Gelatin Films Research Articles

Comparison of fish and mammalian gelatin film properties: A meta-analysis

<abstract> <p>Edible films (EF) are continuously developed as food packaging alternatives due to their biodegradable properties. EF can be made from polysaccharides, proteins, lipids, and composite components. The use of raw materials certainly affects the properties of EF. Some studies reported that mammalian gelatin films were significantly different from fish gelatin films. However, there have been different results among individual studies. Therefore, the present study would like to obtain a valid conclusion across different studies using a meta-analysis approach. Study selection was performed with the PRISMA guideline. There were six relevant studies and 28 data used for meta-analysis. The statistical analysis was calculated by using Hedges*d. The results show that fish gelatin films had significantly lower (p < 0.05) tensile strength, elastic modulus, water vapor permeability, and transparency compared to mammalian gelatin films. Besides, there were two additional factors that are also discussed such as different film fabrication methods and gelatin concentration. Those seasonal factors were conducted by using subgroup analysis and meta-regression, respectively. The results described that the film production method, i.e., casting and compression molding significantly effect (p < 0.05) the tensile strength and elongation at break. Slightly different from the method, gelatin concentration was significantly affected (p < 0.05) the tensile strength, elongation at break, and water vapor permeability.</p> </abstract>

Eurytrema coelomaticum infection: correlation between parasite burden and impairment of pancreatic exocrine enzyme secretion

ABSTRACT: Eurytrema coelomaticum is a trematode reported in the pancreatic ducts of ruminants. It is conjectured that may cause disorders in the pancreas, as well as digestive and metabolic processes dependent on them. This study, determined if there is an impairment of exocrine pancreatic function, and correlated it with parasite burden. Pancreas, blood, and fecal samples were collected from 119 bovines at a abattoir. Stool samples were subjected to the gelatin and x-ray film digestion tests (to detect the presence of trypsin in feces). Using blood samples, the following biochemical tests were performed: amylase, lipase, glucose, fructosamine, cholesterol, triglycerides, total protein, albumin, and globulins. Analyses were correlated with pancreatic parasite burden. Cattle with a high parasitic load presented higher incidence of negative tests in both gelatin digestion and x-ray film digestion tests (P < 0.001) when compared to non-parasitized animals and those with a low parasitic load. Changes in those tests only occurred if the parasitemia was moderate or severe. The activity of the amylase and lipase enzymes was significantly higher in animals with low parasitemia (P < 0.05), compared to non-parasitized animals and with a high parasitic burden. In this study, in cases of high parasitemia, negative results were observed in both gelatin and x-ray film in the feces digestion tests. However, the low infection of E. coelomaticum, higher levels of serum amylase and lipase that also indicated loss of pancreatic exocrine functions were reported.

Gelatin-based composite films and their application in food packaging: A review

Gelatin is an important biopolymer that is extracted from collagen and is extensively used in the food industry because of its excellent functional properties. However, native gelatin films are moisture-sensitive and readily dissolve, swell, or split when they come in contact with water, which limits its use in food packaging. Various natural and synthetic materials are incorporated in gelatin films to improve their mechanical and thermal stability, elasticity, flexibility, and oxygen and light barrier properties. This review discusses various methods used for gelatin-based film production and modification approaches for improving their functional properties, including mechanical strength, thermal stability, water and light barrier ability, solubility and swelling, and antimicrobial properties. Moreover, gelatin-based films extend the shelf life of stored products due to their antioxidant and anti-microbial properties. The potential applications, challenges, and limitations of gelatin-based films in food packaging are also discussed. However, further research is required to prolong the modification of gelatin-based films using naturally available edible materials that are not commercially utilized. Further, studies about possible health hazards associated with the continuous use of gelatin-based packaging films should also be conducted in the future. • Various natural and synthetic materials are incorporated with gelatin to improve their properties. • Gelatin-based composites extend the shelf-life of food by reducing oxidation and microbial contamination. • The potential applications, challenges, and limitations of gelatin-based composites in food packaging were discussed.

