Properties Of Gelatin Research Articles

Glycosylation with different saccharides on the gelling, rheological and structural properties of fish gelatin

In this study, the influence of glycosylation with κ-Carrageenan (κC), high methoxyl pectin (HMP), d-Galactose (Gal) on the gelling, rheological properties and mechanisms of fish gelatin (FG) were comparatively investigated. Results showed that κC was easiest to glycosylated with FG in comparison to HMP and Gal, also had the most significant improvement on the gelling properties and viscosity of FG. HMP was most difficult to glycosylated FG, but still had an excellent enhancement on viscosity. The results of intrinsic fluorescence, FTIR, X-Ray and SEM indicated that proper glycosylation changed the conformation structure and improved the contents of hydrogen bonds and α-helix, stabilizing the gels network. LC-MS/MS results showed that the main glycosylation sites were lysine and arginine amino groups, which was regarded as N-terminal glycosylation. In conclusion, proper N- glycosylation could significantly improve the gelling and rheological properties of FG. This study may provide a new guideline for modification FG to expand its application.

Gelatin extraction from chicken skin by conventional and Ohmic heating methods and comparison with commercial halal gelatins

Gelatin extraction from chicken skins using ohmic heating (OH) is a promising application in the food industry. In this study, the effects of OH parameters (electric field (5, 10, 15, and 20 V/cm) and extraction time (1, 3, and 5 h)) on the extraction yield, physicochemical, functional, rheological, thermal, and microstructural properties of chicken skin gelatin were investigated, as well as comparison with conventional extraction and commercial halal gelatins. Chicken skin gelatins obtained with OH-assisted extraction showed higher ash content resulting in more turbidity than commercial gelatins. OH parameters significantly increased the gelatin yield, and 1 h of OH treatment revealed the highest gel strength amongst the electric field applications, conventional extracted, and bovine gelatin. The melting and gelation temperatures of chicken skin gelatins were higher than bovine gelatin and OH treatment increased the thermal stability. The amino acid composition significantly changed with OH treatment, and total imino acid content, relating to the gelation properties, increased. Functional properties, water and oil binding, emulsifying, and foaming, of chicken skin gelatin were significantly higher than commercial gelatins, and OH treatment significantly increased these properties. Overall, OH extraction of gelatin from chicken skins could be a better option for less extraction time, higher extraction yield, better functionality, and higher thermal stability compared to conventional extraction. It was concluded that chicken skin gelatins extracted using OH have properties that can be an alternative to commercial gelatins, but further purification processes are required.

Underused Marine Resources: Sudden Properties of Cod Skin Gelatin Gel.

The main object of this work was to characterize the structure and properties of laboratory-made fish gelatin from cod skin in comparison with known commercial gelatins of fish and mammalian origin. This is one way we can contribute to the World Food Program and characterize foodstuff resources from alternative natural sources. Our research was based on the combination of an expanded set of complementary physical-chemical methods to study the similarities and distinctions of hydrogels from traditional and novel gelatin sources from underused marine resources. In this work, we have compared the morphology, supramolecular structure and colloid properties of two commercial (mammalian and fish) gelatins with gelatin we extracted from cold-water cod skin in laboratory conditions. The obtained results are novel, showing that our laboratory-produced fish gelatin is much closer to the mammalian one in terms of such parameters as thermal stability and strength of structural network under temperature alterations. Especially interesting are our experimental observations comparing both fish gelatins: it was shown that the laboratory-extracted cod gelatin is essentially more thermally stable compared to its commercial analogue, being even closer in its rheological properties to the mammalian one.

Insight into the mechanism of the decrease in mechanical strength and water-holding capacity of gels made from oxidized gelatin

The purpose of this study was to investigate the effect of oxidation on the physicochemical properties of gelatin and gelatin gels. Porcine skin gelatin was oxidized with different concentrations of H2O2 (0–30 mM). Upon oxidation of gelatin, a significant modification of amino acid residues including glycine, proline, hydroxyproline, and hydroxylysine occurred. Zeta-potential, ordered secondary structure and the fraction of triple-helix decreased, while particle size and surface hydrophobicity increased. Gels made from oxidized gelatin showed a looser network structure indicated by scanning electron microscope, and the gels had a weakened mechanical strength and water-holding as compared to non-oxidized gelatin gels. Based on these results, a mechanism of how oxidation affects the gelatin gel properties was proposed: Oxidation-induced increase of hydrophobicity and decrease of net charges promoted aggregation between gelatin molecules, thereby limiting the formation of triple-helix, which subsequently leads to a loose network structure and eventually a weakened gel strength and water-holding capacity.

