Gelatin Yield Research Articles

The extraction of gelatin from black tilapia fish skins with different acid concentration

Gelatin was extracted from black tilapia fish skins which is considered as one of the potential sources to produce gelatin. It’s mainly used in various food and pharmaceutical applications. The process of extraction gelatin was carried out via acid treatment at different concentration of 0.05 M, 0.1 M, 0.15 M and 0.2 M of hydrochloric acid (HCl) and followed by a final thermal extraction with water at 45°C. The objective of this study was to illustrate the effects of treated fish skins at different acid concentration to the properties in terms of yield, gel strength and moisture content for gelatin. The yield of gelatin for 0.05 M and 0.2 M were 18.86% to 20.95% respectively while for moisture content of gelatin were 6.93% to 8.34% respectively. The gel strength at 0.05 M gives the highest (290.8 g) which suitable as an edible gelatin.

Characteristics of Gelatin Produced Immersion of Tuna Bone in Lontar Vinegar from East Nusa Tenggara

By product of tuna processing industry can potentially be used as sources of high value gelatin products. Gelatin can be obtained from acid hydrolysis of collagen. East Nusa Tenggara is a producer of lontar vinegar, however the use of this vinegar for acid hydrolysis of collagen to produce gelatin has not been determined. This study aimed to evaluate the effect of lontar vinegar and the immersion time on the characteristics of gelatin. The research used complete randomized design with two factors: types of immersion solution and immersion period. The yield, moisture, ash content, pH and viscosity were observed. The results showed that the immersion solution did not affect significantly on the yield of gelatin. Meanwhile immersion time significantly affected the yield, moisture and pH of gelatin. Immersion of the tuna bones with 3% of lontar vinegar for six weeks produced gelatin with the best characteristics.<br /><br />

Effect of acid treatment on extraction yield and gel strength of gelatin from whiptail stingray (Dasyatis brevis) skin.

Chemical properties of fish gelatins differ from those of conventional mammalian sources, representing an attractive technological alternative for the food industry. Ray filleting generates a considerable amount of skin waste that can be used as a collagen source for gelatin extraction. Thus, this research evaluated the HCl and CH3COOH effect, at 0.01, 0.025, 0.05, 0.075, 0.1, 0.15, and 0.2M, on extraction yield, molecular weight distribution, and gel strength (GS) of whiptail stingray (Dasyatis brevis) skin gelatins. Results showed differences (P < 0.05) between acid type and concentration used. CH3COOH (0.15M) gave the highest extraction yield (7.0% vs. 5.5% at 0.15M HCl) and GS (653 ± 71g vs. 619.5 ± 82g at 0.2M HCl). Gelatin electrophoretic profile from CH3COOH revealed α-/β-components and high molecular weight (> 200kDa) polymers. Ray gelatin GS was higher than commercial bovine gelatin, suggesting its possible use for technological food applications.

Influence of spray-drying, freeze-drying and vacuum-drying on physicochemical and functional properties of gelatin from Labeo rohita swim bladder

Influence of different drying method on yield, physicochemical and functional properties of gelatin from rohu (Labeo rohita) swim bladder were investigated. Freeze-drying presented the highest gelatin yield (54.51 g/100 g, dry weight basis), followed by vacuum-drying (48.95 g/100 g) and spray-drying (41.76 g/100 g), respectively (P < 0.05). All gelatin samples showed glycine as the major amino acid followed by proline, glutamic acid, alanine, arginine and hydroxyproline, respectively. Freeze-dried gelatin (FDG) and spray-dried gelatin (SDG) showed α (α1 and α2), β-chains and γ-chain as the predominant components, whereas an absence of β- and γ-chains found in vacuum-dried gelatin (VDG). FTIR spectra revealed that the loss of the triple-helix was found in all gelatins which indicated the conversion of collagen to soluble gelatin. FDG and SDG had the highest surface hydrophobicity, protein solubility, emulsifying, foaming and gelation property than VDG (P < 0.05). Moreover, SDG showed slightly higher surface hydrophobicity, protein solubility, emulsifying and foaming properties as compared to FDG (P < 0.05). However, no significant difference was found in gelation properties of FDG and SDG (P > 0.05). Therefore, freeze-drying or spray-drying could be an appropriate drying method for preparation of gelatin from rohu swim bladder with better functionalities.

