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Hideki Kishimura - One of the best experts on this subject based on the ideXlab platform.
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characteristics of Gelatin extracted from the swim bladder of yellowfin tuna thunnus albacores as affected by alkaline pretreatments
Journal of Aquatic Food Product Technology, 2016Co-Authors: Onouma Kaewdang, Soottawat Benjakul, Thummanoon Prodpran, Thammarat Kaewmanee, Hideki KishimuraAbstract:ABSTRACTGelatins extracted from the swim bladder of yellowfin tuna (Thunnus albacores) using various alkaline pretreatments were characterized. Alkaline mixtures (Na2CO3:NaOH) at different ratios (9:1, 8:2, 7:3, and 6:4) with a concentration of 4% (w/v) were used. The corresponding Gelatins termed “G1,” “G2,” “G3,” and “G4” had yields of 9.78, 14.91, 35.96, and 13.60% (dry weight basis), respectively. All Gelatins had α-chains as the major components. Fourier transform infrared spectra of obtained Gelatins revealed the significant loss of molecular order of the triple-helix. G3 having the highest imino acid content and exhibited the highest gel strength (p < 0.05), compared with others. The microstructure of G3 gel was finer with smaller voids, compared with others. With increasing proportion of NaOH, the L*-value of Gelatin gel increased with coincidental decrease in ΔE*-value. Gelling and melting temperatures of swim bladder Gelatin were 12.3–15.1 and 21.3–22.3°C, respectively.
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characteristics of Gelatin from swim bladder of yellowfin tuna thunnus albacores as influenced by extracting temperatures
Italian Journal of Food Science, 2015Co-Authors: Onouma Kaewdang, Soottawat Benjakul, Thummanoon Prodpran, Thammarat Kaewmanee, Hideki KishimuraAbstract:Gelatin was extracted from the swim bladder of yellowfin tuna (Thunnus albacores) at different temperatures (60, 70 and 80°C) with the extraction yields of 35.6%, 41.1% and 47.3% (dry weight basis), respectively. The α-chains of Gelatin decreased with increasing extraction temperatures. Similar amino acid compositions were noticeable among all Gelatins, in which glycine constituted the major amino acid. Imino acids ranged from 169 to 172 residues/1,000 residues. The gel strength of Gelatin extracted at lower temperature was higher than that of Gelatins extracted at higher temperatures. Gelling and melting temperatures for swim bladder Gelatin were 11.07- 15.24 and 20.36-22.33°C, respectively. Higher gelling and melting points were observed for Gelatin extracted at lower temperatures. Microstructure of gel of Gelatin extracted at 60°C was finer with smaller voids, compared with others. FTIR spectra of obtained Gelatins revealed the significant loss of molecular order of the triple-helix. Thus, extraction temperatures showed the direct impact on characteristics of Gelatin from swim bladder.
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characteristics and functional properties of Gelatin from splendid squid loligo formosana skin as affected by extraction temperatures
Food Hydrocolloids, 2012Co-Authors: Muralidharan Nagarajan, Soottawat Benjakul, Thummanoon Prodpran, Ponusa Songtipya, Hideki KishimuraAbstract:Gelatin was extracted from the skin of splendid squid (Loligo formosana) at different temperatures (50, 60, 70 and 80 °C) with extraction yield of 8.8%, 21.8%, 28.2%, and 45.3% (dry weight basis) for G50, G60, G70 and G80, respectively. Gelatin from the skin of splendid squid had a high protein content (∼90%) with low moisture (8.63–11.09%), fat (0.22–0.31%) and ash contents (0.17–0.68%). Gelatin extracted at higher temperature (G80) had a relatively higher free amino group content than Gelatin extracted at lower temperatures (G50, G60 and G70) (P < 0.05). All Gelatins contained α- and β-chains as the predominant components. Amino acid analysis of Gelatin revealed the high proline and hydroxyproline contents for G50 and G60. FTIR spectra of obtained Gelatins revealed the significant loss of molecular order of the triple-helix. The gel strength of Gelatin extracted at lower temperature (G50) was higher than that of Gelatins extracted at higher temperatures including G60, G70 and G80, respectively. The net charge of G50, G60, G70 and G80 became zero at pHs of 6.84, 5.94, 5.49, and 4.86, respectively, as determined by zeta potential titration. Gelatin extracted at higher temperature (G80) had the lower L* value but higher a* and b* values, compared with those extracted at lower temperatures (P < 0.05). Emulsion activity index decreased, whilst emulsion stability index, foam expansion and stability increased as the concentration (1–3%) increased (P < 0.05). Those properties were governed by extraction temperatures of Gelatin. Thus Gelatin can be successfully extracted from splendid squid skin using the appropriate extraction temperature.
