Gelatin Yield Research Articles

Extraction and characterization of gelatin from bovine heart

Abstract The objective of this study was to investigate the effects of initial heat extraction time and enzyme concentration during subsequent pepsin digestion on gelatin quality from bovine heart (BH) connective tissue (CT). BH gelatin was extracted from isolated BH CT at 80 °C for 4 or 6 h. Gelatin remaining in the CT residue was extracted with pepsin at either 100 or 200 mg pepsin/g CT to examine the yield and properties of enzyme-extracted gelatin. BH gelatins extracted at 80 °C showed very good gel strength (241–269 g) compared to that subsequently extracted with pepsin (54–96 g) and gelatin yield increased with the length of heat extraction (3%) although gel strength was reduced. Heat-extracted BH gelatin regardless of duration of heat extraction contained α1 and α2 chain as main components with some degradation peptides. The frequency sweep test of BH gelatins showed independency in a wide range of frequency (1–196 Hz) regardless of whether extracted by heat or pepsin. Heat-extracted BH gelatins exhibited the highest storage modulus values (1165–1245 pa). BH gelatins extracted with the lowest concentration of pepsin showed a higher mean storage modulus value than gelatin extracted with the highest pepsin concentration. The present study is the first to demonstrate that gelatin extracted from BH collagen using heat and pepsin has characteristics comparable to other sources of gelatin, making it suitable for many applications, and confirms that the use of pepsin increases BH gelatin yield with a concomitant reduction in gelatin quality.

Extraction of gelatin from salmon (Salmo salar) fish skin using trypsin-aided process: optimization by Plackett-Burman and response surface methodological approaches.

Gelatin from salmon (Salmo salar) skin with high molecular weight protein chains (α-chains) was extracted using trypsin-aided process. Response surface methodology was used to optimise the extraction parameters. Yield, hydroxyproline content and protein electrophoretic profile via sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of gelatin were used as responses in the optimization study. The optimum conditions were determined as: trypsin concentration at 1.49U/g; extraction temperature at 45°C; and extraction time at 6h 16min. This response surface optimized model was significant and produced an experimental value (202.04±8.64%) in good agreement with the predicted value (204.19%). Twofold higher yields of gelatin with high molecular weight protein chains were achieved in the optimized process with trypsin treatment when compared to the process without trypsin.

Effect of various acids on physicochemical and functional characteristics of gelatin from swim bladder of rohu (Labeo rohita).

Influence of various acids (acetic acid, phosphoric acid, and propionic acid) at different concentrations (0.05, 0.1, and 0.2M) on the extraction yield, physicochemical and functional properties of gelatin from Labeo rohita swim bladder were investigated. Highest gelatin yield (44.22%, dry weight basis) was obtained in a sample prepared by without acid pretreatment (GWA) of swim bladder as compared to acid pretreatment counterparts. Amongst the acid pretreatments, propionic acid (GPrA) showed the highest gelatin yield, followed by acetic acid (GAA) and phosphoric acid (GPA) at all concentrations used, respectively. Moreover, with increased concentrations of all acids, the decrease in gelatin yield was observed for all the acids. GWA showed higher protein and hydroxyproline content than that of acid counterparts (P<0.05). Amino acid analysis of gelatins showed glycine as the major amino acid in all gelatins followed by proline, glutamic acid and alanine, respectively. GWA showed α (α1 and α2) and β-chains as the predominant components with low molecular weight peptides. However, GPrA, GAA, and GPA had α1 and α2 dominant constituents. FTIR spectra of gelatins revealed that the loss of the triple-helix was found in GPA, GAA, and GPrA, compared to GWA. Among gelatin samples, GWA showed the highest solubility at all pH tested followed by GPrA, GPA, and GAA respectively. Furthermore, GWA exhibited higher emulsifying, foaming and gelling properties as compared to GPrA, GPA, and GAA, respectively. Therefore, the acid pretreatment of swim bladder had a negative impact on the extraction yield, physicochemical and functional properties of gelatin from rohu swim bladder.