Characterization and Antioxidant and Angiotensin I-Converting Enzyme (ACE)-Inhibitory Activities of Gelatin Hydrolysates Prepared from Extrusion-Pretreated Milkfish (Chanos chanos) Scale.

Fish gelatin hydrolysates have been shown to possess various biological activities due to their unique Gly-Pro-Y and Gly-X-Hyp sequences. In the current study, fish gelatin was extracted from non-extruded milkfish scale (FSG1) or extrusion-pretreated milkfish scale (FSG2); extracted gelatins were hydrolyzed with different combinations of Flavourzyme and Alcalase to give four different hydrolysates, namely: FSGH1 (FSG1 hydrolyzed with Flavourzyme), FSGH2 (FSG1 hydrolyzed with Alcalase + Flavourzyme), FSGH3 (FSG2 hydrolyzed with Flavourzyme), and FSGH4 (FSG2 hydrolyzed with Alcalase + Flavourzyme). The extrusion-pretreatment process enhanced the extraction yield of gelatin from fish scale. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared (FTIR) analyses showed the extracts FSG1 and FSG2 possessed characteristics of gelatin. Moreover, the physicochemical characteristics of FSGH1–FSGH4 were examined by analyses of their degree of hydrolysis, amino acid composition, UV spectrum, FTIR spectrum, molecular weight, and RP-HPLC profile. Additional biological functional analyses showed that all of the studied gelatin hydrolysates FSGH1–FSGH4 possessed antioxidant activity dose-dependently as revealed by DPPH scavenging, ABTS scavenging, and reducing power analyses. In addition, FSGH2 and FSGH4 showed higher angiotensin-I-converting enzyme (ACE)-inhibitory activity as compared to FSGH1 and FSGH3. Taken together, FSGH2 and FSGH4 showed high antioxidant activity and potent anti-ACE activity. Due to the potential antioxidant and antihypertensive properties of FSGH2 and FSGH4, further research is needed to explore their possible use as natural supplementary raw materials in food and nutraceutical products.

Enhancement of Cell Adhesion, Cell Growth, Wound Healing, and Oxidative Protection by Gelatins Extracted from Extrusion-Pretreated Tilapia (Oreochromis sp.) Fish Scale.

Gelatin has been broadly utilized in the food, pharmaceutical, photographic, cosmetic and packaging industries, and there is also huge potential for novel applications of gelatin in the fields of biotechnology and biomedicine. In the present study, we extracted gelatin from fish processing waste, i.e., scale of tilapia, by a combined method of extrusion-pretreatment and hot water extraction. The extrusion-pretreatment process increases the extraction yield of gelatin. Three gelatins (FS2: preconditioning with double-distilled water (ddH2O) before extrusion; FS12: preconditioning with citric acid solution before extrusion; FS14: preconditioning with acetic acid solution before extrusion) were obtained and all of them enhanced cell adhesion, cell growth, and wound healing in HaCaT cells and protected HaCaT cells from H2O2-induced cellular damage. Among FS2, FS12, and FS14, FS12 exhibited the most pronounced enhancement of cell adhesion, cell growth, and wound healing in HaCaT cells, and thus it may have potential as an effective natural raw material in cell therapies for cutaneous wounds and for reducing H2O2-induced oxidative damage of cells. In additional experiments, it was found that phosphorylations of Akt and mTOR are involved in the signaling pathway activated by FS2, FS12, and FS14 in HaCaT cells.