Improvement of gelation properties of indica rice flour with stabilized rice bran from different thermal treatment

AbstractBackground and ObjectivesRice bran is enriched with bioactive compounds, which makes it more competitive as a functional food raw material. The stabilization of rice bran can inhibit the activity of endogenous enzymes, reduce its oxidation sensitivity, and change its physical and chemical properties, providing more possibilities for its application in the food industry. In this study, rice bran from five stabilization treatments (atmospheric pressure cooking, high‐pressure cooking, atmospheric steam, microwave heating, and extrusion cooking) were investigated for their effect on the gel properties of indica rice flour.FindingsStabilized rice bran could enhance the hydration properties and increase the enthalpy value of rice flour. The gelatinization properties indicated that the viscosity and fluidity of the rice paste were increased, and the aggregation and rearrangement of rice starch were promoted. From the rheological properties, stabilized rice bran enhanced the viscoelasticity of the rice flour gel. In addition, the stabilized rice bran could also reduce the yield of freeze‐thawing water of the rice flour gel. Rice bran with thermal treatments can significantly improve the gel properties of indica rice flour.ConclusionsIndica rice flour mixed with stabilized rice bran showed significant improvements in hydration, gelatinization, rheological properties, and freeze‐thaw stability.Significance and NoveltyIt is potential for the application of the gel from rice flour with stabilized rice bran in the starch‐based food industry.

Optimizing the making of modified plantain flour by the mixed-culture of lactic acid bacteria and yeast

Fermentation factors in the making of modified plantain flour must be optimized to obtain optimum conditions that produce the desired characteristics of flour/starch. In this research, we used mix-cultured lactic acid bacteria (LAB) and yeast for plantain fermentation. Response Surface Methodology (RSM) was used to explain the quantitative relationship between input and response variables. The design used is Combine D-optimal. The quantitative independent variables (X) selected were A = culture concentration (lower limit 2%; upper limit 6%) and B = fermentation time (lower limit 8 hours; upper limit 24 hours). Descriptive variables were C = type of plantain (C1 = “tanduk” plantain; C2 = “nangka” plantain) and D = type of culture (D1 = SC; D2 = LAB1 + LAB2; D3 = LAB1 + LAB3; D4 = LAB2 + LAB3; D5 = LAB1 + LAB1 + SC; D6 = LAB1 + LAB3 + SC; D7 = LAB2 + LAB3 + SC). Parameters of flour characteristic analyzed or response (Y) were carboxyl number (Y1), total acid (Y2), swelling number (Y3), pH (Y4), paste clarity (Y5), gelatinization properties: peak (Y6); trough 1 (Y7); breakdown (Y8); final viscosity (Y9); setback(Y10); peak time (Y11); pasting temperature (Y12), water content (Y13), color : *L (Y14); *a(Y15); *b (Y16) and c (Y17). The result showed that a combination of 6% culture concentration and 12.62 hours of fermentation time with a desirability value of 0.66 was the optimum condition with carboxyl value 0.15, total acid 0.47, swelling rate 13.49, peak time 5397.02, breakdown 2259.22, final viscosity 4125.22, setback 98.99, and dL 65.59.
 Keywords: modification flour, optimum condition, fermentation

Effect of molecular weight distributions on the gelation rate and other physicochemical properties of bovine bone gelatin (Type B)

The physicochemical properties of bovine bone gelatins (Type B) including amino acid and subunit compositions, gelation rate, Bloom values, viscosity, dynamic storage modulus (G’), gelling and melting temperature were investigated comparatively on the basis of molecular weight distributions (MWD). The MWD of gelatin was divided into three segments: >1000 kDa (H), 130 kDa–1000 kDa (M), and <130 kDa (L) for quantitative description and analysis. Results showed similar amino acid compositions for gelatins across different MWD. Gelatins with similar Bloom values exhibited different MWD, whose gelation rate increased with increasing segment H content and decreasing segment M and L content. Viscosity of gelatin was positively correlated with segment H content, and their gelling and melting temperature exhibited little difference. The present study suggests that increasing segment H content or decreasing segment M and L content in gelatin samples can increase the gelation rate and viscosity, making it suitable for 3D food printing.

