Application of edible coatings to partially dehydrated pineapple for use in fruit cereal products

[EN] The present work analyzes the application method and the effectiveness of edible coatings based on caseinates or chitosan in partially dehydrated pineapple for its use in dry fruit-cereal products. Commercial breakfast cereals and partially dehydrated pineapples prepared by osmotic dehydration and vacuum impregnation were used for the experiments. Four coating application techniques, working at atmospheric pressure or applying vacuum impregnation, were used for coating the pineapple samples. Coated and uncoated samples were stored, at 20 degrees C with breakfast cereals and were subsequently analyzed weekly during 6 months. Critical water activity and critical water content for the glass transition of the cereals at 20 degrees C were estimated as 0.60 and 9.1 g water/100 g of product, respectively. Results show that the application of coatings by vacuum impregnation and sample air drying after coating, considerably extends the shelf-life of the pineapple-cereal system when caseinate based coatings are used. Chitosan based coatings are less effective to limit water vapor transfer and the critical moisture content of cereals are reached during the storage period. (c) 2012 Elsevier Ltd. All rights reserved.The authors acknowledge the financial support from the Conselleria de Educacion de la Comunidad Valenciana through Project GVPRE/2008/355 and Universitat Politecnica de Valencia through Project PAID-06-08-3242 M.J. Fabra thanks the support of Campus de Excelencia Internacional from Universitat Politecnica de Valencia.Talens Oliag, P.; Pérez-Masià, R.; Fabra Rovira, MJ.; Vargas, M.; Chiralt, A. (2012). Application of edible coatings to partially dehydrated pineapple for use in fruit cereal products. Journal of Food Engineering. 112:86-93. https://doi.org/10.1016/j.jfoodeng.2012.03.022S869311

Sustainable bioactive pectin-based films to improve fruit safety via a circular economy approach.

This work reports on the valorisation of persimmon (Diospyros kaki Thunb.) for the development of food-grade antiviral coatings against major viral foodborne pathogens, human noroviruses (NoVs) and hepatitis A virus (HAV). Initially, the antiviral activity of polyphenol-rich pectin extracts with abundant non-covalent interactions (PPN), pectin extracts enriched with intact pectin-polyphenol ester and O-glycosyl bonds (PPC) and hydro-ethanolic polyphenol-rich extracts (EPE) was compared. Higher viral reductions were found for the pectin extracts rich in polyphenols, mainly in those containing covalent pectin-polyphenol interactions. This specific extract was mixed with commercial citrus pectin (CP) to develop active edible films. Dry films were analysed in terms of their optical, morphological, mechanical and barrier properties. Addition of the bioactive pectin persimmon extract resulted in more coloured films with lower transparency. The presence of covalently-linked polyphenols gave rise to stiffer films, with lower sorption capacity and more hydrophobic nature. The infectivity of MNV and HAV on fresh blueberries after the coating treatments was reduced by approximately 4.28 and 2.38 log, respectively, after overnight incubation, as compared to the controls, when 10% PPC was incorporated into the film. Higher amounts of PPC did not significantly improve the antiviral activity and a complete inactivation for both viruses was observed after 4 days of storage at 25 °C. This paper highlights the potential of persimmon discards as a cheap source of food-grade antiviral coatings with improved physicochemical properties as compared to commercial citrus pectin

Bioactive extracts from persimmon waste: influence of extraction conditions and ripeness.

In this work, a bioactive persimmon extract was produced from discarded fruits. A central composite design was used to evaluate the effect of different extraction parameters and ripeness stages of persimmon fruits on the total phenolic content and antioxidant activity of the resulting extracts. Significantly greater phenolic contents were obtained from immature persimmon (IP) fruits. The optimum IP extract with the conditions set by the experimental design was industrially up-scaled and its composition and functional properties were evaluated and compared with those obtained under lab-scale conditions. Both extracts contained significant protein (>20%) and phenolic contents (∼11-27 mg GA/g dry extract) and displayed significant antiviral activity against murine norovirus and hepatitis A virus. Moreover, the extract showed no toxicity and significantly reduced the fat content and the cellular ageing of Caenorhabditis elegans (C. elegans) without affecting the worm development. These effects were mediated by down-regulation of fat-7, suggesting an anti-lipogenic activity of this extract

Bioactive extracts from persimmon waste: influence of extraction conditions and ripeness