Characteristics and Gel Properties of Gelatin from Skin of Asian Bullfrog (Rana tigerina)

Characteristics and gel properties of gelatin from frog skin as influenced by extraction temperatures (45–75 °C) were investigated. Yield of gelatin increased as the extraction temperature increased (P 0.05). Gelling and melting temperatures of frog skin gelatin were 23.47–24.87 and 33.22–34.66 °C, respectively. Gels became more yellowish with increasing extraction temperatures (P < 0.05). All gelatin gels were sponge or coral-like in structure but varied in patterns as visualized by scanning electron microscopy (SEM). Gelatin from frog skin could be used as a replacement for land animal counterpart.

Yield and Gel Strength of Gelatin Extracted from Smoked Salmon (Salmo salar) Skins

ABSTRACTThe gelatin yield and gel strength of gelatin extracted from the skins of smoked salmon were determined. The skins had a crude protein content of 43.5 ± 1.2% and an estimated collagen content of 23.6 ± 1.0%. Following an alkali extraction process under varying extraction conditions, the protein content varied from 2.78% to 32.1%, and the gelatin yield ranged from 2.23% to 22.4% of the initial skin weight. The gelatin purity (gelatin/protein) ranged from 55.4% to 100%, with the highest Hyp/protein sample arbitrarily designated as being 100% pure, i.e., an assumption of pure gelatin. Statistical analysis showed that HCl concentration, pretreatment temperature, and extraction temperature significantly affected the protein yield and gelatin yield. The wide range of gel strengths indicates that the gelatin might have been hydrolyzed to different extents during the different extraction and cooling processes. Statistical analysis did not show that any of the factors studied affected the gel strength. However, the data indicated that low NaOH concentrations and HCl concentrations might not prevent hydrolysis during the extraction process. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS–PAGE) showed that the gelatins contained α- and β-chains and that the gelatins composed of higher concentrations of larger molecular weight polypeptide chains had higher gel strengths.

Structural characteristics of camel-bone gelatin by demineralization and extraction

ABSTRACTCamel bone was demineralized through HCl acidulation process at different concentrations (0.0%, 1.5%, 3.0%, and 6.0%) over 1–5 days. The level of demineralization was acid concentration and soaking time dependent. Highest demineralization (62.0%) was recorded in bone sample treated with 6.0% dilute acid for 5 days. Energy dispersive X-ray spectroscopy (EDX) elemental analysis revealed reduction in Ca and increase in N and H, while O remains unaffected. Particulate characteristics by scanning electron microscope showed an increased surface roughness of bone after demineralization. Fourier transform infrared (FT-IR) analysis of ossein depicted the presence of functional group similar to that of bone protein (collagen). Statistical optimization by central composite design (CCD) revealed a significant quadratic model for optimum values of extraction temperature, pH, and extraction time. The highest gelatin yield from camel bone was 23.66% at optimum extraction condition (71.87°C, pH 5.26, and 2.58 h) and the bloom was 205.74 g. Camel bone is suitable for production of gelatin with good potentials in food and nonfood applications.

Influence of Extraction Process (Pre-Treatment Time) on the Characteristic of Black Tilapia Fish Skins Gelatin

Gelatin from black tilapia skins are one of the propose alternative sources for various applications especially in food and pharmaceutical industries. The extraction process of gelatin from black tilapia skin was carried out by using 0.03 M of hydrochloric acid (HCl) with different pre-treatment times (4 h, 16 h and 24 h) and followed by a final extraction with water at 45°C and 65°C . Thus, this study explores the effects of pre-treatment time to the yield and moisture content of gelatin. The highest yield have been recorded about 22.48% and 21.5% while moisture content were 5.63% and 44.25% for both extracted temperatures (45°C and 65°C) respectively that treated for 4 h. Fourier Transform Infrared Spectroscopy (FTIR) has been used to analyse the interactions and characteristics between functional groups of the gelatin.