Soottawat Benjakul - One of the best experts on this subject based on the ideXlab platform.
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characteristics of Gelatin extracted from the swim bladder of yellowfin tuna thunnus albacores as affected by alkaline pretreatments
Journal of Aquatic Food Product Technology, 2016Co-Authors: Onouma Kaewdang, Soottawat Benjakul, Thummanoon Prodpran, Thammarat Kaewmanee, Hideki KishimuraAbstract:ABSTRACTGelatins extracted from the swim bladder of yellowfin tuna (Thunnus albacores) using various alkaline pretreatments were characterized. Alkaline mixtures (Na2CO3:NaOH) at different ratios (9:1, 8:2, 7:3, and 6:4) with a concentration of 4% (w/v) were used. The corresponding Gelatins termed “G1,” “G2,” “G3,” and “G4” had yields of 9.78, 14.91, 35.96, and 13.60% (dry weight basis), respectively. All Gelatins had α-chains as the major components. Fourier transform infrared spectra of obtained Gelatins revealed the significant loss of molecular order of the triple-helix. G3 having the highest imino acid content and exhibited the highest gel strength (p < 0.05), compared with others. The microstructure of G3 gel was finer with smaller voids, compared with others. With increasing proportion of NaOH, the L*-value of Gelatin gel increased with coincidental decrease in ΔE*-value. Gelling and melting temperatures of swim bladder Gelatin were 12.3–15.1 and 21.3–22.3°C, respectively.
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characteristics of Gelatin from swim bladder of yellowfin tuna thunnus albacores as influenced by extracting temperatures
Italian Journal of Food Science, 2015Co-Authors: Onouma Kaewdang, Soottawat Benjakul, Thummanoon Prodpran, Thammarat Kaewmanee, Hideki KishimuraAbstract:Gelatin was extracted from the swim bladder of yellowfin tuna (Thunnus albacores) at different temperatures (60, 70 and 80°C) with the extraction yields of 35.6%, 41.1% and 47.3% (dry weight basis), respectively. The α-chains of Gelatin decreased with increasing extraction temperatures. Similar amino acid compositions were noticeable among all Gelatins, in which glycine constituted the major amino acid. Imino acids ranged from 169 to 172 residues/1,000 residues. The gel strength of Gelatin extracted at lower temperature was higher than that of Gelatins extracted at higher temperatures. Gelling and melting temperatures for swim bladder Gelatin were 11.07- 15.24 and 20.36-22.33°C, respectively. Higher gelling and melting points were observed for Gelatin extracted at lower temperatures. Microstructure of gel of Gelatin extracted at 60°C was finer with smaller voids, compared with others. FTIR spectra of obtained Gelatins revealed the significant loss of molecular order of the triple-helix. Thus, extraction temperatures showed the direct impact on characteristics of Gelatin from swim bladder.
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characteristics and functional properties of Gelatin from splendid squid loligo formosana skin as affected by extraction temperatures
Food Hydrocolloids, 2012Co-Authors: Muralidharan Nagarajan, Soottawat Benjakul, Thummanoon Prodpran, Ponusa Songtipya, Hideki KishimuraAbstract:Gelatin was extracted from the skin of splendid squid (Loligo formosana) at different temperatures (50, 60, 70 and 80 °C) with extraction yield of 8.8%, 21.8%, 28.2%, and 45.3% (dry weight basis) for G50, G60, G70 and G80, respectively. Gelatin from the skin of splendid squid had a high protein content (∼90%) with low moisture (8.63–11.09%), fat (0.22–0.31%) and ash contents (0.17–0.68%). Gelatin extracted at higher temperature (G80) had a relatively higher free amino group content than Gelatin extracted at lower temperatures (G50, G60 and G70) (P < 0.05). All Gelatins contained α- and β-chains as the predominant components. Amino acid analysis of Gelatin revealed the high proline and hydroxyproline contents for G50 and G60. FTIR spectra of obtained Gelatins revealed the significant loss of molecular order of the triple-helix. The gel strength of Gelatin extracted at lower temperature (G50) was higher than that of Gelatins extracted at higher temperatures including G60, G70 and G80, respectively. The net charge of G50, G60, G70 and G80 became zero at pHs of 6.84, 5.94, 5.49, and 4.86, respectively, as determined by zeta potential titration. Gelatin extracted at higher temperature (G80) had the lower L* value but higher a* and b* values, compared with those extracted at lower temperatures (P < 0.05). Emulsion activity index decreased, whilst emulsion stability index, foam expansion and stability increased as the concentration (1–3%) increased (P < 0.05). Those properties were governed by extraction temperatures of Gelatin. Thus Gelatin can be successfully extracted from splendid squid skin using the appropriate extraction temperature.
