Modification of Physico-Chemical Properties of Acryl-Coated Polypropylene Foils for Food Packaging by Reactive Particles from Oxygen Plasma

Gelatin is a proteinaceous substance composed of all the essential amino acids (except tryptophan) and derived from collagen using a hydrolysis technique. Hydrogels and modified composites based on gelatin are widely used in the food industry, biomedicine, pharmaceutical industry and food packaging materials due to their biocompatibility, biodegradability, nonimmunogenicity and ability to stimulate cell adhesion and proliferation. Gelatin can absorb 5-10 times its weight of water and is the main ingredient of hard and soft capsules in pharmaceutical industry. It melts above 30°C and easily releases biologically active compounds, nutrients and drugs in human gastrointestinal tract. In addition, gelatin contains arginine-glycine-asparagine RGD-sequences in the polymer structure and contributes to various functions such as antioxidant, anti-hypertensive, anti-microbial, tissue regeneration, wound healing, enhances bone formation and anti-cancer therapy. This article reports a brief overview of gelatin sources, gelatin preparation processes and its physico-chemical properties, as well as advances in the preparation of gelatin-based composite materials and hydrogels for tissue engineering, drug delivery, wound dressings, active packaging using various cross-linking techniques.

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Influence of Plasticizers Over Some Physico-chemical Properties of PLA

Materiale Plastice ◽

10.37358/mp.17.1.4789 ◽

2017 ◽

Vol 54 (1) ◽

pp. 73-78 ◽

Cited By ~ 9

Author(s):

Maria Rapa ◽

Raluca Nicoleta Darie Nita ◽

Cornelia Vasile

Keyword(s):

Thermal Properties ◽

Food Packaging ◽

Chemical Properties ◽

Melt Processing ◽

Main Task ◽

Mechanical And Thermal Properties ◽

Oxygen Barrier ◽

Physico Chemical ◽

Different Types ◽

Oxygen Barrier Property

The use of polylactic acid (PLA) for food packaging is limited because it has poor mechanical and thermal properties, low ductility, and its oxygen barrier property is quite poor compared with polymers obtained from petrochemical resources. One main task of processors is to modify these properties in such a way that PLA to be able to compete with conventional polymers such as polyethylene, polypropylene or poly(vinylchloride). Our studies were conducted to test the effect of different types of plasticizers on the PLA melt processing and also on its mechanical and thermal performance.

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Physico-Chemical and Antiadhesive Properties of Poly(Lactic Acid)/Grapevine Cane Extract Films against Food Pathogenic Microorganisms

Polymers ◽

10.3390/polym12122967 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2967

Author(s):

Edaena Pamela Díaz-Galindo ◽

Aleksandra Nesic ◽

Gustavo Cabrera-Barjas ◽

Octavio Dublan-García ◽

Rosa Isela Ventura-Aguilar ◽

...

Keyword(s):

Lactic Acid ◽

Water Vapor ◽

Food Packaging ◽

Chemical Properties ◽

Poly Lactic Acid ◽

Sustainable Food ◽

Water Vapor Barrier ◽

Physico Chemical ◽

Saccharomyces Pastorianus ◽

Film Formulation

The aim of this study was evaluation of the physico-chemical properties and adhesion of microorganisms on poly(lactic acid) (PLA)-based films loaded with grapevine cane extract (5–15 wt%). The films were processed in a compression molding machine and characterized by mechanical, thermal, water vapor barrier and microbiological tests. The best physical-chemical properties for PLA film containing 10 wt% of extract were obtained. The addition of 10 wt% of extract into PLA films led to decrease of tensile strength for 52% and increase in elongation at break for 30%. The water vapor barrier of this film formulation was enhanced for 55%. All films showed thermal stability up to 300 °C. The low release of the active compounds from films negatively influenced their antimicrobial and antifungal activity. Botrytis cinerea growth inhibition onto PLA containing extracts (PLA-E) films was in the range between 15 and 35%. On the other side, PLA/extract films exhibited the antiadhesive properties against Pseudomonas aeruginosa, Pectobacterium carotovorum, Saccharomyces pastorianus, and Listeria monocytogenes, which could imply their potential to be used as sustainable food packaging materials for preventing microbial contamination of food.