Optimization of gelatin extraction from chicken mechanically deboned meat residue using alkaline pre-treatment

The purpose of this study was to optimize gelatin extraction from chicken MDM (mechanically deboned meat) residue using an alkaline pre-treatment. Experiments were conducted by using Central Composite Design of Response Surface Methodology (RSM). The independent factors such as NaOH concentration, extraction temperature and extraction time have been optimized to obtain chicken gelatins at different physicochemical and rheological characteristics. Extraction temperature and extraction time were found the most important factors affecting gelatin yield. On the other hand, NaOH concentration and extraction time were found the most important factors affecting gel strength. The optimum extraction conditions were determined as 2.9–3.4 g/100 ml NaOH concentration, 76°- 82 °C extraction temperature and 105–183 min of extraction time. Taken all together, the results showed that chicken MDM residues could be an alternative material for manufacturing chicken gelatin.

The physico-chemical properties of pangas catfish (Pangasius pangasius) skin gelatin

Gelatin can be used as emulsifier and stabilizer in food products. Until now, the most widely used raw materials for the production of gelatin industry are cow bone, cow skin and pig skin. Fish gelatin has been highlighted as a better alternative to replace mammals gelatin based on ethical and religious perspective. Fish gelatin was extracted from Pangas catfish skin to determine its physico-chemical properties. Different temperatures (45 °C, 50 °C, 55 °C) were employed during gelatin extraction. Higher temperature increased the yield and fat contents of Pangas catfish skin gelatin. In contrary, higher water, protein, ash contents were observed during lower temperature. Temperature significantly (p < 0.05) affected the gel strength, viscosity, melting point, and gelling point of fish skin gelatin. Based on the FTIR spectrum catfish skin gelatin functional groups can be identified as N-H, O-H, C = H, C-O and C-H.

Effects of Ultrasound Assisted Extraction in Conjugation with Aid of Actinidin on the Molecular and Physicochemical Properties of Bovine Hide Gelatin.

Actinidin was used to pretreat the bovine hide and ultrasonic wave (53 kHz and 500 W) was used for the time durations of 2, 4 and 6 h at 60 °C to extract gelatin samples (UA2, UA4 and UA6, respectively). Control (UAC) gelatin was extracted using ultrasound for 6 h at 60 °C without enzyme pretreatment. There was significant (p < 0.05) increase in gelatin yield as the time duration of ultrasound treatment increased with UA6 giving the highest yield of 19.65%. Gel strength and viscosity of UAC and UA6 extracted gelatin samples were 627.53 and 502.16 g and 16.33 and 15.60 mPa.s, respectively. Longer duration of ultrasound treatment increased amino acids content of the extracted gelatin and UAC exhibited the highest content of amino acids. Progressive degradation of polypeptide chains was observed in the protein pattern of the extracted gelatin as the time duration of ultrasound extraction increased. Fourier transform infrared (FTIR) spectroscopy depicted loss of molecular order and degradation in UA6. Scanning electron microscopy (SEM) revealed protein aggregation and network formation in the gelatin samples with increasing time of ultrasound treatment. The study indicated that ultrasound assisted gelatin extraction using actinidin exhibited high yield with good quality gelatin.

EFFECT OF ULTRASOUND ON PRETREATMENT OF TUNA SKIN FOR GELATIN PRODUCTION

This paper presents the result of study on the effect of ultrasound on extraction yield and quality of gelatin obtained from tuna skins using alkaline treatment method and alkaline-acid treatment method with ultrasound assistance. The results showed that ultrasound could shorten the time of alkaline treatment, while ensured the yield and the quality of obtained gelatin. Accordingly, the appropriate parameters of ultrasound mode that gave the best yield and quality of gelatin were determined as follows: for alkaline treatment method: amplitude of 80 %, period of 0.8s and ultrasound time of 90 min; for the alkaline-acid treatment method: amplitude of 8 0%, period of 0.8s and ultrasound time of 30 min. The former method produced gelatin with better yield and gel strength compared to the latter one (22.7 % and 143.3 g in comparison with 15.8 % và 122.4 g, respectively). The method with ultrasound support gave the gelatin with better quality in term of lipid content and gel strength in comparison with the traditional alkaline treatment method without ultrasound assistance.