In this work, a bioactive persimmon extract was produced from discarded fruits. A central composite design was used to evaluate the effect of different extraction parameters and ripeness stages of persimmon fruits on the total phenolic content and antioxidant activity of the resulting extracts. Significantly greater phenolic contents were obtained from immature persimmon (IP) fruits. The optimum IP extract with the conditions set by the experimental design was industrially up-scaled and its composition and functional properties were evaluated and compared with those obtained under lab-scale conditions. Both extracts contained significant protein (>20%) and phenolic contents (similar to 11-27 mg GA/g dry extract) and displayed significant antiviral activity against murine norovirus and hepatitis A virus. Moreover, the extract showed no toxicity and significantly reduced the fat content and the cellular ageing of Caenorhabditis elegans (C. elegans) without affecting the worm development. These effects were mediated by down-regulation of fat-7, suggesting an anti-lipogenic activity of this extract

Lysozyme release from isolate pea protein and starch based films and their antimicrobial properties

The objective of the current research was to analyze the effects of the pea protein and corn starch films as well as the temperature influence (10 and 25 C) on the release of lysozyme to a food simulant (agar gel). Lysozyme concentration at different depths of food simulant was measured, as a function of diffusion time, through its enzyme activity. In both polymer matrices, a loss of lysozyme activity was observed after film formation. Diffusion of lysozyme was enhanced when temperature increased, mainly when pea protein films were tested. A higher retention of lysozyme in the film starch matrix was significantly detected which could be attributed to the different hydration degree of the film in contact with the agar medium and the different interactions between the enzyme and the film polymer chains. The antimicrobial effectiveness of pea protein and starch films containing lysozyme (0, 50, 75 and 100 mg lysozyme/g hydrocolloid), against Listeria monocytogenes was proved. At 10 C, both matrices were effective against the pathogen. At 25 C, the effectiveness of films significantly decreased and pea protein films showed the best antimicrobial activity.The authors acknowledge the financial support from the Spanish Ministerio de Economia y Competitividad throughout the project AGL2010-20694, con-financed with FEDER founds. Author M.J. Fabra thanks the Campus de Excelencia Internacional VLC/CAMPUS for their support.Fabra Rovira, MJ.; Sánchez González, L.; Chiralt Boix, MA. (2014). Lysozyme release from isolate pea protein and starch based films and their antimicrobial properties. Food Science and Technology. 55(1):22-26. https://doi.org/10.1016/j.lwt.2013.08.001S222655

Influence of the homogenization conditions and lipid self-association on properties of sodium caseinate based films containing oleic and stearic acids

[EN] The effect of the homogenization conditions of the film-forming emulsions and lipid self-association on the physical properties of sodium caseinate films containing oleic and stearic acids was studied. For this purpose, different film-forming emulsions were prepared by using different homogenization methods and were characterized as to particle size distribution and rheological properties. Likewise, mechanical, structural and optical properties and water vapour permeability (WVP) of the obtained films were also determined. While films containing stearic acid showed a laminar-like structure, oleic acid was more homogeneously dispersed in the film matrix. These differences in structure make the stearic acid films less flexible, showing more surface roughness and less gloss and transparency than films containing oleic acid. The film microstructure also affects the WVP. In this sense, for oleic acid films, water barrier efficiency increased when homogenization conditions were more intense, whereas for films containing stearic acid, the opposite effect was observed. This different behavior was attributed to the different kind of lipid self-association in the aqueous media, protein interactions and their impact on the final film microstructure. © 2010 Elsevier Ltd.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 Vicerectorate 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.Fabra Rovira, MJ.; Pérez Masiá, R.; Talens Oliag, P.; Chiralt, A. (2011). Influence of the homogenization conditions and lipid self-association on properties of sodium caseinate based films containing oleic and stearic acids. Food Hydrocolloids. 25(5):1112-1121. doi:10.1016/j.foodhyd.2010.10.008S1112112125

Influence of hydroxypropylmethylcellulose addition and homogenization conditions on properties and ageing of corn starch based films

