278 research outputs found
Gelatin Manufacturing Process and Product
The present invention overcomes the deficiencies of the prior art by providing a process for manufacturing gelatin including cleaning a fowl-based source of collagen; subjecting the fowl-based source of collagen to at least one water extraction to extract gelatin from the collagen source; and separating the gelatin from any resulting by-products, wherein the process does not require an initial acid or lime pretreatment step. The present invention also includes a product made from this process
Property Modification of Edible Wheat, Gluten-Based Films
Procedures were developed to produce edible wheat, gluten-based films. A film was produced as a standard. Five additional films were then produced by modifying the initial film-forming solution. Modifications included changing the plasticizer, partially substituting wheat gluten with soy protein isolate and corn zein, and incorporating two acetylated monoglyceride products. All films were characterized by measuring selected mechanical properties, and permeabilities to water vapor and to oxygen. Comparison of the films, in terms of their measured properties, indicates ways to improve the overall performance of the standard film as a potential packaging material. A main limitation of all of the films was their poor water vapor barrier characteristics. On the other hand, they were very good oxygen barriers. All modified films were stronger than the standard in terms of tensile and bursting strength. The film containing soy protein was the strongest and the most uniform. Significant differences in measured properties were observed when the plasticizer was changed from glycerin to triethylene glycol
New Natural Injection-Moldable Composite Material from Sunflower Oil Cake
Through a twin-screw extrusion process the native structure of sunflower oil cake was completely
transformed (globular protein denaturation/texturization and husk fiber defibration) into a simpler
matrix-fiber structure, as could be seen on SEM micrographs. Further chemical reduction of
protein disulfide bridges greatly reduced the melt viscosity of the moistened composite that it
could be injection-molded. The molded specimens were tested and their tensile and flexural
properties and water absorption calculated. Their water resistance appeared to be particularly
high, and could be enhanced further after a thermal treatment (N2, 200°C). The proteic matrix
seemed to behave like a natural thermoset resin. Sunflower oil cake could be used without any
additives to make biodegradable, water resistant and exceptionally cheap material
Agro-materials : a bibliographic review
Facing the problems of plastic recycling and fossil resources exhaustion, the use of biomass to conceive new materials appears like a reasonable solution. Two axes of research are nowadays developed : on the one hand the synthesis of biodegradable plastics, whichever the methods may be, on the other hand the utilization of raw biopolymers, which is the object of this paper. From this perspective, the “plastic” properties of natural polymers, the caracteristics of the different classes of polymers, the use of charge in vegetable matrix and the possible means of improving the durability of these agro-materials are reviewed
The use of electric fields for edible coatings and films development and production: A review
Edible films and coatings can provide additional
protection for food, while being a fully biodegradable,
environmentally friendly packaging system. A diversity of
raw materials used to produce edible coatings and films are
extracted from marine and agricultural sources, including
animals and plants. Electric fields processing holds advantage
in producing safe, wholesome and nutritious food.
Recently, the presence of a moderate electric field during
the preparation of edible coatings and films was shown to
influence their main properties, demonstrating its usefulness
to tailor edible films and coatings for specific applications.