The effect of pretreatment using hydrochloric acid on the characteristics of buffalo hide gelatin

The objective of the research was to identify the effect of the concentration of hydrochloric acid (HCl) on yield and the characteristics of gelatin from buffalo hide. A completely randomized design was used with various concentrations of HCl treatment 0.3M, 0.6M, 0.9 M, 1.2 M and 1.5M, and four times replication, followed by least significant difference test. The HCl concentration gave significantly effect (P&lt;0.05) on yield, viscosity, pH, gel strength and redness of gelatin. The highest yield (29.17%) was obtained at a concentration of HCl 0.9M. The highest gel strength and viscosity at concentration of 1.2M, were 293.41g bloom and 22.17 cp, respectively. The pH of the gelatin were 5.08 to 5.52. The lightness level (L*) was 69.92-70.97, whereas the redness ranged (a*) from 0.55 to 1.54 and the yellowness ranged (b*) from 17.54 to 19.59. The moisture, protein and ash concentrations of gelatin were 7.05±0.07-8.92±0.06%, protein content of 83.38±0.06 -91.11±0.03%, and the ash content 0.53 ± 0.04 to 1.23 ± 0.09%, respectively. Based on the spectra absorption of infrared were detected four areas amides: amide A (3402.43-3448.72 cm-1), amide I (1635.65 cm-1), amide II (1527.62 cm-1) and amide III (1242.16 cm-1). The differences in the concentration of HCl had impact on yield,characteristics and secondary structure of buffalo hide gelatin. The HCl concentration at 0.9M was the optimum condition to obtain the highest yield. The characteristics of buffalo hide gelatin after pretreatment using hydrochloric acid had met the standards of GMIA (2012).

Extraction and Characterization of Gelatin from Bovine Lung

Gelatin is extracted from animal tissues using heat usually with low yields, but pepsin may increase high quality gelatin yield per unit of tissue. Gelatin from bovine lungs was extracted using heat and pepsin and the resulting gelatins were characterized. Pepsin increased gelatin yield by about 9-fold that of heat extraction alone. All bovine lung gelatin contained protein as the major proximate component, with little ash and non-detectable fat. Bovine lung gelatin had pH, moisture and protein comparable to or less than that of commercial bovine gelatin and decreased ash. Transmittance of bovine lung gelatin was substantially reduced compared to that of commercial bovine gelatin but had increased water and fat-binding capacity, and comparable or increased gelling and melting temperature. Gel strengths of bovine lung gelatin were comparable to or lower than and foam stability and emulsifying activity were lower than commercial bovine gelatin. Increased imino acid (proline and hydroxyproline) content was associated with increased gelling and melting temperatures and was comparable to commercial bovine gelatin. Heat-extracted bovine lung gelatin contained predominantly collagen γ– chains, β– chains and α– chains (α1(I) and α2(I)), with some low molecular weight peptides, while the pepsin-extracted lung gelatins were characterized by comparatively decreased β– and α– chains and increased low molecular weight peptides. The gel strength of heat-extracted bovine lung gelatin was higher than that of pepsin-extracted gelatins, indicating that additional yield was associated with reduced gelatin quality. Bovine lung is a potential source of gelatin for application in diversified industrial fields and use of pepsin is a viable method for extracting additional gelatin after heat extraction of high quality (increased gel strength) gelatin from bovine lung.

Characteristics and Properties of Gelatin from Seabass (Lates calcarifer) Swim Bladder : Impact of Extraction Temperatures

This study aimed to investigate the impact of various extracting temperatures on yield and properties of gelatin from swim bladder of seabass (Lates calcarifer), a byproduct from processing. Gelatin from seabass swim bladderwas extracted at different temperatures (45, 55, 65 and 75 °C). The gelatins obtained using various extraction temperatures were characterized. The yield and recovery of gelatin from swim bladder (44.83–71.95% and 49.08–74.83%, based on dry weight) increased with increasing extraction temperatures. All gelatins contained α-chains as the predominant components, followed by β-chain. Gelatin from seabass swim bladder showed a high imino acid content (195 residues/1000 residues). FTIR and CD spectra revealed the loss of triple helix during heating via breaking down hydrogen bonds between α-chains. Gel strength generally increased as the extraction temperature increased up to 65 °C (P < 0.05). Gelatin extracted at 65 °C for 6 h showed a higher gel strength, compared to bovine gelatin (P < 0.05). Gelling and melting temperatures were 10.4–19.7 and 19.3–28.4 °C, respectively, depending on extraction temperature. Properties of gelatin from swim bladder were affected by extraction temperature. Therefore, seabass swim bladder could serve as an alternative collagenous material for gelatin production, when the appropriate extraction condition was implemented.

