Preparation and Properties of Glycerol Plasticized Starch/ Sepiolites Composites

2013 ◽  
Vol 634-638 ◽  
pp. 1955-1961
Author(s):  
Yuan Yuan Du ◽  
Peng Wu Zheng

Two sepiolites (SEPs) were respectively used as the fillers in glycerol plasticized-cassava starch (GPS) matrix by the casting process. Scanning electron microscopy proved that SEPs were dispersed well in the GPS matrix. Fourier transform infrared spectroscopy indicated that silanol groups at the external surface of SEPs could form the interaction with C-O-H and C-O-C groups in starch molecules. The introduction of SEPs improved the tensile strength, thermal stability, the pasting viscosity and restrained water vapor permeability, but reduced the elongation at break of the composites. SEP-fiber imparted the composites better properties than SEP-velvet, except for the resistance of moisture adsorption. SEP-velvet could decrease the water contents at the equilibrium of the composites.

Coatings ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 84
Author(s):  
Sijun Ma ◽  
Yuanrong Zheng ◽  
Ran Zhou ◽  
Ming Ma

Four kinds of edible composite films based on chitosan combined with additional substances (konjac glucomannan, cassava starch, maltodextrin and gelatin) and the addition of lysozyme were prepared and used as packaging materials for Mongolian cheese. The prepared composite films were evaluated using scanning electron microscopy and Fourier transform infrared spectroscopy. The physicochemical properties of all chitosan composite films, including thickness, viscosity, opacity, color, moisture content, water vapor permeability, tensile strength and elongation at break, were measured. The results show that Konjac glucomannan–chitosan composite film presented the strongest mechanical property and highest transparency. The cassava starch–chitosan composite film presented the highest water barrier property. The study on the storage characteristics of Mongolian cheese was evaluated at 4 °C. The results show that the cheese packaging by cassava starch–chitosan composite film presented better treatment performance in maintaining the quality, reducing weight loss and delayering microbial growth.


2018 ◽  
Vol 105 ◽  
pp. 637-644 ◽  
Author(s):  
M.K.S. Monteiro ◽  
V.R.L. Oliveira ◽  
F.K.G. Santos ◽  
E.L. Barros Neto ◽  
R.H.L. Leite ◽  
...  

2000 ◽  
Vol 9 (1) ◽  
pp. 23-35 ◽  
Author(s):  
P. TANADA-PALMU ◽  
H. HELÉN ◽  
L. HYVÖNEN

Edible films from wheat gluten were prepared with various amounts of glycerol as a plasticizer. Water vapor permeability, oxygen permeability, tensile strength and percentage elongation at break at different water activities ( aw ) were measured. Films with low amounts of glycerol had lower water vapor and oxygen permeabilities, higher tensile strength and lower elongation at break. Wheat gluten coatings reduced weight loss during two weeks of storage for cherry tomatoes and sharon fruits compared to uncoated controls. A bilayer film of wheat gluten and beeswax significantly lowered weight loss from coated cheese cubes compared to single layer coating of wheat gluten.;


Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1606
Author(s):  
Peng Yin ◽  
Jinglong Liu ◽  
Wen Zhou ◽  
Panxin Li

To improve the functional properties of starch-based films, chitin (CH) was prepared from shrimp shell powder and incorporated into corn starch (CS) matrix. Before blending, maleic anhydride (MA) was introduced as a cross-linker. Composite CS/MA-CH films were obtained by casting-evaporation approach. Mechanical property estimation showed that addition of 0–7 wt % MA-CH improved the tensile strength of starch films from 3.89 MPa to 9.32 MPa. Elongation at break of the films decreased with the addition of MA-CH, but the decrease was obviously reduced than previous studies. Morphology analysis revealed that MA-CH homogeneously dispersed in starch matrix and no cracks were found in the CS/MA-CH films. Incorporation of MA-CH decreased the water vapor permeability of starch films. The water uptake of the films was reduced when the dosage of MA-CH was below 5 wt %. Water contact angles of the starch films increased from 22° to 86° with 9 wt % MA-CH incorporation. Besides, the composite films showed better inhibition effect against Escherichia coli and Staphylococcus aureus than pure starch films.


2013 ◽  
Vol 750-752 ◽  
pp. 1582-1585
Author(s):  
Chun Hong Zhang ◽  
Nan Chang ◽  
Chen Li ◽  
Xin Hua Li

Zein was added into wheat gluten (WG) to prepare zein composite films (ZCF) in order to improve the properties of films. The film-forming ability, properties, surface microstructure and infrared spectrum of WG films and ZCF were investigated. The results show that the viscosity of film-forming solutions decrease, and uniformity become worse slightly, after zein added. ZCF are yellow, with metal luster, whose toughness and water retention increase. Compared to the control, the ZCF tensile strength (TS), elongation at break (EB) and resistance of oxygen are increased by 33.2%, 17.2% and 11.25%, and water vapor permeability (WVP) and transparency are decreased by 26.0% and 75.4% respectively. ZCF have better antibacterial properties than WG films. The inhibition effect on escherichia coli and staphylococcus aureus are increased by 36.36% and 32.89% respectively. Hydrogen bond interaction of ZCF become weak, and the surface of ZCF become smooth and evenly.