This manuscript reviews the main aspects of the use of
electric fields in the production of edible films and coatings,
including the effect in their transport and mechanical
properties, solubility and microstructure.Fundação para a Ciência e a Tecnologia (FCT), Portugal.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brasil
Enhancement of PLA-PVA surface adhesion in bilayer assemblies by PLA aminolisation
Data Availability: The raw/processed data required to reproduce these
findings cannot be shared at this time due to legal or ethical reasons.Poly(lactic acid) (PLA) and poly(vinyl alcohol) (PVA) present complementary barrier properties, and their combination in multilayer assemblies (laminates) could provide materials with more effective barrier capacity for food packaging purposes. However, their low chemical affinity compromises adequate polymer adhesion. Surface free energy modification of thermo-processed PLA films through treatment with 1,6-hexanediamine was used to enhance adhesion with polar PVA aqueous solutions. Treatments of 1 and 3 min increased the polar component of the solid surface tension, while treatments above 10 min provoked a corrosive effect in the films structure. Extensibility analyses of PVA solutions loaded with carvacrol (15 wt.%) and different Tween 85 ratios on PLA-activated surfaces allowed the selection of the 1-min aminolysed surface for obtaining PLA-PVA bilayers, by casting PVA solutions on the PLA films. This study revealed that despite aminolisation enhancing the PLA surface affinity for aqueous PVA solutions, casting-obtained bilayers presented limited oxygen barrier effectiveness due to heterogeneous thickness of PVA layer in the laminates.The authors acknowledge the financial support provided by the Ministerio de Economia y Competitividad (MINECO) of Spain (project AGL2016-76699-R). The author A. Tampau thanks MINECO for the pre-doctoral research grant #BES-2014-068100.info:eu-repo/semantics/publishedVersio
Bacterial cellulose-lactoferrin as an antimicrobial edible packaging
Bacterial cellulose (BC) films from two distinct sources (obtained by static culture with Gluconacetobacter xylinus ATCC 53582 (BC1) and from a commercial source (BC2)) were modified by bovine lactoferrin (bLF) adsorption. The functionalized films (BC+bLF) were assessed as edible antimicrobial packaging, for use in direct contact with highly perishable foods, specifically fresh sausage as a model of meat products. BC+bLF films and sausage casings were characterized regarding their water vapour permeability (WVP), mechanical properties, and bactericidal efficiency against two food pathogens, Escherichia coli and Staphylococcus aureus. Considering their edibility, an in vitro gastrointestinal tract model was used to study the changes occurring in the BC films during passage through the gastrointestinal tract. Moreover, the cytotoxicity of the BC films against 3T3 mouse embryo fibroblasts was evaluated.
BC1 and BC2 showed equivalent density, WVP and maximum tensile strength. The percentage of bactericidal efficiency of BC1 and BC2 with adsorbed bLF (BC1+bLF and BC2+bLF, respectively) in the standalone films and in inoculated fresh sausages, was similar against E. coli (mean reduction 69 % in the films per se versus 94 % in the sausages) and S. aureus (mean reduction 97 % in the films per se versus 36 % in the case sausages). Moreover, the BC1+bLF and BC2+bLF films significantly hindered the specific growth rate of both bacteria. Finally, no relevant cytotoxicity against 3T3 fibroblasts was found for the films before and after the simulated digestion. BC films with adsorbed bLF may constitute an approach in the development of bio-based edible antimicrobial packaging systems.The authors would like to acknowledge Portuguese Foundation
for Science and Technology (Fundação para a Ciência e Tecnologia)
for the research grants: Jorge Padrão SFRH/BD/64901/2009, Sara
Gonçalves SFRH/BD/63578/2009, João Pedro Silva SFRH/BPD/
64958/2009, Ana Cristina Pinheiro SFRH/BPD/101181/2014. V.
Sencadas thanks support from the COST Action MP1206: “Electrospun
nano-fibres for bio inspired composite materials and innovative
industrial applications” and MP1301: “New Generation
Biomimetic and Customized Implants for Bone Engineering”. The
authors would also like to thank the co-funded by the Programa
Operacional Regional do Norte (ON.2 e O Novo Norte), QREN,
FEDER Projects “BioHealth e Biotechnology and Bioengineering
approaches to improve health quality”, Ref. NORTE-07-0124-
FEDER-000027; “BioInd e Biotechnology and Bioengineering for
improved Industrial and Agro-Food processes”, REF. NORTE-07-
0124-FEDER-000028; Strategic Project PEST-C/FIS/UI607/2014;
Matepro eOptimizing Materials and Processes”, ref. NORTE-07-
0124-FEDER-000037; Strategic Project PEst-OE/EQB/LA0023/2013
and project ref. RECI/BBB-EBI/0179/2012 (project number FCOMP-
01-0124-FEDER-027462). Finally, the authors thank the Fundação
para a Ciência e Tecnologia for the strategic funding from the UID/
BIO/04469/2013 unit
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