Antimicrobial and antioxidant effect of lyophilized Fucus spiralis addition on gelatin film during refrigerated storage of mackerel

Lyophilized alga Fucus spiralis powder was incorporated into a gelatin-based film and employed as a packaging system for mackerel ( Scomber scombrus ) muscle portions throughout a 9-day refrigerated storage period at 4 °C. In global terms, a progressive loss of quality could be observed in fish muscle with increasing storage time. Comparisons between batches allowed us to conclude an inhibitory effect of F. spiralis -containing films on microbial activity (assessment of aerobes, psychrotrophs, and proteolytic bacteria) and on lipid hydrolysis (as determined by free fatty acid formation) in mackerel muscle. The presence of the lyophilized macroalga in the packaging film also led to a higher retention of primary (peroxides) and secondary (thiobarbituric acid reactive substances) lipid oxidation compounds, while the formation of fluorescent compounds (interaction compounds between lipid oxidation compounds and nucleophilic molecules present in the fish muscle) decreased. Both antimicrobial and antioxidant effects were more intense when the concentration of alga in the packaging film was increased. The preservative effect resulting from the presence of F. spiralis in gelatin-based films demonstrates the potential employment of such bioactive films to improve the retention of fish quality and enhance its commercial value. • Lyophilized Fucus spiralis was incorporated into a gelatin packaging film. • F. spiralis in the packaging film inhibited free fatty acid formation in mackerel. • F. spiralis inhibited aerobes, psychrotrophs, and proteolytic bacteria in fish muscle. • F. spiralis in the packaging film inhibited fluorescent compound formation. • Superior retention of primary and secondary lipid oxidation compounds was observed.

Improvement of Techno-Functional Characteristics of Fish Gelatin Films Using Peptide-Sugar Conjugates: Maillard Reaction Products

The effects of Maillard Reaction Products (MRPs) obtained from fish gelatin hydrolysates and D-glucose conjugation on the techno-functional characteristics of fish gelatin films were investigated, and the antioxidant effects were measured. MRPs were added to a gelatin solution at different concentrations (5-30% of the gelatin weight). The results revealed that the addition of the MRPs changed the film thickness from 0.15 mm (control) to 0.199 mm (film containing 30% MRPs). Some parameters including density, opacity, and color (ΔE) of the films were directly related to the MRPs concentration. Unlike these parameters, the solubility of the samples was not significantly altered, and the degree of swelling was indirectly changed owing to the MRPs addition. The results also indicated that the MRPs could dramatically decrease the water vapor permeability and oxygen permeability. The viscosity and mechanical properties of the films were increased as the MRPs concentration increased. The UV protective and the DPPH radical scavenging activities of the films were positively related to the MRPs concentration. The control sample (8.71 mg/mL) and the sample containing 30% MRPs (IC50 at 1.72 mg/mL) showed the lowest and highest antioxidant activities, respectively. The results of this study revealed that a fish gelatin film containing MRPs could be used as an active film in food packaging.

Effect of Crosslinking by Microbial Transglutaminase of Gelatin Films on Lysozyme Kinetics of Release in Food Simulants

Effect of Crosslinking by Microbial Transglutaminase of Gelatin Films on Lysozyme Kinetics of Release in Food Simulants

KaMin/Cadam agrees to buy BASF's kaolin business

Some physical and structural properties of gelatin films were studied as a function of glycerol content, focusing on the interactions between the glycerol, film structure and the moisture content. Fourier transform infrared spectroscopy was used to study the changes of the main functional groups of the film. The displacement in the amide's position occurred with lower plasticizer content, possible due to the predominance of bound water in the film matrix. The glycerol increased the flexibility of the films, as determined by the measurements of tensile strength, elongation and elastic modulus. Finally, microwave reflected signal measurements and dielectric constant measurements were also found to be sensitive to glycerol content, presumably due to its hydrophilic nature.

Fabrication and characterization of a pH-sensitive intelligent film incorporating dragon fruit skin extract.