Isotopic comparison of gelatin extracted from bone powder with that from bone chunk and development of a framework for comparison of different extraction methods

Stable isotope analysis of collagen extracted from ancient bones has become a routine exercise. Collagen can be extracted from either bone powder or chunks, but little research has compared these two procedures in detail. In this study, yield, elemental concentration, and carbon and nitrogen stable isotope ratios of gelatin extracted from bone powder or chunks were compared, and a new framework to compare the quality of gelatin samples extracted from identical bone samples using different extraction methods was presented. Forty adult human skeletons from two sites in Japan dating from the Edo period (1603–1867CE) were used. In the “chunk method,” bone chunks are demineralized, gelatinized, and filtered to obtain gelatin, while bone powder is used in the “powder method.” Using the chunk method, the gelatin yield (+5.29 ± 1.58%), %C (+0.62 ± 0.66%), and %N (+0.22 ± 0.22%) significantly increased, but the C/N ratio (−0.01 ± 0.03), δ13C (0.00 ± 0.09), and δ15N (−0.02 ± 0.21) did not significantly differ for 20 well-preserved bones. In 20 poorly preserved bones, the gelatin yield (+1.27 ± 1.33%), %N (+0.41 ± 0.49%), C/N ratio (−0.07 ± 0.07), and δ15N (−0.12 ± 0.37) significantly changed, but the %C (+0.37 ± 1.11%) and δ13C (−0.01 ± 0.09) were not significantly different using the chunk method. The observed significant differences have a sufficient statistical power (>0.8) with a significance level of 0.01 (except for the significant difference in δ15N of poorly preserved bones). The Fourier transform infrared spectra indicate that the extracted gelatin mostly consists of collagen without apparent contaminants. In general, in the context of palaeodietary studies, there are no actual differences in the δ13C and δ15N values obtained from the powder and chunk methods for gelatin from well preserved as well as poorly preserved bones.

Characteristics and Gelling Property of Gelatin from Scale of Spotted Golden Goatfish (Parupeneus heptacanthus )

Gelatins from the scales of spotted golden goatfish were extracted under different conditions and characterized. The gelatin yield, when extracted at 45, 60 and 75C (for 6 or 12 h), was 2.3–2.6%, 8.6–9.3% and 9.9–10.1% on dry weight basis, respectively. All the gelatins had β- and α-chains as the dominant components, and had high imino acid contents (182–192 residues/1,000 residues). Gel strength of the gelatin decreased and the gelatin solution became more turbid with increasing temperature and time of extraction. The gelling and melting temperatures of gelatin were 18.7–20.1 and 26.4–28.0C, respectively, and these decreased with extraction temperature and time. The results suggest that the scales of spotted golden goatfish have potential to serve as the collagenous raw material for gelatin extraction. Practical Applications Spotted golden goatfish (Parupeneus heptacanthus) is used in the manufacturing of frozen fish fillets in Thailand, and the scales with low market value are generated as byproducts. Large amounts of scales could potentially serve as raw material for gelatin production. However, the proper extraction conditions need to be determined experimentally, considering both yield and properties of the resulting gelatin.

Uskumru (Scomber scombrus) ve Levrek (Dicentrarchus labrax ) Kemiklerinden Jelatin Ekstraksiyonu ve Karakterizasyonu

The aims of this study were to determine the physicochemical properties of extracted gelatins from mackerel (Scomber scombrus) and sea bass (Dicentrarchus labrax) bones and compare with those of commercial fish and bovine gelatins. The yield of gelatin obtained from the bone of mackerel and sea bass were 5.98 and 6.20%, respectively. Two extracted gelatins showed higher protein content, lower moisture content compared to both commercial gelatins, indicates that the gelatin has considerably high purity. Melting temperatures of mackerel and sea bass bone gelatins were 25.5 and 23°C, respectively. Mackerel bone gelatin was yellow in appearance and higher L* value than both commercial gelatins. It can be concluded from the present study that mackerel and sea bass bone are a prospective source to produce gelatin in good yield with desirable functional properties comparable to commercially available mammalian and fish gelatins.