2012 ◽  
Vol 506 ◽  
pp. 311-314 ◽  
Author(s):  
W. Pimpa ◽  
C. Pimpa ◽  
P. Junsangsree

Fresh durian seed consists largely of starch and can be considered such a suitable raw material for producing biodegradable films. The aim of this work was to develop biodegradable films based on durian seed starch (DSS) and to characterize their water barrier, microscopic and mechanical properties. DSS films were prepared by casting with glycerol as plasticizer. Corn starch and cassava starch, commonly used in food processing, were chosen to prepare films and compare their properties to the DSS-based films. Using a second biopolymer, carboxymethyl cellulose (CMC), in the DSS based composite has been studied as a strategy to improve their important properties. Water vapor permeability and elongation values were improved significantly (p<0.05) when 5% (w/w DSS) CMC was incorporated. Therefore, preparing biodegradable films from DSS is a new alternative for using this raw material which is sometimes much cheaper than commercial starches


2010 ◽  
Vol 150-151 ◽  
pp. 1396-1399 ◽  
Author(s):  
Xi Hong Li ◽  
Kuan Guo ◽  
Xiao Yan Zhao

This paper explains and demonstrates the effects of beeswax on functional and structural properties of soy protein isolate films, containing different glycerol. The results showed that percentage elongation at break, water vapor permeability, and transparency of soy protein isolate films decreased when the beeswax content increased, but tensile strength and oxygen permeability increased. The higher the glycerol content, the higher the film water vapor permeability, oxygen permeability, and transparency. The results of differential scanning calorimetry and Fourier transform infrared spectroscopy suggested that beeswax cross-linked with soy protein isolate molecules via connecting with glycerol, composed the film matrix.


2013 ◽  
Vol 750-752 ◽  
pp. 1930-1933
Author(s):  
Jiang Ping Chang ◽  
Hong Li Li ◽  
Ying Jie Zhang ◽  
Guo Xian Zhou ◽  
Ming Long Yuan

The poly (lactide-co-trimethylene carbonate) copolymers are prepared by ring opening polymerization and catalyzed by SnOct and their films are prepared by blow molding. The 1HNMR study demonstrates that PLA-PTMC copolymers were successfully obtained and the graft way is A-B model. The water vapor permeability (WVP) of the films decreases with the increasing TMC content due to the formation of denser structure. The mechanical measurement reveals that the tensile strength of blown films has been declined with the increasing TMC content, but the elongation at break is improved and the tensile strength can be satisfied for the requirement of film product. Therefore, the copolymer film will be great prospect in the application of food and beverage packing.


Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4252
Author(s):  
Slađana Davidović ◽  
Miona Miljković ◽  
Milan Gordic ◽  
Gustavo Cabrera-Barjas ◽  
Aleksandra Nesic ◽  
...  

The development of edible films and coatings in the food packaging industry presents one of the modern strategies for protecting food products and ensuring their freshness and quality during their shelf lives. The application of microbial polysaccharides to the development of food package materials, as an alternative option to the commonly used plastic materials, is both economic and environmentally favorable. New edible films were developed using dextran from lactic acid bacterium Leuconostoc mesenteroides T3, and additionally plasticized by different concentrations of polyglycerol. The best tensile strength of the films was obtained using a formulation that contained 10 wt% of polyglycerol, which corresponded to a value of 4.6 MPa. The most flexible formulation, with elongation at break of 602%, was obtained with 30 wt% of polyglycerol. Water vapor permeability values of the films synthesized in this study were in the range of (3.45–8.81) ∗ 10−12 g/m s Pa. Such low values indicated that they could be efficient in preventing fruit from drying out during storage. Thus, the film formulations were used to coat blueberries in order to assess their quality during a storage time of 21 days at 8 °C. The results showed that dextran/polyglycerol films could be efficient in extending the shelf life of blueberries, which was evidenced by lower weight loss and total sugar solids values, as well as a delay in titratable acidity, in comparison to the uncoated blueberries.


2015 ◽  
Vol 4 (2) ◽  
pp. 103-14
Author(s):  
Gholamreza Kavoosi ◽  
Amin Shakiba ◽  
Mahmood Ghorbani ◽  
Seyed Mohammad Mahdi Dadfar ◽  
Amin Mohammadi Purfard

Background: Development of biodegradable and biocompatible films based on protein polymer with strong antioxidant and antibacterial activities has gradually obtained extensive concern in the world. In this study, the improvement of gelatin film properties incorporated with Ferula assa-foetida essential oil (FAO) as a potential antioxidant/antibacterial wound dressing film was investigated. Materials and Methods: Gelatin films were prepared from gelatin solutions (10% w/v) containing different concentration of FAO. The effect of FAO addition on water solubility, water swelling, water vapor permeability, mechanical behavior, light barrier properties as well as antioxidant and antibacterial activities of the films were examined. Results: Water solubility, water swelling and water vapor permeability for pure gelatin films were 29 ± 1.6%, 396 ± 8%, 0.23 ± 0.018 g.mm/m2.h, respectively. Incorporation of FAO into gelatin films caused a significant decrease in swelling and increase in solubility and water vapor permeability. Tensile strength, elastic modulus and elongation at break for pure gelatin films were 4.2 ± 0.4 MPa, 5.8 ± 4.2 MPa, 128 ± 8 %, respectively. Incorporation of FAO into gelatin films caused a significant decrease in tensile strength and elastic modulus and increase in elongation at break of the films. Gelatin film showed UV-visible light absorbance ranging from 280 to 480 nm with maximum absorbance at 420 nm. Gelatin/FAO films also exhibited excellent antioxidant ad antimicrobial activities. Conclusions: Our results suggested that gelatin/FAO films could be used as active films due to their excellent antioxidant and antimicrobial features for different biomedical applications including wound-dressing materials.[GMJ.2015;4(2):103-14]


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