Development and Properties of Fish Gelatin/Oxidized Starch Double Network Film Catalyzed by Thermal Treatment and Schiff’ Base Reaction

Abstract

In order to improve the properties of fish gelatin (FG), oxidized starch (OS) was adopted to form hetero-covalent linkage with it based on thermal treatment and the Schiff' base reaction. The effects of different ratios of FG/OS (ranging from 10:1 to 2:1) on the properties of films were investigated. OS improved the mechanical and barrier properties of films significantly, while the moisture content decreased as OS concentration increased. The optimum concentration was obtained at the loading amount of 1.5% (w/v) OS. FT-IR spectra revealed the covalent cross-linking between FG and OS induced by Schiff' base reaction. Moreover, composite films had superior preservation effect on blueberry, according to the results of weight loss, total soluble solids, titratable acidity, and total anthocyanin content. Therefore, this study suggested that FG-OS double network films (FODF) has great potential in the packaging industry. that are maintained by physical effects, including electrostatic action, Van der Waals force, hydrogen bonding, etc. The combing process would be influenced by many parameters such as salts, temperature, and pH values. Compared to that, covalent bond has more permanent and firmer structure [7].Protein-polysaccharide conjugates could be obtained in different ways, such as Maillard reaction, enzymatic catalysis, etc. [8]. As a kind of non-enzymatic browning reactions, Maillard reaction can produce brown substances, [3], which would affect the aesthetics of the package. Enzymes such as laccase and peroxidase have been supplied to covalently cross-link proteins and hydrocolloids for a long time, but the cost should be enhanced to some extent [8].In the current research, fish gelatin (FG) and oxidized starch (OS) were supplied as the film forming substrates. Starch is a popular food material with good film forming properties, especially in consideration of cost, environment, and safety. [9]. However, previous studies have shown that the mixing of gelatin and starch results in the phase separation, which would affect the rheological, processing, and mechanical properties of the mixture [10]. Research showed that the compatibility of starch and gelatin can be improved by the oxidative modification of the starch to increase the content of the carboxyl and carbonyl groups in the starch. The cross-linking between OS and gelatin can improve the microstructure. [11].OS-FG interpenetrating and cross-linking network were successively fabricated by thermal treatment and Schiff' base reaction. The aldehyde groups in oxidized starch could crosslink with amino groups of gelatin by imine group (-C = N-) linkages and form hetero-covalent linkages polymers [12]. Figure S1 in Supplementary Materials illustrated the mechanism of Schiff' base reaction between gelation and oxidized starch. Thus, an improved understanding of the kinetics of the individually steps will lead to better possibilities for film formation with superior mechanical, barrier, and fresh-keeping performance.

3D-Printed Ginsenoside Rb1-Loaded Mesoporous Calcium Silicate/Calcium Sulfate Scaffolds for Inflammation Inhibition and Bone Regeneration

“…The infrared spectra were recorded in the wavelength range from 500 cm −1 –4000 cm −1 . The characteristic absorption band in the 1047 cm −1 region of the FTIR spectrum was related to the organic components (Si-O-Si) of the MSCS concentration [ 31 ]. With the addition of GR, there was a significant increase in FTIR spectra at the 1047 cm −1 and 1087 cm −1 region [ 25 ].…”

Effect of Bone Morphogenic Protein-2-Loaded Mesoporous Strontium Substitution Calcium Silicate/Recycled Fish Gelatin 3D Cell-Laden Scaffold for Bone Tissue Engineering

“…Besides, GelMa has been proven to be able to enhance in vitro osteogenic differentiation and calcium deposition as well as enhance in vivo endochondral bone formation [25]. In this study, we will use gelatin sourced from fish collagen provided from the recycling of an unutilized resource and successive high value-added products [26]. Results from our previous studies have shown that mesoporous calcium silicate scaffolds could be loaded with BMP-2.…”

Bidirectional Differentiation of Human-Derived Stem Cells Induced by Biomimetic Calcium Silicate-Reinforced Gelatin Methacrylate Bioink for Odontogenic Regeneration

“…FTIR was performed to further confirm the presence of CS in the GelMa and to characterize the interactions between the CS and GelMa. As shown in Figure 2B, CS10 had Si-O-Si, Si-O-Ca, and O-Si-O peaks at 1150, 1000, and 650 cm −1 , respectively, whilst CS0 had C-O, N-H, and C-N peaks at 1650, 1550, and 1250 cm −1 , respectively [29]. These results indicated that CS was successfully incorporated into the GelMa via a covalent bond and that different concentrations of CS were also successfully loaded, as seen from the difference in intensity in both CS5 and CS10.…”