Characteristics and Gel Properties of Gelatin from Goat Skin as Affected by Extraction Conditions

Characteristics and gel properties of gelatin from goat skin, as influenced by extraction conditions, were studied. Yield of gelatin was 22.1–23.1% (wet weight basis). All gelatins contained α-chains as the predominant components, followed by β-chain. However, no β-chain was retained when extracted at 70C. Gelatin extracted at 50C for 2.5 h exhibited the highest gel strength (267 g) (P < 0.05). Gelling and melting temperatures for goat skin gelatin were in the ranges of 21.18–25.17C and 30.69–34.12C, respectively. Gel strength, gelling and melting temperatures of gelatin gels generally decreased with increasing extraction temperatures and times. Gels of gelatin extracted at a higher temperature for longer time had larger strands and voids. Gelatin extracted at 50C for 2.5 h contained imino acids of 225 residues/1,000 residues and showed higher gel strength than bovine gelatin. Thus, it could be used as a potential replacer for commercial gelatins. Practical Appications Gelatin has been used in food and non-food industries all over the world. With increasing demand of gelatin, particularly as the halal ingredient, the promising alternative raw material has been searched. Goat skin has become the potential collagenous starting material; however, the extraction conditions must be optimized to obtain the good quality gelatin. Therefore, gelatin from goat skin with properties equivalent to commercially available bovine or porcine counterparts can be produced and the goat skin can be better exploited.

Characterization and Film-Forming Properties of Gelatins from Whitemouth Croaker (Micropogonias furnieri) Skin and Bones

ABSTRACTThe Whitemouth croaker (Micropogonias furnieri), due to its abundance, is considered one of the most traditional and important species fished in the coastal waters and estuaries of South America. The aim of this work was to produce biopolymeric films of gelatins obtained from skin and bones of Whitemouth croaker. The fish gelatins were characterized through the yield, chemical composition, physiochemical, and rheological properties. The films were characterized by tensile strength (TS), elongation at break (EAB), water vapor permeability (WVP), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and optical properties. The values of protein yield, hydroxyproline content, gel strength, melting temperature, gelling temperature, and viscosity of the skin gelatin were higher than the values of the bone gelatin. The films obtained of skin gelatin showed all properties and thermal analysis superior in relation to the films of bone gelatin; this can be justified by the best physicochemical and rheological characteristics of the skin gelatin.

Pengaruh Variasi Konsentrasi Asam Asetat Terhadap Kuantitas Gelatin dari Kulit Ikan Sepat Rawa (Trichogaster trichopterus) Kering dan Karakterisasinya

This research was done to investigate the influence of concentration variations of acetic acid solution to the yield of gelatin produced from dry skins of sepat rawa fish (Trichogaster trichopterus) and their characteristics. Characterization done in this research include: organoleptis, strength, viscosity, acid degree (pH), level of water, ashes concentration, protein concentration and fat content of the gelatin. Data obtained was analyzed by using one way Duncan test using software statistic SPSS completed rose 17.0. Acetic acid concentrations used in this research were 1% v/v, 2% v/v, 6% v/v and 10% v/v. Acetic acid 6% v/v was the optimum concentration which yielded by gelatin in highest amount (5.8279%).