A novel intelligent pH‐sensing indicator based on gelatin film and anthocyanin extracted from dragon fruit skin (Hylocereus polyrhizus) (DFSE) as a natural dye was developed to monitor food freshness by the casting method. Anthocyanin content of DFSE was 15.66 ± 1.59 mg/L. Dragon fruit bovine gelatin films were characterized by Fourier transform infrared spectroscopy (FTIR) and observed by a scanning electron microscope (SEM). Moisture content, mechanical properties, water solubility, water vapor permeability (WVP), light transmittance, color, and pH‐sensing evaluations were evaluated for potential application. FTIR spectroscopy revealed that the extracted anthocyanin could interact with the other film components through hydrogen bonds. When the extract was added, films showed a smooth and clear surface as observed by SEM. The addition of anthocyanin increased the moisture content, thickness, and water solubility of the films, but decreased the WVP and light transmittance of films. Also, the incorporation of 15% v/v DFSE decreased the tensile strength from 17.04 to 12.91 MPa, increasing the elongation at break from 91.19% to 107.86%. The films showed higher ΔE with increasing DFSE content, which indicated that the film had good color variability. A significant difference in the color of the films was observed with exposure to different pH buffer solutions. The findings demonstrated that gelatin film incorporated with DFSE could be used as a visual indicator of pH variations to monitor the freshness of foods during storage time.

Prevention of Protein Oxidation in Chicken Meat during Chilled Storage Using Chitosan Gelatin Films with Green Tea Extracts

In present study, the usability of chitosan and gelatin (1:1) films incorporated with green tea extract (GTE) to improve the shelf life of the chicken meat stored in chilled condition was evaluated. The extract of green tea was evaluated for its phenolic content, antioxidant activity and ferric ion chealating ability. The ChGel films possessed antimicrobial activity and inactivated approximately 3 log cfu/ ml of K. pneumoniae, S. typhi var. Weltevreden, S. typhi var. Oslo, Y. enterocolitica, E. feacalis, B. cereus, E. coli and S. aureus in 3 hours. Incorporation of GTE influenced the optical and mechanical properties of the films. Chicken samples without films were observed to be microbiologically safe for not more than 6 days, while ChGel and ChGel-GTE films improved the microbial safety of chicken samples till day 13. ChGel-GTE films also prevented lipid peroxidation in samples as evident by TBARS value (day 10: control: 1.14; ChGel-GTE: 0.21 mg MDA eq/kg). Protein oxidation during chilled storage of chicken was also prevented by ChGel-GTE by inhibiting protein carbonylation, loss of free thiols groups in protein and lowering the number of disulphde bonds. This study supports use of ChGel films with GTE for enhancing the safety of stored chicken meat not only by maintaining the microbial quality of the samples but also preventing oxidative changes which can hamper the functional, nutritional and sensorial properties.

Effectiveness of Goji Berries (Lycium barbarum) Extract and Some Nanoparticles Loaded on Gelatin Film on Microbial Content of Labneh

This study was conducted to evaluate the effect of Lycium barbarum extract, Chitosan nanoparticles (ChNPs) and Nanotitanium dioxide (TiO2 NPs) loaded on Gelatin films on the microbial content of labneh during different storage periods. The samples were divided into seven treatments which included (T1) non-coated labneh, (T2) labneh coated with gelatin membranes, (T3) labneh coated with gelatin membranes and Lycium barbarum extract, (T4) labneh coated with gelatin films and ChNPs, (T5) labneh coated with gelatin films treated TiO2NPs, (T6) Labneh coated with gelatin films, Lycium barbarum and ChNPs, (T7) Labneh coated with gelatin films, Lycium barbarum and TiO2 NPs. The total number of bacteria decreased after loading with the membranes for each specific period of time, and the treatment with T7 was the best, as the total number of bacteria decreased to 9.93 log/gm compared to the two controls (T1, T2), which amounted to (15.58, 13.47 log/gm) after 14 days of storage, respectively. While the numbers of Lipolytic and Proteolytic bacteria, yeasts and molds did not show any growth at the time of one day, with the prolonged storage period, the gradual increase in the total count of bacteria occurred for all treatments, it reached the highest numbers at the time of 14 days. Treatment T7 was the best in reducing the numbers of both lipolytic and proteinolytic bacteria, as well as yeasts and molds.