Isolation of fish skin and bone gelatin from tilapia (Oreochromis niloticus): Response surface approach

In this study, gelatin from fish collagen, as one of halal sources, was extracted from tilapia (Oreochromis niloticus) skin and bone, by using Response Surface Methodology to optimize gelatin extraction conditions. Concentrations of alkaline NaOH and acid HCl, in the pretreatment process, and temperatures in extraction process were chosen as independent variables, while dependent variables were yield, gel strength, and emulsion activity index (EAI). The result of investigation showed that lower NaOH pretreatment concentrations provided proper pH extraction conditions which combine with higher extraction temperatures resulted in high gelatin yield. However, gelatin emulsion activity index increased proportionally to the decreased in NaOH concentrations and extraction temperatures. No significant effect of the three independent variables on the gelatin gel strength. RSM optimization process resulted in optimum gelatin extraction process conditions using alkaline NaOH concentration of 0.77 N, acid HCl of 0.59 N, and extraction temperature of 66.80 °C. The optimal solution formula had optimization targets of 94.38%.

Gelatin extraction from the indigenous Pangasius catfish bone using pineapple liquid waste

Gelatin extraction from fish bone has traditionally involved hydrogen chloride and/or sodium hydroxide during pre-treatment. However, these chemicals have begun to be abandoned because of their associated safety and environmental issues. Several studies have looked at the use of citric acid as a safer alternative in fish bone gelatin extraction. The aim of this research was to extract gelatin from the bone of Pangasius catfish with pineapple liquid waste. The extraction was performed in two steps: pre-treatment followed by main extraction at various times (24–56 h) and temperatures (45–75°C). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used as a confirmation test and showed a band for gelatin at ~120 kDa. Gelatin yields were calculated as the ratio of weight of dried gelatin to the total weight of fish ossein. The results indicated that pineapple liquid waste can be used for fish bone gelatin extraction. The recommended conditions for extraction of fish bone gelatin using pineapple liquid waste are 56 h of pre-treatment and 5 h of main extraction at a temperature of 75°C. The gelatin yield was 6.12% and the protein concentration 4.00 g/100 g.

Characterization of gelatin from bovine skin extracted using ultrasound subsequent to bromelain pretreatment

Bovine skin was pretreated with bromelain enzyme and ultrasound (53 kHz and 500 W) was used to extract gelatin for the time durations of 2, 4 and 6 h at 60 °C (samples were referred as UB2, UB4 and UB6, respectively). Control (UBC) gelatin was extracted using ultrasound for 6 h at 60 °C without enzymatic pretreatment. Gelatin yield increased significantly (P < 0.05) as the time duration of ultrasound treatment increased with UB6 giving the highest yield of 19.71% followed by UBC (18.67%). Gel strength and viscosity of UBC were 603.24 g and 16.33 mPa s, respectively. The corresponding values for UB6 were 595.51 g and 16.37 mPa s, respectively. The amino acids content increased with longer duration of ultrasonic treatment and UBC exhibited the highest content of the glycine (27.06%) and hydroxyproline (17.21%) compared to other samples. Protein pattern of the gelatin samples showed the progressive degradation of polypeptide chains as the time duration of ultrasound extraction increased. As demonstrated by Fourier transform infrared (FTIR) spectroscopy, amide I band of gelatins extracted by ultrasound treatment exhibited higher wavenumbers than the commercial gelatin (CG) suggesting greater loss of molecular order in these samples. Longer duration of ultrasonic treatment resulted in denser, irregular, disorganized and more interconnected structure with increased porosity as revealed by scanning electron microscopy (SEM) but structural integrity was retained in UBC indicating degradation effect of bromelain enzyme in other samples. Finally, it was concluded that the ultrasound assisted gelatin extraction using bromelain enzyme produced high yield with good quality gelatin.