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characteristics of Gelatin from the skin of unicorn leatherjacket aluterus monoceros as influenced by acid pretreatment and extraction time
Food Hydrocolloids, 2011Co-Authors: Mehraj Ahmad, Soottawat BenjakulAbstract:Abstract Gelatins from the skin of unicorn leatherjacket ( Aluterus monoceros ) pretreated with different acids (0.2 M acetic acid or 0.2 M phosphoric acid) and extracted with distilled water at 45 °C for various times (4 and 8 h) were characterized. Yields of 5.23–9.18 or 6.12–11.54% (wet weight basis) were obtained for Gelatins extracted from the skin pretreated with 0.2 M acetic acid or 0.2 M phosphoric acid, respectively. Extracted Gelatins contained α 1 and α 2 chains as the predominant components and some degradation peptides. The absorption bands of Gelatins in FTIR spectra were mainly situated in the amide band region (amide I, amide II and amide ІІІ) and showed the significant loss of molecular order of triple helix. Gelatin samples had a relative solubility greater than 90% in the wide pH ranges (1–10). The gel strength of Gelatin from skin pretreated with phosphoric acid (GPA) was higher than that of Gelatin from skin pretreated with acetic acid (GAA). Both GPA and GAA had the lower gel strength than that of commercial bovine Gelatin ( P
Yeunsuk Gu - One of the best experts on this subject based on the ideXlab platform.
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extracting optimization and physical properties of yellowfin tuna thunnus albacares skin Gelatin compared to mammalian Gelatins
Food Hydrocolloids, 2005Co-Authors: Yeunsuk GuAbstract:Abstract This work is to optimize Gelatin extraction from dorsal skin of yellowfin tuna (Thunnus albacares) using response surface methodology, and to compare physical properties of yellowfin tuna skin Gelatin with those of two mammalian skin Gelatins (bovine and porcine). Central composite design was adopted in Gelatin processing for extracting optimization. Concentration of NaOH (X1), treatment time (X2), extraction temperature (X3) and extraction time (X4) were chosen for independent variables. Dependent variables were gel strength (Y1) and Gelatin content (Y2). Optimal conditions were X1=1.89(%), X2=2.87 (days), X 3 =58.15 (° C ) and X4=4.72 (h), and predicted values of multiple response optimal conditions were Y1=429.1 (Bloom) and Y2=89.7 (%). In order to investigate physical properties of yellowfin tuna skin Gelatin, gel strength, gelling and melting points, and dynamic viscoelastic properties were measured. The gel strength of yellowfin tuna skin Gelatin (426 Bloom) was higher than bovine and porcine Gelatins (216 Bloom and 295 Bloom, respectively), while gelling and melting points were lower. Dynamic viscoelastic properties of yellowfin tuna skin Gelatin did not change at 20 °C, but increase at 10 °C as a similar pattern with mammalian Gelatins.
M C Gomezguillen - One of the best experts on this subject based on the ideXlab platform.
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antioxidant and functional properties of Gelatin hydrolysates obtained from skin of sole and squid
Food Chemistry, 2009Co-Authors: B Gimenez, P Montero, A Aleman, M C GomezguillenAbstract:Abstract Antioxidant and functional properties were evaluated for Gelatin hydrolysates obtained from sole and squid skin Gelatin by Alcalase, with a degree of hydrolysis of ∼35% and ∼50%, respectively. Both hydrolysates mainly consisted of peptides below 6.5 kDa, together with peptidic material from around 16 to 6.5 kDa. Moreover, the squid hydrolysate showed a peptide band of around 26 kDa. Antioxidant properties of both Gelatins were highly increased by hydrolysis, especially ABTS and metal chelating abilities. The squid hydrolysate showed the highest antioxidant capacity by FRAP, ABTS and metal chelating assays in spite of the lower content in hydrophobic amino acids. Both Gelatin hydrolysates had a good solubility (over 95%). The emulsifying activity index (EAI) decreased with increasing concentration. Conversely, the foam expansion increased with increasing concentration. However, both foam and emulsion stabilities were not apparently affected by the concentration of hydrolysate. In the case of the sole hydrolysate, which showed a lower degree Pro and Lys hydroxylation, foam stability was very poor, and 50% of foam expansion was lost after 5 min at all concentrations.