Enzymes Immobilized into Starch- and Gelatin-Based Hydrogels: Properties and Application in Inhibition Assay.

The present work is a review of the research on using hydrogels based on natural biodegradable polymers, starch, and gelatin for enzyme immobilization. This review addresses the main properties of starch and gelatin that make them promising materials in biotechnology for producing enzyme preparations stable during use and storage and insensitive to chemical and physical impacts. The authors summarize their achievements in developing the preparations of enzymes immobilized in starch and gelatin gels and assess their activity, stability, and sensitivity for use as biorecognition elements of enzyme inhibition-based biosensors.

Novel cross-linking of toxic-free biopolymers for cellulose-gelatin films from avocado seed waste

Renewable, low-cost, and environmentally friendly processes have been continuously developed to produce biopolymers for various functional materials. This study aims to develop cellulose-gelatin film as a toxic-free biopolymer. Combining the excellent properties of cellulose and gelatin offers a promising alternative for improving the desirable properties. Herein, avocado seed waste was chemically treated and used as a cellulose-rich filler for gelatin-based film synthesis. Furthermore, different influences were examined with- and without- citric acid addition as a cross-linker agent. The citric acid cross-linked film has cellulose trapped in gelatin matrix structure with a smooth surface, good elasticity, sufficient flexibility, and free-toxic substance. Moreover, this study demonstrated that citric acid cross-linking design successfully improved the percent elongation film from 2.47 to 68.04 %, enhanced the water absorption capacity to 99.71 % at 24 h, and revealed high antibacterial activity, implying potential future application, especially for wound dressing.

Halal Alternative Sources of Gelatin: A Review

This article explores the growing interest in halal alternative sources of gelatin, driven by the need to provide suitable options for individuals adhering to Islamic laws. The overall methodology of this review involves a systematic examination using search engines from online databases, encompassing journals published from 2006 to 2023. The rationale for seeking alternatives beyond porcine gelatin is examined, considering religious and ethical considerations. Promising halal alternative sources are discussed, including animal-based gelatin, plant-based alternatives gelatin, aquatic animal-derived gelatin, microbial and fungal sources, as well as synthetic and recombinant gelatin. Each alternative is evaluated for its potential to meet halal requirements and applicability in various industries. The article also delves into the obstacles faced by the industry in adopting alternative gelatin sources, focusing on technological challenges and consumer acceptance. Technological challenges encompass replicating the functional properties of traditional gelatin, ensuring stability and shelf life, and addressing compatibility issues in diverse applications. Consumer acceptance and awareness pose challenges related to taste and texture perception, cultural and dietary preferences, and effective labelling and communication. Despite these challenges, the shift towards halal alternative sources of gelatin presents an opportunity for innovation in the food and pharmaceutical industries. It requires collaborative efforts between researchers, industry professionals, and regulatory bodies to overcome obstacles, ensure compliance with halal standards, and provide diverse consumer options following Islamic principles.

Enhancing physicochemical, antimicrobial, and release properties of fish skin gelatin films using dual-layer nanoparticles loaded with tea polyphenols/kojic acid for air-dried chicken preservation

