Optical and mechanical properties of thin films based on proteins

Guerrero, Pedro; Leceta, I.; Peñalba, M.; Caba, Koro de la

doi:10.1016/j.matlet.2014.03.116

Cited by 12 publications

(9 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…38 The TS and E of SPI lm decreased with the treatment of Zn NCs, indicating the lms were greatly soened, whereas the values of EB signicantly increased from 192.55% to 304.05%. The unfolded and loose structure of SPI modied by Cu NCs was also evidenced by the decrease of crystallinity in XRD results.…”

Section: Physical and Mechanical Propertiesmentioning

confidence: 94%

Endogenous Cu and Zn nanocluster-regulated soy protein isolate films: excellent hydrophobicity and flexibility

Kuang

Chen

et al. 2015

RSC Adv.

View full text Add to dashboard Cite

Water-soluble Cu nanoclusters (NCs) and Zn NCs capped with a vegetable protein, soy protein isolate (SPI), are designed and synthesized for regulation of the rigidity and flexibility of bio-films. The special bio-films from SPI modified by Cu NCs exhibit better mechanical property, and those modified with Zn NCs show better hydrophobic property. UV-vis absorption spectroscopy demonstrated that Cu NCs and Zn NCs have formed, and Fourier transform infrared spectroscopy revealed that there was no change in the basic structure of the protein, but the SPI molecule chains and functional groups might be influenced, which made the cross-linking density increase. X-ray photoelectron spectroscopy suggested Cu and Zn were in the zero-valent state. X-ray diffraction patterns of SPI films indicated that metal nanoclusters changed the conformation of SPI from compact to unfolded. Water vapor permeability, oxygen permeability and nitrogen permeability of these metal nanocluster-modified films have been improved, and these films are proven safe enough to be used in contact with food.

show abstract

Section: Physical and Mechanical Propertiesmentioning

confidence: 94%

Endogenous Cu and Zn nanocluster-regulated soy protein isolate films: excellent hydrophobicity and flexibility

Kuang

Chen

et al. 2015

RSC Adv.

View full text Add to dashboard Cite

show abstract

“…Routray et al [24] studied the effect of glycerol content on SPI plastic by analyzing tensile testing, Fourier transform infrared analysis (FTIR), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) and found that films obtained with 25% and 35% by weight of glycerol are flexible and have good mechanical properties. On further increasing the amount of glycerol causes a decrease in tensile strength and an increase in elongation at break due to the fact that glycerol reduces the interactions between protein chains, thereby increasing the chain mobility [25] . Kumar et al [26] examined the morphology, water resistance and biodegradation of banana fiber reinforced soy protein composites and concluded that the tensile strength and modulus was highest with SPI matrix having 25% (W/W) glycerol.…”

Section: Effect Of Plasticizers On Soy Protein Filmsmentioning

confidence: 99%

Soy Protein Based Green Composite: A Review

KM¹,

Singh²

2017

Res. Rev. J Mat. Sci

View full text Add to dashboard Cite

Today there are increasing demands for the use of environmental friendly materials that are biodegradable and can replace petroleum based synthetic polymers. Non degradability and environmentally hazardous nature of plastics and some composites are the main problems as plastic waste disposal management become a great challenge due to the unavailability of free land for solid waste disposal in regions of high population density [1]. Therefore scientists have focused their research on using materials from nature because of its biodegradability. Green composites are specific class of biocomposites, where a bio-based polymer matrix is reinforced by natural fibers. Synthetic plastics can be replaced by green composite products which make the environment free of plastic wastes. Soy protein has attracted great research interest for the development of environment friendly protein materials with potentially good properties, such as regeneration, biocompatibility, biodegradability, etc. [2-6]. In addition to its use as a food ingredient, nonfood applications of soy protein as polymeric materials have attracted increasing attention in recent years. Soy protein based composites show potential applications for housing, transportation and rigid packaging. Many researches on forming plastic and composites from soy protein resin were carried out [7-9]. Soy protein resins have been used to fabricate green composites for many applications such as hydrogels, adhesives, plastics, films, coatings and emulsifiers, and it has also been reported as a promising material for biotechnological and biomedical utilization. COMPOSITION OF SOY PROTEIN Soy protein is made from soybean that has been dehulled and deffated. Soybean contains roughly 18-20% oil, 40-45% protein, 25-30% carbohydrate, and 3% ash [10]. Soy proteins are complex macromolecules composed of amino acids such as cystine, arginine, lysine, hystidine, etc. which can be used for inter or intra molecular interaction as amino acids have many active sites available for molecular interaction [11]. Soy proteins are mostly globulin, with the 7S and 11S fractions representing 37% and 31% respectively, of the total extractable protein [12]. Soybean protein is commercially available in form of defatted soy flour (DSF), soy protein concentrate (SPC) and soy protein isolate (SPI). After soybeans are dehulled and the oil is extracted, the remaining protein and carbohydrate meal is ground into soy flour (SF) containing roughly 56% protein and 34% carbohydrate and is the least expensive of the three products. Soy protein concentrate (SPC) is produced by leaching out the water/alcohol-soluble carbohydrates from soy flour to obtain a product with 65-ABSTRACT Natural polymers can be obtained from natural resources such as plants, animals etc. Natural polymers are easily decomposable, ecofriendly, sustainable, low cost and help us to reduce the pollution. Soy protein is one of the most easily available biodegradable polymers. However there are some drawbacks such as low water resistance and mechan...