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fish Gelatin a renewable material for developing active biodegradable films
Trends in Food Science and Technology, 2009Co-Authors: M C Gomezguillen, B Gimenez, Miriam Perezmateos, Joaquin Gomezestaca, E Lopezcaballero, P MonteroAbstract:Most films used to preserve foodstuffs are made from synthetic plastic materials. However, for environmental reasons, attention has recently turned to biodegradable films. Gelatin has been extensively studied for its film-forming capacity and applicability as an outer covering to protect food against drying, light, and oxygen. Moreover, it is one of the first materials proposed as a carrier of bioactive components. Gelatins from alternatives to mammalian species are gaining prominence, especially Gelatins from marine fish species. Because of their good film-forming abilities, fish Gelatins may be a good alternative to synthetic plastics for making films to preserve foodstuffs. The mechanical and barrier properties of these films depend largely on the physical and chemical characteristics of the Gelatin, especially the amino acid composition, which is highly species specific, and the molecular weight distribution, which depends mainly on processing conditions. Different film formulations can be developed to extend the films' physical and chemical properties and to add new functional attributes. This paper reviews the most recent scientific literature dealing with films based on Gelatins from different fish species and considers various strategies intended to improve the physical properties of such films by combining fish Gelatins with such other biopolymers as soy protein isolate, oils and fatty acids, and certain polysaccharides. The use of plasticizers and cross-linking agents is also discussed. Specific attributes, such as antimicrobial and antioxidant activities, may be also conferred by blending the Gelatin with chitosan, lysozyme, essential oils, plant extracts, or vitamin C to produce an active packaging biomaterial.
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use of lactic acid for extraction of fish skin Gelatin
Food Hydrocolloids, 2005Co-Authors: B Gimenez, Javier Turnay, M A Lizarbe, P Montero, M C GomezguillenAbstract:The ability of lactic acid compared to acetic acid for Dover sole (Solea vulgaris) skin swelling and the subsequent Gelatin extraction was examined. The resultant Gelatins were evaluated in terms of extraction yield, amino acid composition, molecular weight distribution, gel strength, viscoelastic properties, ability to refold into triple helical structures, and aggregation phenomena. Lactic acid (25 mM) proved to be an excellent substitute for acetic acid during the skin swelling process, as the Gelatin preparation thus obtained presented quite similar properties to that prepared by using 50 mM acetic acid without the negative organoleptic properties of this acid. However, the application of 50 mM lactic acid gave rise to a highly hydrolysed Gelatin, with lower folding ability, gel strength and viscoelastic properties than those obtained using 25 mM lactic acid or 50 mM acetic acid.
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structural and physical properties of Gelatin extracted from different marine species a comparative study
Food Hydrocolloids, 2002Co-Authors: M C Gomezguillen, Javier Turnay, M A Lizarbe, M D Fernandezdiaz, N Ulmo, P MonteroAbstract:Gelatin from skins of several marine species were compared on the basis of their rheological characteristics (viscoelasticity and gel strength) and chemical/structural properties (amino acid composition, molecular weight distribution and triple helix formation). Gelatins from flat-fish species (sole and megrim) presented the best gelling ability and the gels were more thermostable than those from cold-adapted fish (cod and hake). This different behaviour may be explained considering the amino acid composition, the α1/α2 collagen-chain ratio, and the molecular weight distribution. Thus, cod Gelatin presented a lower alanine and imino acid content, and a decreased proline hydroxylation degree; cod and hake Gelatins presented a low α1/α2 ratio (∼1); hake Gelatin showed a highly significant decrease in β-components and other aggregates. The squid Gelatin presented the most significant changes regarding amino acid composition and molecular weight distribution, most of these differences arising from the low solubility of the squid connective tissue. However, the squid Gelatin showed viscoelastic properties intermediate between those from flat-fish and cold-adapted fish species. Circular dichroism analysis reveals that gelling involves a refolding of denatured collagen chains into the typical triple helix conformation and, conversely, unfolding upon reheating. Thermal folding and unfolding curves were similar to those of viscoelastic properties but showing a shift towards lower or higher temperatures upon cooling and heating, respectively. The folding process seem to be directly related in the stabilisation of the gels without disregarding its role in triggering the gelation process. Finally, gel strength evaluation revealed the importance of slow cold maturation.