This study investigated the effects of the physicochemical, antimicrobial and release properties of fish skin gelatin (FG) films by dual-layer nanoparticles containing tea polyphenols/kojic acid, and their application in air-dried chicken preservation. Dual-layer nanoparticles were prepared by layer-by-layer (LBL) self-assembly technique, yielding an average particle size of 365.4 nm. Atomic force microscopy confirmed the compatibility between the nanoparticles and the film matrix. Spectroscopic and X-ray analyses provided insights into hydrogen bond formation between the nanoparticles and the film matrix, supported by molecular docking studies, and the FG film with nanoparticles exhibited improved tensile strength, thermal stability, UV-blocking properties, and hydrophobicity. The composite film showed potent antimicrobial activity against spoilage bacteria, antioxidative effects, and controlled release behavior. In vitro toxicity tests confirmed the film's safety, which was then used to preserve air-dried chicken. High-throughput sequencing analysis indicated its effectiveness in suppressing spoilage bacteria like Brochothrix and Psychrobacter, influencing bacterial population distribution during storage. These findings hold strategic significance for improving active food packaging materials that incorporate food-derived nanoparticles into reinforced biofilms.

Improvement of Properties of Gelatinization and Retrogradation of Adzuki Bean Starch by Adding Glycolipid

To improve the storage quality of adzuki bean paste from starch aging, the effects of glycolipid addition on the properties of gelatinization and retrogradation properties of adzuki flour obtained by the retrogradation inside adzuki bean during storage and transportation are investigated. The results indicate the significant differences in the gelatinization and the distribution of starch granules for different varieties of beans. The higher gelatinization temperature of adzuki flour results in the lower enthalpy of gelatinization with an undulating tendency of the retrogradation due to the short-term aging of amylose and long-term aging of amylopectin within adzuki flour. In the early stage of aging, the coexistence of protein, fat, and starch inside adzuki flour hinder the aging of starch. An Avrami equation is introduced to characterize the aging process of the starch–protein–fat–water system of different varieties of adzuki flours. The nucleation mode of the crystal nucleus has a significant effect on the aging rate of different varieties of adzuki flour. The fat in the system fails to demonstrate a significant effect on the nucleation mode of starch retrogradation. The addition of glycolipids increases the gelatinization enthalpy of adzuki flour. Glycolipids can reduce the aging degree of adzuki flour, and the inhibition effect on the retrogradation of sucrose monoester is greater than that of maltose monoester. The research results provide the valuable guidance for the high-quality processing and storage of adzuki bean paste from starch aging.

Effect of non-starch components on the structural properties, physicochemical properties and in vitro digestibility of waxy highland barley starch

Highland barley (HB) endosperm with an amylose content of 0–10 % is called waxy HB (WHB). WHB is a naturally slow-digesting grain, and the interaction between its endogenous non-starch composition and the WHB starch (WHBS) has an important effect on starch digestion. This paper focuses on the mechanisms by which the components of β-glucan, proteins and lipids affect the molecular, granular, crystalline structure and digestive properties of WHBS. After eliminating the main nutrients except for starch, the estimated glycemic index (eGI) of the samples rose from 62.56 % to 92.93 %, and the rapidly digested starch content increased from 60.81 % to 98.56 %, respectively. The resistant starch (RS) content, in contrast, dropped from 38.61 % to 0.13 %. Comparatively to lipids, β-glucan and protein contributed more to the rise in eGI and decline in RS content. The crystalline characteristics of starch were enhanced in the decomposed samples. The samples' gelatinization properties improved, as did the order of the starch molecules. Protein and β-glucan form a dense matrix on the surface of WHBS particles to inhibit WHBS digestion. In summary, this study revealed the mechanism influencing the digestibility of WHBS from the perspective of endogenous non-starch composition and provided a theoretical basis to develop slow-digesting foods.

Discrepancies in resistant starch and starch physicochemical properties between rice mutants similar in high amylose content.

The content of resistant starch (RS) was considered positively correlated with the apparent amylose content (AAC). Here, we analyzed two Indica rice mutants, RS111 and Zhedagaozhi 1B, similar in high AAC and found that their RS content differed remarkably. RS111 had higher RS3 content but lower RS2 content than Zhedagaozhi 1B; correspondingly, cooked RS111 showed slower digestibility. RS111 had smaller irregular and oval starch granules when compared with Zhedagaozhi 1B and the wild type. Zhedagaozhi 1B showed a B-type starch pattern, different from RS111 and the wild type, which showed A-type starch. Meantime, RS111 had more fa and fb1 but less fb3 than Zhedagaozhi 1B. Both mutants showed decreased viscosity and swelling power when compared with the parents. RS111 had the lowest viscosity, and Zhedagaozhi 1B had the smallest swelling power. The different fine structures of amylopectin between RS111 and Zhedagaozhi 1B led to different starch types, gelatinization properties, paste viscosity, and digestibility. In addition to enhancing amylose content, modifications on amylopectin structure showed great potent in breeding rice with different RS2 and RS3 content, which could meet the increasing needs for various rice germplasms.

