch films containing glycerol as plasticizer, in order to reduce the hygroscopic character of the films and to improve water vapour permeability. Microstructural, mechanical, barrier and optical properties were studied in both non-stored films and those stored for 5 weeks. Fatty acid addition affected the main properties of films since mechanical resistance was decreased, water vapour permeability was reduced and gloss and transparency were reduced. The degree of starch and FA crystallinity increased with storage time and gave rise to changes in film properties: films became stiffer, less effective as water vapour barriers and less transparent and glossy. Saturated fatty acids were more efficient at reducing WVP as compared to oleic acid, but these differences decreased after storage due to the greater increase in crystallization of the former as it has been observed by X-ray diffraction. © 2011 Elsevier Ltd., The authors acknowledge the financial support from Spanish Ministerio de Educacion y Ciencia throughout the project AGL2010-20694. A. Jimenez also thanks Conselleria de Educacio de la Comunitat Valenciana for the FPI grant. Author M.J. Fabra thanks the support of Campus de Excelencia Internacional from Universidad Politecnica de Valencia. The authors also acknowledge the Electronic Microscopy Service of Universidad Politecnica de Valencia for their assistance in the use of SEM and B. Mari for his assistance in X-ray diffraction analysis.

Edible films, based on sodium caseinate containing three different concentrations of ferulic acid or alpha-tocopherol (20, 40 and 60 mg/g sodium caseinate), were obtained in order to evaluate the effect of these compounds on properties of the caseinate matrices. Special emphasis was placed on their effect on the films' oxygen barrier properties, which are decisive in the prevention of the oxidation of foods containing lipids. Films were characterized as to their tensile, optical and surface properties as well as their barrier properties to water vapor, oxygen and aroma compounds (n-hexanal and n-hexanol). Ferulic acid was more efficient at reducing oxygen and n-hexanal permeability than alpha-tocopherol. Although ferulic acid slightly increased the stiffness of films at low concentration, in general, both antioxidants slightly reduce mechanical resistance, water vapor permeability, gloss and transparency of the films., The authors acknowledge the financial support from the Spanish Ministerio de Educacion y Ciencia through the project AGL2007-65503/ALI, from the Conselleria de Educacion de la Comunidad Valenciana through the Project GVPRE/2008/355 and from Vice-rectorate for Research from UPV through the project PAID-06-08-3242. Author M.J. Fabra thanks the support of Campus de Excelencia Internacional from Universidad Politecnica de Valencia. Author A. Hambleton thanks CONACyT of Mexico for their support.

[EN] The water sorption behaviour and phase transitions of dairy proteins (ß-casein and ß-lactoglobulin), dextrans (dextran6 and dextran500) and their mixtures were studied at low water content. Freeze-dried polysaccharide samples containing between 20 and 80% dairy protein were equilibrated at different water activities (aw) between 0.11 and 0.75, at 25 °C. Water sorption isotherms of pure compounds and mixtures, as well as glass transition at different water activities were determined. Crystallization of polysaccharides was also investigated. BET and Gordon and Taylor equations were used to model water adsorption isotherms and glass transition temperature behaviour, respectively. Polysaccharides showed a higher water adsorption capacity than dairy proteins in the range of aw studied, which decreased with the addition of protein. The addition of ß-casein decreased the Tg values of dextran systems. This effect was attributed to water migration from ß-casein to the polysaccharide fraction following the formation of ß-casein hydrophobic interactions. Likewise, dairy proteins provoked an increase in the temperature of dextran crystallization and a decrease in the enthalpy. This effect did not reflect the increase of dextran molecular mobility in the presence of ß-casein but could be masked by other factors, like steric hindrance. The effect of dairy proteins, especially ß-casein, on the phase transitions of polysaccharides should be considered for controlling the Maillard reaction, as well as physical and chemical changes that occur during processing and storage of food systems. © 2011 Elsevier Ltd.