Effect of different dehydration methods on the properties of gelatin films

The properties of gelatin film fabricated by ethanol precipitation effect dehydration, Hofmeister effect dehydration and hot air drying dehydration were investigated. The results revealed that the mechanical properties were significantly improved by ethanol precipitation and Hofmeister effect. The tensile strength and elongation at break of the film prepared by ethanol precipitation were increased by 83.28% (20% gelatin concentration) and 122.42% (5% gelatin concentration) respectively compared with that of hot air-dried gelatin film. The water contact angle was increased and water solubility was reduced by ethanol precipitation, which could attribute to the formation of compact structure, more triple helix content, and non-covalent interactions. However, the water contact angle of Hofmeister effect fabricated films was decreased compared with that of hot air drying owing to the adhesion of ammonium sulfate. Moreover, ethanol precipitation effect improved the color difference and opacity due to the ethanol decolorization effect.

Performance of Gelatin Films Reinforced with Cloisite Na+ and Black Pepper Essential Oil Loaded Nanoemulsion.

The concern about consuming eco-friendly products has motivated research in the development of new materials. Therefore, films based on natural polymers have been used to replace traditional polymers. This study consists of a production of films based on gelatin reinforced with black pepper essential oil-loaded nanoemulsions and Cloisite Na+. The films were characterized by water vapor permeability, mechanical and thermal properties, surface contact angle, X-ray diffraction and scanning electron microscopy. It was observed that the films containing the nanoemulsion have higher permeability values and an increase in their mechanical resistance. The addition of nanoclay contributed to an increase in the surface hydrophobicity of the film and an increase in the tensile strength, at break, by about 150%. The addition of essential oil nanoemulsions led to an increase in thermal stability. The presence of clay dispersion contributed to the formation of a surface that was slightly rougher and grainier. The addition of the black pepper essential oil nanoemulsion resulted in an increase in porosity of the gelatin matrix. Through X-ray diffraction analysis, it was possible to conclude that both the polymeric gelatin matrix and the essential oils nanoemulsion are intercalated with the clay dispersion.

Characterization of glucose-crosslinked gelatin films reinforced with chitin nanowhiskers for active packaging development

To find renewable and sustainable alternatives to reduce the severe environmental impact of single-use synthetic plastic packaging, glucose-crosslinked gelatin films containing different amounts of chitin nanowhiskers (CNWs) were prepared. CNWs were first prepared by acid hydrolysis of chitin from shrimps, and characterized (morphological and thermal properties), before their addition into film-forming formulations. The films were heat-treated to promote the chemical crosslinking Maillard reaction (MR), between glucose and gelatin. The films then became less soluble (from 100% to ∼10%), thermally more stable, had a notably improved UV–vis light absorption capacity, and presented significantly enhanced tensile strength (from 42 to 77 MPa) and Young's modulus (from 1476 to 2921 MPa), however, they also became less flexible (from 17% to 7%) and transparent. These property alterations were mainly related to changes in crystallinity, the MR and to a lesser extent, to the formation of noncovalent (electrostatic and hydrogen bonding) interactions between CNWs and gelatin. Furthermore, due to the formation of MR products, the films turned yellow/dark brown and released antioxidant compounds (inhibition ∼33%) while immersed in water, which gave the films their active properties (stabilization of free radicals). These films have considerable potential as reinforced active packaging films for renewable food packaging applications.

Edible active film based on gelatin and Malpighia emarginata waste extract to inhibit lipid and protein oxidation in beef patties

Active gelatin-based films and extract from Malpighia emarginata (Acerola cherry) bagasse (ABE) were used to inhibit changes in the quality of beef patties during storage. Four treatments of gelatin-based active films were elaborated: edible film without ABE (EF), EF incorporated with 2% ABE (AF2), EF incorporated with 4% ABE (AF4) and EF incorporated with 6% ABE (AF6). Polyvinyl chloride (PVC) plastic film (PF) was used as a control. The active films showed adequate physical and barrier properties, being effective in controlling color changes and oxidation reactions in lipids and proteins present in the evaluated samples. The addition of ABE to the gelatin film demonstrated a positive effect up to a concentration of 4%. The AF4 treatment reduced the formation of malonaldehyde and total carbonyl compounds by 23.58 and 60.14%, respectively. Therefore, the use of active gelatin-based film and ABE appears to be a good strategy for prolonging the shelf life of frozen beef patties.