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Physico-chemical properties of biodegradable films of polyvinyl alcohol/sago starch for food packaging

Materials Today Proceedings ◽

10.1016/j.matpr.2019.06.056 ◽

2019 ◽

Vol 16 ◽

pp. 1819-1824 ◽

Cited By ~ 1

Author(s):

F.F. Hilmi ◽

M.U Wahit ◽

N.A Shukri ◽

Z. Ghazali ◽

A.Z. Zanuri

Keyword(s):

Polyvinyl Alcohol ◽

Food Packaging ◽

Chemical Properties ◽

Sago Starch ◽

Biodegradable Films ◽

Physico Chemical

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Approaches in Animal Proteins and Natural Polysaccharides Application for Food Packaging: Edible Film Production and Quality Estimation

Polymers ◽

10.3390/polym13101592 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1592

Author(s):

Andrey Lisitsyn ◽

Anastasia Semenova ◽

Viktoria Nasonova ◽

Ekaterina Polishchuk ◽

Natalia Revutskaya ◽

...

Keyword(s):

Food Packaging ◽

Chemical Properties ◽

Environmentally Friendly ◽

Edible Films ◽

Edible Film ◽

Packaging Materials ◽

Film Production ◽

Quality Estimation ◽

Physico Chemical ◽

Crosslinking Agents

Natural biopolymers are an interesting resource for edible films production, as they are environmentally friendly packaging materials. The possibilities of the application of main animal proteins and natural polysaccharides are considered in the review, including the sources, structure, and limitations of usage. The main ways for overcoming the limitations caused by the physico-chemical properties of biopolymers are also discussed, including composites approaches, plasticizers, and the addition of crosslinking agents. Approaches for the production of biopolymer-based films and coatings are classified according to wet and dried processes and considered depending on biopolymer types. The methods for mechanical, physico-chemical, hydration, and uniformity estimation of edible films are reviewed.

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Effects of Kappa-Carrageenan on the Physico-Chemical Properties of Thermoplastic Starch

KIMIKA ◽

10.26534/kimika.v26i1.10-16 ◽

2015 ◽

Vol 26 (1) ◽

pp. 10-16 ◽

Cited By ~ 2

Author(s):

Annabelle C. Flores ◽

Eric R. Punzalan ◽

Norberto G. Ambangan

Keyword(s):

Food Packaging ◽

Water Solubility ◽

Transmission Rate ◽

Low Cost ◽

Composite Films ◽

Chemical Properties ◽

Thermoplastic Starch ◽

Polymer Chains ◽

Physico Chemical ◽

Wide Range

Food packaging materials derived from renewable sources are highly sought due to their low cost and wide range of functional properties. This research reports on the fabrication and physico-chemical properties of composite films from cassava starch and κ-carrageenan.Characterization of the films by FTIR indicates physical entanglements between polymer chains. The water solubility of the films showed linear dependency on the κ-carrageenan content while the moisture content diminished with the addition of κ-carrageenan. . The mechanical property of the films showed that as the amount of κ-carrageenan increases, tensile strength exhibited improvement, the water activity (aw) increased, and pH became more basic, while % elongation weakened. Water vapour transmission rate (WVTR) improved significantly from 82.73 g/(m2.day) for pure thermoplastic starch to 11.31 g/(m2.day) for 90/10 % (w/w) starch/ κ-carrageenan ratio, which is comparable to WVTR of commercial polypropylene.

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Decoration of specific sites on freeze-fractured membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081565 ◽

1978 ◽

Vol 36 (2) ◽

pp. 140-141

Author(s):

H. Gross ◽

H. Moor

Keyword(s):

Pure Water ◽

Freeze Fracture ◽

Chemical Properties ◽

Surface Forces ◽

Sulfate Pentahydrate ◽

Copper Sulfate Pentahydrate ◽

Physico Chemical ◽

Water Of Hydration ◽

Small Container ◽

Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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PHYSICO CHEMICAL PROPERTIES OF NICKEL OXIDE AT HIGH TEMPERATURE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1976798 ◽

1976 ◽

Vol 37 (C7) ◽

pp. C7-438-C7-442 ◽

Cited By ~ 2

Author(s):

R. FARHI ◽

G. PETOT-ERVAS

Keyword(s):

High Temperature ◽

Nickel Oxide ◽

Chemical Properties ◽

Physico Chemical

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Physico-Chemical Properties of Recombinant Desulphatohirudin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645073 ◽

1990 ◽

Vol 63 (03) ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

A Electricwala ◽

L Irons ◽

R Wait ◽

R J G Carr ◽

R J Ling ◽

...

Keyword(s):

Molecular Weight ◽

Gel Filtration ◽

Chemical Properties ◽

Alpha Helix ◽

Apparent Molecular Weight ◽

Correlation Spectroscopy ◽

Nmr Studies ◽

Recombinant Hirudin ◽

Physico Chemical ◽

Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

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