Alterations in juvenile diploid and triploid African catfish skin gelatin yield and amino acid composition: Effects of chlorpyrifos and butachlor exposures

Skin is a major by-product of the fisheries and aquaculture industries and is a valuable source of gelatin. This study examined the effect of triploidization on gelatin yield and proximate composition of the skin of African catfish (Clarias gariepinus). We further investigated the effects of two commonly used pesticides, chlorpyrifos (CPF) and butachlor (BUC), on the skin gelatin yield and amino acid composition in juvenile full-sibling diploid and triploid African catfish. In two separate experiments, diploid and triploid C. gariepinus were exposed for 21 days to graded CPF [mean measured: 10, 16, or 31 μg/L] or BUC concentrations [Mean measured: 22, 44, or 60 μg/L]. No differences in skin gelatin yield, amino acid or proximate compositions were observed between diploid and triploid control groups. None of the pesticide treatments affected the measured parameters in diploid fish. In triploids, however, gelatin yield was affected by CPF treatments while amino acid composition remained unchanged. Butachlor treatments did not alter any of the measured variables in triploid fish. To our knowledge, this study is the first to investigate changes in the skin gelatin yield and amino acid composition in any animal as a response to polyploidization and/or contaminant exposure.

Effects of acid concentration and the UHP pretreatment on the gelatinisation of collagen and the properties of extracted gelatins

SummaryAn ultra‐high‐pressure (UHP) transmission medium with HCl was applied as a pretreatment to extract gelatin. The effects of the acid concentration (0–1% (w/v)) on the gelatinisation of collagen and the properties of gelatin were investigated. An increase in the acid concentration decreased the thermostability of collagen and increased the yield of gelatin (from 64% increased to 80%). The content of the subunit components in the pretreated collagen and the gelatin declined slightly as the acid concentration was increased, resulted in slight decrease (P &gt; 0.05) in the gel strength (from 435 g decreased to 408 g). The analysis of Fourier transform infrared spectroscopy (FTIR) spectra showed that the triple‐helical structure, secondary structures of the collagen and covalent cross‐linking in the collagenous fibres were damaged gradually as the acid concentration was increased. The scanning electron microscopy (SEM) images showed that the smooth surface of collagen was partly disrupted with microvoids after UHP/1% HCl pretreatment, which may be related to the damage on the covalent cross‐linking.

Extraction and Characterization of Halal Gelatin from Fish Skin

Gelatin was extracted from fish skin of (mosa, EMG) flathead grey mullet, (hamor, EHG) greasy grouper and (bolti, EBG) Nile tilapia by a series of pretreatment with sodium hydroxide and citric acid. The results showed significant higher (p<0.05) gelatin yield from hamor skin (12.7 %) compared to other type of fish skins. The viscosity of hamor gelatin gel (7.73 cP) and bloom value (123.7g) were significantly higher (p<0.05) than gelatin gels from mosa and bolti. On the other hand, Gelatin extracted from mosa and bolti had similar gelatin yield, viscosity, gel strength and pH value. All extracted fish gelatin gels showed significant (p<0.05) higher viscosity value than halal bovine gelatin gel (HBG). The extracted gelatin has the potential use as halal gelatin to replace non-halal gelatin from porcine and nonhalal bovine.

Physicochemical Properties of Gelatin Extracted from Fivelined Threadfin Bream (Nemipterus tambuloides) Skins

&lt;p&gt;Gelatin has been extracted from fivelined threadfin bream fish using 0.05 M acetic acid. Extraction process was carried out at varying temperature of 60, 80 and 95oC for 3 h. Result indicated that extraction at 80oC showed the highest gel strength (187 Bloom) with viscosity of 12 cP. In fact, it produced the lowest yield (30.45%) with melting point of 31.67oC. Higher gelatin yield was shown by extraction at 95oC (38%) and the higher melting point was shown by extraction at 60oC and 95oC (around 34oC). Amino acids composition of the selected gelatin was similar to that of bovine gelatin. At concentration of 1-3% (w/v), emulsion stability index (ESI) of fish gelatin was lower than bovine gelatin. Emulsion activity index (EAI) was dependent on the gelatin concentration, at level of 1% and 2%, EAI of fish gelatin was considerably higher than bovine gelatin. At gelatin 3%, EAI of fish gelatin and bovine gelatin was similar. It suggests that the gelatin from fivelined threadfin bream skin has comparable physicochemical properties against bovine gelatin.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords&lt;/strong&gt;: Fivelined threadfin bream, gelatin, physicochemical properties. &lt;/p&gt;