Synergistic effect of nano-ZnO and Mentha piperita essential oil on the moisture sorption isotherm, antibacterial activity, physicochemical, mechanical, and barrier properties of gelatin film

Synergistic effect of nano-ZnO and Mentha piperita essential oil on the moisture sorption isotherm, antibacterial activity, physicochemical, mechanical, and barrier properties of gelatin film

Green nanoarchitectonics with PEDOT:PSS–gelatin composite for moisture-responsive actuator and generator

With improvements in energy conversion efficiency and diversification of conversion manner, devices through natural evaporation from water reservoirs have potential to become an avenue to harvest energy. Using green, sustainable and biocompatible components is ever greater interesting for construction of humidity-induced actuator and generator. Here we demonstrate that green nanoarchitectonics with the bio-friendly poly(3, 4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)–gelatin have good mechanical and humidity responsive properties which can use to construct moisture-responsive actuator and generator. The PEDOT:PSS–gelatin film actuator is fabricated by simple spin-coating, in which PEDOT:PSS is introduced into natural gelatin to increase the mechanical intensity due to hydrogen bond and interpenetrated network between rigid PEDOT:PSS chains and protein molecules. The PEDOT:PSS–gelatin film combined with piezoelectric poly(vinylidene fluoride) (PVDF) film can be driven into the movement by humidity. The PEDOT:PSS–gelatin film and the driven PVDF film as actuator and generator generates piezoelectric signal. The bio-friendly evaporation-driven generator may have applications in self-powering biomedicine robotic system and sensors.

Facile Preparation of Antibacterial Gelatin-Kaolin Bionano- composite Membranes and Study of Water Sorption and Water Vapour Transmission Rate (WVTR)

Glutaraldehyde crosslinked gelatin kaolin bionanocomposite films were prepared by casting method and characterized by various techniques and water vapour transmission rates and water sorption studies were performed. The FTIR study revealed the interaction between functional groups of gelatin and kaolin evidenced by shifting of some spectral peaks. The grain size of bionanocomposite films was calculated to be 29 nm from XRD analysis and the crystallinity was 62 %. The SEM and AFM analysis suggested for heterogeneous surfaces having pores and pits. The glass transition temperature of gelatin film was found to increase from 70 to 100°C as revealed by DSC technique. The thermal properties increased with increasing kaolin. The addition of kaolin marked an increase in Young’s modulus and tensile strength. The bionanocomposite films showed a fall in water sorption capacity with increasing kaolin content. The water vapour transmission rate (WVTR) decreased with increasing addition of kaolin. The films were found to show antibacterial nature against Aureus.

Fully sustainable and high-performance fish gelatin-based triboelectric nanogenerator for wearable movement sensing and human-machine interaction

Triboelectric nanogenerators (TENGs) have been demonstrated promising as flexible, portable, and wearable devices in energy harvesting and self-powered sensing, providing a new possibility in wearable electronics and human-machine interaction. To reduce the environmental pollution, many sustainable and natural materials have been applied as friction materials in TENGs; however, it is still challenging to fabricate fully sustainable and high-performance TENGs, possibly due to the difficulty in choosing suitable sustainable friction pairs. Herein, we develop a general method to fabricate a flexible, transparent, fully sustainable, and high-performance fish gelatin-based TENG with its friction layers all composed of the fish gelatin films prepared from kitchen waste fish scales. These films can degrade completely within 30 days in the soil. Modifying the two friction layers with dopamine and fluorinated silane respectively to serve as a promising triboelectric pair, the obtained TENG shows remarkable output performances, which could be further enhanced via surface structuralization and dimension optimization. An open circuit voltage of 500 V and a short circuit current of 4 μA are realized, and the power density reaches up to 100 μW cm−2. To the best of our knowledge, the output voltage is much higher than that of the reported sustainable TENGs. Our fully sustainable TENG can directly light up 300 light-emitting diodes. Moreover, the device is also used in self-powered wearable sensing of human movements and in human-machine interaction. Our work demonstrates the great potential of utilizing the cost-efficient and sustainable fish scales in flexible, green, and wearable electronics, particularly in human-machine interaction.