[EN] Edible films based on corn starch, hydroxypropyl methylcellulose (HPMC) and their mixtures were prepared by using two different procedures to homogenize the film forming dispersions (rotor-stator and rotor-stator plus microfluidizer). The influence of both HPMC-starch ratio and the homogenization method on the structural, optical, tensile and barrier properties of the films was analysed. The ageing of the films was also studied by characterizing them after 5 weeks' storage. Starch re-crystallization in newly prepared and stored films was analysed by means of X-ray diffraction. HPMC-corn starch films showed phase separation of polymers, which was enhanced when microfluidization was applied to the film forming dispersion. Nevertheless, HPMC addition inhibited starch re-crystallization during storage, giving rise to more flexible films at the end of the period. Water barrier properties of starch films were hardly affected by the addition of HPMC, although oxygen permeability increased due to its poorer oxygen barrier properties.The authors acknowledge the financial support from the Spanish Ministerio de Economia y Competitividad throughout the project AGL2010-20694, co-financed with FEDER funds. 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 Universitat Politecnica de Valencia.Jiménez Marco, A.; Fabra Rovira, MJ.; Talens Oliag, P.; Chiralt, A. (2012). Influence of hydroxypropylmethylcellulose addition and homogenization conditions on properties and ageing of corn starch based films. Carbohydrate Polymers. 89(2):676-686. doi:10.1016/j.carbpol.2012.03.075S67668689

Effect of re-crystallization on tensile, optical and water vapour barrier properties of corn starch films containing fatty acids

[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.Jiménez Marco, A.; Fabra Rovira, MJ.; Talens Oliag, P.; Chiralt, A. (2012). Effect of re-crystallization on tensile, optical and water vapour barrier properties of corn starch films containing fatty acids. Food Hydrocolloids. 26(1):302-310. doi:10.1016/j.foodhyd.2011.06.009S30231026

Physical properties and antioxidant capacity of starch-sodium caseinate films containing lipids

[EN] Biodegradable films based on starch, sodium caseinate, glycerol and lipids (oleic acid and/or a-tocopherol) were obtained and evaluated in terms of microstructure, mechanical behaviour, barrier and optical properties and antioxidant capacity. The effect of film storage time on these properties was also analysed. The lipid incorporation provoked phase separation due to the different interaction between each polymer and lipids, although structural rearrangement of components during storage could be deduced from the change in mechanical behaviour. After storage, all films showed similar mechanical properties, but lipid containing films were more stretchable. Lipid addition did not induce a notable decreased in water vapour permeability of the films, but oxygen permeability highly increased when they contained oleic acid. All films were highly transparent, with very small differences among formulations, although their gloss values increased when lipids were added. The incorporation of a-tocopherol greatly increased the antioxidant capacity of the films which affected oxygen permeability.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.Jiménez Marco, A.; Fabra Rovira, MJ.; Talens Oliag, P.; Chiralt, A. (2013). Physical properties and antioxidant capacity of starch-sodium caseinate films containing lipids. Journal of Food Engineering. 116(3):695-702. doi:10.1016/j.jfoodeng.2013.01.010S695702116

Influence of temperature and NaCl on the release in aqueous liquid media of aroma compounds encapsulated in edible films

This work analyses the release of n-hexanal and D-limonene from edible films, previously encapsulated in the iota-carrageenan matrix (with and without lipid). Both volatile compounds have different physicochemical properties. The effect of temperature (25 degrees C and 37 degrees C) and dissolution medium (water and 0.9% NaCl) on the release and retention of aroma compounds were studied. Hydrophobicity and wettability properties of active iota-carrageenan films were also studied and they were related with the internal and surface microstructure of films. Results highlight that D-limonene is encapsulated in the lipid phase of the films decreasing the release in the salt medium. D-limonene, the most hydrophobic, was more sensitive to the temperature changes than hexanal. Thus, this work gives an idea of the release of aroma compounds encapsulated in iota-carrageenan films in aqueous media. (C) 2011 Elsevier Ltd. All rights reserved.Author M.J. Fabra thanks the support of Campus de Excelencia Internacional from Universidad Politecnica de Valencia. Authors also thank Aline Bonnotte from Centre de Microscopie Appliquee a la Biologie de l'Universite de Bourgogne Dijon for their assistance in the use of the ESEM. The authors wish to thank Prof. JP Gay for the English improvement.Fabra Rovira, MJ.; Chambin, O.; Voilley, A.; Gay, J.; Frédéric Debeaufort (2012). Influence of temperature and NaCl on the release in aqueous liquid media of aroma compounds encapsulated in edible films. Journal of Food Engineering. 108(1):30-36. doi:10.1016/j.jfoodeng.2011.07.035S3036108