Improving gelling properties of fish gelatin by γ‐polyglutamic acid with four different molecular weights

SummaryThis work investigated gelling properties and structural characteristics of fish gelatin (FG) modified by four different molecular weights of γ‐polyglutamic acid (γ‐PGA) with 700, 1000, 2000 and 3000 kDa, respectively. Gelation‐melting transition temperature and gel strength increased with the increase of molecular weight in γ‐PGA. Especially, γ‐PGA in 3000 kDa made gel strength, gelation and melting temperatures reaching to 628.08 g (P &lt; 0.05), 22.30 °C and 30.17 °C (P &lt; 0.05), respectively. Non‐covalent interactions existed in FG and γ‐PGA. Such as, new hydrogen bonds were generated between them. Moreover, γ‐PGA with increased molecular weight enhanced three‐stranded helical structure and microscopic meshwork of FG. Finally, a schematic model was described to illustrate the interaction between FG and γ‐PGA in different molecular weights. On the whole, γ‐PGA with high molecular weight significantly improved gelling properties of FG, and could be a potential modifier of FG in the future.

Phase separation phenomena in gelatin-glucose syrup mixtures: Microstructures and gel characterization

This study delves into phase separation phenomena occurring within gelatin-glucose syrup (GS) mixtures, focusing on compositions ranging from 6 to 10% gelatin and 40–60% GS. The investigation employed 250 Bloom gelatins with distinct properties and GS with varying dextrose equivalence (DE). Microstructural analyses of mixtures were conducted using inverted fluorescent microscopy both immediately after blending at 80 °C and following a 24-h incubation at different temperatures. Visual observation as well as rheological, thermal and textural analyses were employed to monitor bulk phase separation occurring at 45 and 60 °C and gel properties upon cooling. Upon mixing, a diverse range of morphologies emerged, ranging from single-phase configurations to bicontinuous, protein-in-polysaccharide, and polysaccharide-in-protein arrangements, which was attributed to the immiscibility between gelatin and the DP10+ polysaccharides in the GS beyond a concentration threshold and potentially driven by the molecular ordering of gelatin and the shear forces during mixing. The miscibility of polymers and the nature of continuous phase were markedly influenced by the dosage and properties of gelatin (MW and pI) and GS (DE). During incubation at 60 or 45 °C, structural rearrangement occurred, with certain compositions undergoing substantial bulk separation. Rapid cooling effectively arrested the initial microstructures, giving rise to the formation of turbid gel networks. Comparative analysis of the gel properties indicated that GS generally promoted the formation of gelatin gels, but excessive addition of low DE GS proved counterproductive to proper gel development, resulting in the formation of soft, weakly structured gels prone to syneresis or even outright nongelation.

The impact of different concentrations of hyaluronic acid on the pasting and microstructural properties of corn starch

Starch aging in starchy foods is a major problem affecting their quality. In order to improve the viscosity and textural properties of native starch gelatinization and retrogradation, this study investigated the effect of hyaluronic acid (HA) at different concentrations (2 %, 4 %, 6 % w/w) on the pasting and microstructure of corn starch (CS). The findings revealed that the addition of HA significantly enhanced the peak viscosity, solubility, and water-holding capacity of the CS-HA mixtures. Moreover, it reduced the pasting temperature, swelling force, and leaching of amylose. All the mixtures exhibited shear thinning and thixotropic properties. The CS-HA mixtures created a thicker pseudoplastic system with significantly enhanced shear stability. The structures of the mixtures were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. It was observed that HA effectively inhibited short-term retrogradation of starch, enhanced the interaction between CS and HA, and formed a dense honeycomb three-dimensional mesh structure. In conclusion, as a novel anionic hydrocolloid, HA holds great potential to improve the retrogradation properties of starch-based products.