Gelatin characteristics of Bali cattle skin protein extract on acetic acid concentration and different length of curing

Gelatin Production of Bali cattle skin protein extract is an alternative to obtain permitted gelatin. The objective of the research was to know the effect of concentration and different acetic acid curing time to gelatin characteristic of the animal skin and to determine the best of the characteristic. Indicators of them were pH value, the yield of gelatin, moisture content, protein, fat, viscosity and gel strength. The extraction of Bali cattle skin protein was conducted with curing for 2; 4; and 6 days and acetic acid on concentration 2%; 4%; 6% and 8%. Statistical analyzed showed that increase of acetic acid concentration and curing time and its interaction was significant (P<0.05) affected the quality of the animal skin gelatin. Index of effectiveness showed that the best treatments combination was on acetic acid concentration 8% and curing time 6 days (A4C3) in produced gelatin. Indicator of quality were yield of gelatin (11.91%); water concentration (10%); protein (88.13%); fat (0.98%) and viscosity (5.35 cP). It can be concluded that the increase of acetic acid concentration and curing time affected quantity and quality of the animal skin gelatin.

Effect of extraction temperature on characteristics of chicken legskin gelatin

Gelatin is a denaturalized protein that is derived from collagen by acidic or alkaline hydrolysis and is an important functional biopolymer that has a very broad application in many industrial fields. Its functional properties depend on processing conditions as well as the raw material. The objective of the research was to study effect of extraction temperature on characteristics of native chicken legskin gelatin. This study used Completely Randomized Design (CRD) with four treatments (T1 = 500C, T2 = 550C, T3 = 600C, T4 = 650C) and five replications. Statistical analysis were carried out by one Anova and the mean difference was tested using Duncan’s Multiple Range Test. The result of research indicated that, extraction temperature had significant effect (P<0.05) on yield, gel strength, viscocity and protein content of chicken legskin gelatin, but it had no significant effect (P>0.05) on water content. It was concluded that the use of extraction temperature 600C was (yields 13.75, gel strength 78.75 g bloom, viscosity 6.52 cP, protein content 84.23% and water content 6.20%).

Optimization and characterization of gelatin and chitosan extracted from fish and shrimp waste

Fish and seafood processing industries generate large quantities of waste which are at the origin of several environmental, economic and social problems. However fish waste could contain high value-added substances such as biopolymers. This work focuses on optimizing the gelatin and chitosan extraction from tilapia fish skins and shrimp shells respectively. The gelatin extraction process was optimized using alkali acid treatment prior to thermal hydrolysis. Three different acids were tested at different concentrations. Chitosan was obtained after acid demineralization followed by simultaneous hydrothermal deproteinization and deacetylation by an alkali treatment with different concentrations of HCl and NaOH. The extracted gelatin and chitosan with the highest yield were characterized by determining their main physicochemical properties (Degree of deacetylation, viscosity, pH, moisture and ash content). Results show a significant influence of the acid type and concentration on the extraction yield of gelatin and chitosan, with an average yield of 12.24% and 3.85% respectively. Furthermore, the obtained physicochemical properties of both extracted gelatin and chitosan were within the recommended standard values of the commercial ones used in the industry.

Research on rapid gelatinization of rabbit skin collagen as effect of acid treatment

In this study, the mechanism of rapid gelatinization of rabbit skin collagen was examined. Yield and gel strength of gelatin extracted from rabbit skin reached (60.02 ± 2.50)% and (439 ± 17)g, respectively, via pretreatment for 5 min with 1% (w/v) HCl. The results of gelatin extracted from purified rabbit skin collagen demonstrated that a short-term acid pretreatment will cause obvious cleaning loss. SDS-PAGE analysis revealed that the covalent bonds in rabbit skin collagen are easily destroyed by acid, initially destroying the covalent cross-linking between collagen molecules and covalent bonds in a non-helix crystallization. Only when the subunits are exposed will the peptide bonds be destroyed. Analysis of FTIR and SEM suggested that acid pretreatment destroyed the original spatial structure of collagen in a short period of time. Meanwhile, the collagen took on the appearance of orderly wavy folds. As the acid pretreatment continues, the gelatinized collagen will form a new conformation through new hydrogen bonding, and its surface folds became smaller.