Effect of Goji Berries (Lycium Barbarum) Extract and Some Nanoparticles Loaded on Gelatin Film in Chemical Properties of Labneh

This study is conducted to evaluate the effect of Lycium barbarum extract (Goji berries), Chitosan nanoparticle (ChNPs), titanium dioxide nanoparticle (TiO2 NPs) loaded on Gelatin films in terms of the chemical composition of labneh during different storage periods. The samples were divided into seven treatment procedures, include (T1) non-coated labneh, (T2) labneh coated with Gelatin membranes, (T3) labneh coated with Gelatin membranes and Lycium barbarum extract, (T4) labneh coated with Gelatin films and ChNPs, (T5) labneh coated with Gelatin films treated TiO2 NPs, (T6) Labneh coated with Gelatin films, Lycium barbarum, ChNPs, (T7) Labneh coated with Gelatin films, Lycium barbarum, TiO2 NPs. The results showed that the moisture percentage decreased significantly (p <0.05) untilthe end of the storage period, and treatment T6 was less in the rate of moisture loss (72.35%). It was also found that the ratios of protein, fat, ash, did not show significant differences at the time of one day compared with the two control samples T1 and T2, These percentages increased gradually as the duration of preservation was prolonged and reached their highest values at the time of 14 days. The pH values decreased significantly between (4.36-4.32) at the end of the storage period, compared with the two control samples T1 and T2, which were at 4.16 and 4.23, respectively. It was found that the fatty acid values of all treatments were significantly low compared with the control treatment T1 at the time of one dayThe free fatty acid ratios increased and reached their highest values between (0.29 - 0.32) for all treatments compared with the two control treatments T1 and T2 at the end of the storage period which amounted to (0.39 and 0.35) %.

Effect of carvacrol on properties and release behavior of gelatin‐egg white protein/polyethylene bilayer film

AbstractA bilayer antibacterial film of gelatin (G)—egg white protein (EW) containing carvacrol (CA) on polyethylene (PE) was prepared. This study investigated the effects of different concentrations of CA on the apparent viscosity and particle size of gelatin and egg white protein composite film‐forming solution (FFS). The static rheological results showed that the viscosity of FFS increased significantly in the presence of CA. The results of particle size showed that FFS had good stability. Fourier transform infrared (FTIR) spectroscopy indicated that there were hydrogen bond interactions among G/EW and CA with good compatibility. Scanning electron microscopy (SEM) indicated that the incorporation of CA made the film surface structure denser. The film with CA had good antioxidant and antibacterial activities. Under the same conditions, the higher the CA content, the higher the release rate, and the release rate was positively correlated with the increase in temperature and ethanol content in the food simulant, which indicated that the bilayer antibacterial film containing CA could be used for packaging high‐fat foods. Therefore, the G/EW‐PE bilayer antibacterial film containing CA could make up for the poor water resistance of the edible monolayer film, and gave the antibacterial function that the polyethylene packaging film did not have.Practical ApplicationsCA has safe and efficient antibacterial activity. It is listed by the Food and Drug Administration (FDA) in the list of additives that can be directly added to food for human consumption. Compared with the traditional single‐layer packaging film (plastic film and edible packaging film), the G/EW‐PE bilayer film containing CA can not only make up for the poor water resistance of the edible single‐layer film, but also give the plastic film new packaging performance. This study characterized the microstructure, physical properties, antibacterial properties and the release of CA in the film, which provided theoretical reference for the development of food packaging.