show abstract

“…reduce the flexibility of the film (Guerrero, Leceta, Peñalba, & Caba, 2014 (2007) and Coltro, Pitta, and Madaleno (2013) in that the addition of modified glycerol to the films could improve the TS…”

Section: Tensile Strengthmentioning

confidence: 99%

“…reduce the flexibility of the film (Guerrero, Leceta, Peñalba, & Caba, 2014 However, excess AA has the opposite effect, which may occur because at a higher AA content, it reduces the interactions between the protein chains, thus increasing the chain mobility and the association between the polypeptide chains of the SPI films. A greater addition of AA could reduce the interactions between the protein chains and increase the chain mobility and the association between the polypeptide chains of the SPI biocomposite films.…”

Section: Tensile Strengthmentioning

confidence: 99%

Mechanical property stability of soy protein isolate films plasticized by a biological glycerol‐based polyester and application in the preservation of fresh‐cut apples

Cao

et al. 2018

J Food Process Preserv

View full text Add to dashboard Cite

Soy protein isolate (SPI) film is a newly developed material used for packaging. However, its application has long been quite limited due to its poor mechanical property stability during storage. In our study, a biological glycerol‐based polyester (bio‐poly glycerol: adipic acid = 1:2 (BGP I), 1:1 (BGP II), and 2:1 (BGP III); w/w) is used as a plasticizer to enhance mechanical properties. These films were evaluated for tensile strength (TS), elongation at break (EB), water vapor permeability (WVP), moisture content (MC), glycerol emigration rate, oxygen permeability (OP), and contact angle (CA) and the morphologies of the films were visualized with a scanning electron microscope (SEM) and an atomic force microscope (AFM) for 60 days at 25°C. The TS of SPI‐BGP I, SPI‐BGP II, and SPI‐BGP III films increased by 12.94%, 18.22%, and 7.93%, respectively, and the EB increased by 23.63%, 37.27%, and 20.33%, respectively, compared to the films plasticized by glycerol. The stability of the WVP, MC, glycerol emigration rate, and OP of the films also increased, and a higher CA indicated a higher hydrophobicity in the films. The SEM and AFM images indicated that the films with BGP could form better cross‐links, so the inner structure of the film was still relatively complete and compact after storing for a period of time. The application experiments showed that the SPI‐BGP films had a good control effect on the browning reaction, effectively prohibiting the growth of microorganisms in fresh‐cut apples and extending the shelf life for at least 23 days compared to the control SPI films. Thus, the addition of a biological glycerol‐based polyester greatly broadens the applications for a SPI film. Practical applications The present study shows the mechanical property stability of SPI films plasticized by a BGP. The study also shows the application of BGP‐SPI films in the preservation of fresh‐cut apples. From the application point of view, this work could facilitate the application of SPI films on fresh‐cut fruits and various foods. Moreover, the study is helpful in understanding the cause and the mechanism of mechanical properties’ decline of SPI films during storage as well as providing help for other researchers in this field.

show abstract

Optical and mechanical properties of thin films based on proteins

Cited by 12 publications

References 8 publications

Endogenous Cu and Zn nanocluster-regulated soy protein isolate films: excellent hydrophobicity and flexibility

Endogenous Cu and Zn nanocluster-regulated soy protein isolate films: excellent hydrophobicity and flexibility

Soy Protein Based Green Composite: A Review

Mechanical property stability of soy protein isolate films plasticized by a biological glycerol‐based polyester and application in the preservation of fresh‐cut apples

Contact Info

Product

Resources

About