Extraction and physicochemical characterization of broiler (Gallus gallus domesticus) skin gelatin compared to commercial bovine gelatin

Gelatin was extracted from broiler (Gallus gallus domesticus) skins and analyzed to compare its physicochemical properties with those of commercial bovine gelatin. The average yield of broiler skin gelatin was 6.5% on a wet weight basis. Broiler skin gelatin had more α1-and α2-chains than β- chain and contained high molecular weight (γ- chain) polymers. Glycine was the dominant amino acid in broiler skin gelatin (20.26%), followed by proline (Pro) (15.12%) then hydroxyproline (Hyp) (11.36%). Compared to commercial bovine gelatin, broiler skin gelatin had less total imino acids (Pro and Hyp) but a higher (33.65 vs. 31.38°C) melting temperature (P < 0.01). The differences in physical properties between the broiler and commercial bovine gelatins appeared to be associated with differences in their amino acid composition and molecular weight distribution. The sensory evaluation results revealed that broiler skin gelatin could be a potential alternative to commercial bovine gelatin, useful in various food products.

Characteristics and Physicochemical Properties of Gelatin Extracted from Scales of Seabass (Lates calcarifer) and Grey Mullet (Mugil cephalus) in Vietnam

ABSTRACTIn this study, gelatin was obtained from the scales of seabass (Lates calcarifer) and grey mullet (Mugil cephalus) collected in Vietnam by using Alcalase® 2.4 L FG for pretreatment and electrochemically activated water with pH 2.0–2.5 for extraction. The characteristics and physicochemical properties of gelatin were investigated. The results indicated that the gelatin had a high protein content (88.6–90.0%) with ash (1.43–1.55%) and no fat. The gelatin was identified as type A due to its pH value. The yields of gelatin were 14.1–15.2%. The gel strength and melting point were 270.3 g and 26.7°C, respectively, for gelatin from seabass scales and 249.1 g and 25.9°C, respectively, for samples from grey mullet scales. In contrast, the viscosities of gelatin were found to be 6.97 cP for seabass and 8.73 cP for grey mullet. Both gelatins contained α-chain and β-chain as the major components. Circular dichroism spectra indicated that the triple helical structure in collagen was almost transformed to the random coil structure in gelatin. The proportion of imino acids was high (197–205 residues/1,000 residues). So, gelatin from seabass and grey mullet scales could be used as a potential replacement for mammalian gelatin.

Physico-chemical and functional properties of gelatin from Surimi processing byproducts (Refiner discharge)

Surimi processing industries generate large quantities of waste of which refiner discharge is of one kind. Gelatin extraction from such waste has not been attempted widely. Gelatin was extracted from pink perch ( Nemipterus japonicas ) surimi refiner discharge and its physico-chemical and functional properties were studied. The gelatin yield was 15.86 % on dry weight basis. The bloom strength, viscosity and melting point of the refiner discharge gelatin were recorded as 147.9 g, 7.44 cP and 25.5°C, respectively. The refiner discharge gelatin is rich in glycine followed by glutamic acid, proline and alanine. The gelatin has high intensity of β- and α-chains as the major components. Emulsifying capacity and emulsion stability of gelatin were 50.77% and 50.44%, respectively; indicating the extracted gelatin from refiner discharge had strong emulsion stability. The refiner discharge gelatin was also found to have good foam expansion of 38.45 %. It can be concluded from the present study that fish surimi refiner discharge can be a potential source for gelatin production. Byproducts like refiner discharge have added advantage of avoiding the seggration problem of solid waste into skins, scale and bones before the extraction of gelatin.