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gel properties of collagens from skins of cod gadus morhua and hake merluccius merluccius and their modification by the coenhancers magnesium sulphate glycerol and transglutaminase
Food Chemistry, 2001Co-Authors: M D Fernandezdiaz, P Montero, M C GomezguillenAbstract:Abstract The gel properties of two different kinds of fish Gelatins prepared from cod ( Gadus morhua ) and hake ( Merluccius merluccius ) and modified by the coenhancers glycerol, salt and microbial transglutaminase, were examined. Gel strength was substantially increased by the addition of coenhancers although results varied, depending on the species. In Gelatin from hake ( M. merluccius ) skin, the highest values were obtained with 10 mg/g of transglutaminase, whereas magnesium sulphate was more effective at both concentrations (0.1 and 0.5 M) in Gelatin from cod ( G. morhua ) skin. Although, in both Gelatins, the addition of any ingredient increased the viscosity modulus (G″), the elastic modulus (G′) was only increased by the addition of glycerol 15% (w/v) and MgSO 4 0.5 M in hake ( M. merluccius ) Gelatins; in cod ( G. morhua ) it was increased by all ingredients. The gelling and melting points, very important properties in fish Gelatin, showed a notable improvement, the behaviour being different, depending on the species.
P Montero - One of the best experts on this subject based on the ideXlab platform.
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antioxidant and functional properties of Gelatin hydrolysates obtained from skin of sole and squid
Food Chemistry, 2009Co-Authors: B Gimenez, P Montero, A Aleman, M C GomezguillenAbstract:Abstract Antioxidant and functional properties were evaluated for Gelatin hydrolysates obtained from sole and squid skin Gelatin by Alcalase, with a degree of hydrolysis of ∼35% and ∼50%, respectively. Both hydrolysates mainly consisted of peptides below 6.5 kDa, together with peptidic material from around 16 to 6.5 kDa. Moreover, the squid hydrolysate showed a peptide band of around 26 kDa. Antioxidant properties of both Gelatins were highly increased by hydrolysis, especially ABTS and metal chelating abilities. The squid hydrolysate showed the highest antioxidant capacity by FRAP, ABTS and metal chelating assays in spite of the lower content in hydrophobic amino acids. Both Gelatin hydrolysates had a good solubility (over 95%). The emulsifying activity index (EAI) decreased with increasing concentration. Conversely, the foam expansion increased with increasing concentration. However, both foam and emulsion stabilities were not apparently affected by the concentration of hydrolysate. In the case of the sole hydrolysate, which showed a lower degree Pro and Lys hydroxylation, foam stability was very poor, and 50% of foam expansion was lost after 5 min at all concentrations.
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fish Gelatin a renewable material for developing active biodegradable films
Trends in Food Science and Technology, 2009Co-Authors: M C Gomezguillen, B Gimenez, Miriam Perezmateos, Joaquin Gomezestaca, E Lopezcaballero, P MonteroAbstract:Most films used to preserve foodstuffs are made from synthetic plastic materials. However, for environmental reasons, attention has recently turned to biodegradable films. Gelatin has been extensively studied for its film-forming capacity and applicability as an outer covering to protect food against drying, light, and oxygen. Moreover, it is one of the first materials proposed as a carrier of bioactive components. Gelatins from alternatives to mammalian species are gaining prominence, especially Gelatins from marine fish species. Because of their good film-forming abilities, fish Gelatins may be a good alternative to synthetic plastics for making films to preserve foodstuffs. The mechanical and barrier properties of these films depend largely on the physical and chemical characteristics of the Gelatin, especially the amino acid composition, which is highly species specific, and the molecular weight distribution, which depends mainly on processing conditions. Different film formulations can be developed to extend the films' physical and chemical properties and to add new functional attributes. This paper reviews the most recent scientific literature dealing with films based on Gelatins from different fish species and considers various strategies intended to improve the physical properties of such films by combining fish Gelatins with such other biopolymers as soy protein isolate, oils and fatty acids, and certain polysaccharides. The use of plasticizers and cross-linking agents is also discussed. Specific attributes, such as antimicrobial and antioxidant activities, may be also conferred by blending the Gelatin with chitosan, lysozyme, essential oils, plant extracts, or vitamin C to produce an active packaging biomaterial.