Engineering biodegradable controlled gelatin-zein bilayer film with improved mechanical strength and flexibility

Compiling hydrophobic and hydrophilic proteins to form mechanically reliable bilayer film with improved water barrier properties and hydrophobicity to replace petroleum-based standards is challenging because fabricating compatible surfaces and flexible film with interlinked interfaces is complex. The mechanical properties of gelatin and zein layers exhibited unique variations, and synergistic enhancement of bilayer properties reflected robust layer-by-layer (LBL) interactions. To overcome the problem of impaired integrated surface, viscously cross-linked zein film forming solution (FFS) by glyoxal (GX) introduced compact and closely entangled network formation with cross-linking of gelatin film. Zein surface compatibility and flexibility by GX and polyethylene glycol (PEG 400) synergized with the gelatin layer closed to compare flexible plastic materials such as PE and PP besides modulated color and transparency. Enhancing flexible formation was mechanized by acetic acid as solvent of zein solution after long-range repulsion during casting on well-manageable plasticized and cross-linked gelatin film with glutaraldehyde (GA) and PEG 400, respectively. Elongation (E%) was achieved by nearly 192% with modified tensile strength (TS) and Young's modulus (YM). Cross-linkers, especially GX, resulted in lower water solubility (WS), and joint layers resulted in controlled water vapor permeability (WVP) of bilayer films. Decreased surface roughness and WS increased water contact angle (WCA). FTIR spectroscopy, XRD analysis, DMTA, and SDS-PAGE analyzed cross-linking mode and intensity. Hence, gelatin-zein bilayer films showed significant potential for improving value-added functional properties.

Effect of formation of the maltodextrin/gelatin emulsion on gel properties of gelatin

This work investigated the influence of formation of the maltodextrin/gelatin emulsion on gel properties of gelatin. When the maltodextrin/gelatin emulsion was formed, adding maltodextrin increased the gelling temperature (Tg) but decreased the hardness of the gelatin gel. However, adding sucrose increased both the Tg and hardness, since no emulsion was formed. Thus, this work further investigated effects of the initial volume ratio of the gelatin and maltodextrin solutions (VGE/VMD), the dextrose equivalent (DE) of maltodextrin and the biopolymer concentrations on microstructure and properties of the emulsion gel. When the VGE/VMD was 3:7, 5:5, and 7:3, the Tg was 21.6, 24.6, and 23.8 °C, respectively, while the hardness was 365.2, 570.1, and 708.7 g, respectively. The droplet size decreased, as the VGE/VMD increased. These results suggested that smaller droplets induced a stronger emulsion gel. Similarly, maltodextrin of higher DE induced smaller droplets, lower Tg and larger hardness. Moreover, the gelatin concentration was positively correlated with the Tg and hardness but had no linear correlation with the droplet size, which suggested that more gelatin improved the gelling ability, and the emulsion gel strength depended on the gelling ability rather than the microstructure. Similarly, more maltodextrin induced higher Tg and hardness but bigger droplets.

Study on physicochemical properties and anti-aging mechanism of wheat starch by anionic polysaccharides

The anti-aging effects of two anionic polysaccharides AG (sodium alginate)/SSPS (soluble soybean polysaccharide) and WS (wheat starch) were evaluated, and their different mechanisms were explored. The rheological properties, gelatinization properties and aging properties were characterized. The addition of AG and SSPS changed the gelatinization parameters of WS, decreased the peak viscosity, breakdown viscosity and setback viscosity, and enhanced the fluidity of the gel system. Additionally, the starch molecular orderliness experiment showed that the relative crystallinity of starch gels decreased with the increase in AG and SSPS concentrations, indicating that the rearrangement of amylopectin was disturbed, which inhibited the cross-linking of starch molecules. The water state analysis showed that the hydrophilicity of AG and SSPS and their interactions with starch molecules influenced the relaxation behavior of water protons in the gel system in a concentration-dependent manner. In conclusion, the addition of AG and SSPS could significantly inhibit the aging of WS gels, probably due to the competition effect of AG and SSPS on water and the interaction with starch molecules. The present study results would provide new theoretical insights into WS-based food research.