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use of lactic acid for extraction of fish skin Gelatin
Food Hydrocolloids, 2005Co-Authors: B Gimenez, Javier Turnay, M A Lizarbe, P Montero, M C GomezguillenAbstract:The ability of lactic acid compared to acetic acid for Dover sole (Solea vulgaris) skin swelling and the subsequent Gelatin extraction was examined. The resultant Gelatins were evaluated in terms of extraction yield, amino acid composition, molecular weight distribution, gel strength, viscoelastic properties, ability to refold into triple helical structures, and aggregation phenomena. Lactic acid (25 mM) proved to be an excellent substitute for acetic acid during the skin swelling process, as the Gelatin preparation thus obtained presented quite similar properties to that prepared by using 50 mM acetic acid without the negative organoleptic properties of this acid. However, the application of 50 mM lactic acid gave rise to a highly hydrolysed Gelatin, with lower folding ability, gel strength and viscoelastic properties than those obtained using 25 mM lactic acid or 50 mM acetic acid.
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structural and physical properties of Gelatin extracted from different marine species a comparative study
Food Hydrocolloids, 2002Co-Authors: M C Gomezguillen, Javier Turnay, M A Lizarbe, M D Fernandezdiaz, N Ulmo, P MonteroAbstract:Gelatin from skins of several marine species were compared on the basis of their rheological characteristics (viscoelasticity and gel strength) and chemical/structural properties (amino acid composition, molecular weight distribution and triple helix formation). Gelatins from flat-fish species (sole and megrim) presented the best gelling ability and the gels were more thermostable than those from cold-adapted fish (cod and hake). This different behaviour may be explained considering the amino acid composition, the α1/α2 collagen-chain ratio, and the molecular weight distribution. Thus, cod Gelatin presented a lower alanine and imino acid content, and a decreased proline hydroxylation degree; cod and hake Gelatins presented a low α1/α2 ratio (∼1); hake Gelatin showed a highly significant decrease in β-components and other aggregates. The squid Gelatin presented the most significant changes regarding amino acid composition and molecular weight distribution, most of these differences arising from the low solubility of the squid connective tissue. However, the squid Gelatin showed viscoelastic properties intermediate between those from flat-fish and cold-adapted fish species. Circular dichroism analysis reveals that gelling involves a refolding of denatured collagen chains into the typical triple helix conformation and, conversely, unfolding upon reheating. Thermal folding and unfolding curves were similar to those of viscoelastic properties but showing a shift towards lower or higher temperatures upon cooling and heating, respectively. The folding process seem to be directly related in the stabilisation of the gels without disregarding its role in triggering the gelation process. Finally, gel strength evaluation revealed the importance of slow cold maturation.
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gel properties of collagens from skins of cod gadus morhua and hake merluccius merluccius and their modification by the coenhancers magnesium sulphate glycerol and transglutaminase
Food Chemistry, 2001Co-Authors: M D Fernandezdiaz, P Montero, M C GomezguillenAbstract:Abstract The gel properties of two different kinds of fish Gelatins prepared from cod ( Gadus morhua ) and hake ( Merluccius merluccius ) and modified by the coenhancers glycerol, salt and microbial transglutaminase, were examined. Gel strength was substantially increased by the addition of coenhancers although results varied, depending on the species. In Gelatin from hake ( M. merluccius ) skin, the highest values were obtained with 10 mg/g of transglutaminase, whereas magnesium sulphate was more effective at both concentrations (0.1 and 0.5 M) in Gelatin from cod ( G. morhua ) skin. Although, in both Gelatins, the addition of any ingredient increased the viscosity modulus (G″), the elastic modulus (G′) was only increased by the addition of glycerol 15% (w/v) and MgSO 4 0.5 M in hake ( M. merluccius ) Gelatins; in cod ( G. morhua ) it was increased by all ingredients. The gelling and melting points, very important properties in fish Gelatin, showed a notable improvement, the behaviour being different, depending on the species.
