Fish Myofibrillar Protein Research Articles

Effect of Ionic Strength and Temperature on Interaction between Fish Myoglobin and Myofibrillar Proteins

The effects of ionic strength (0, 0.3, and 0.6 M KCl) and temperature (4 and 25 degrees C) on the interaction between fish myoglobin and myofibrillar proteins were investigated in a model system. Increases in the relative content of bound myoglobin and metmyoglobin formation in myoglobin-natural actomyosin (NAM) mixtures with concurrent decreases in whiteness and Ca(2+)-ATPase activity were observed with increasing ionic strength (P < 0.05). The relative content of bound myoglobin and the oxidation of oxymyoglobin were generally greater at 25 degrees C than at 4 degrees C (P < 0.05). Binding of myoglobin to NAM resulted in decreased whiteness (P < 0.05). Ca(2+)-ATPase was not affected by temperature (P > 0.05). SDS-PAGE patterns of protein samples suggested that myoglobin-NAM interactions did not involve disulfide bonds. The formation of high-molecular-weight aggregates (>206 kDa) was observed and was more pronounced at higher ionic strength and higher temperature.

Cysteine proteinase inhibitor from chicken plasma: Fractionation, characterization and autolysis inhibition of fish myofibrillar proteins

Cysteine proteinase inhibitor (CPI) from chicken plasma was fractionated by using polyethylene glycol (PEG-4000) or ammonium sulfate (AS). Addition of PEG, at the level of 200–400 g/l based on the original volume of plasma protein, was more effective to fractionate CPI than was using AS. Highest inhibitory activity and purification-fold were obtained in the PEG precipitate II (CPI fraction). The CPI fraction was stable in the temperature ranges of 40–90 °C for 10 min but extended incubation time at 90 °C markedly decreased the inhibitory activity of the CPI fraction. The fraction was stable in the broad pH ranges tested (3–10). NaCl concentrations of 0.5–3% did not affect the inhibitory activity of the CPI fraction. The CPI fraction effectively prevented the degradation of mince and washed mince from Pacific whiting; however, lower efficacy in inhibiting autolysis of the arrowtooth flounder mince and the washed mince was observed, suggesting differences in initial proteolytic activity between the two species. Therefore, the CPI fraction from chicken plasma could be an alternative food grade inhibitor for the surimi industry.

Effect of Fluctuations of Temperature During Frozen Storage on Denaturation of Fish Myofibrillar Protein

Effect of Fluctuations of Temperature During Frozen Storage on Denaturation of Fish Myofibrillar Protein

Effect of Artificial Diets on Growth, Survival and Condition of Adult Cuttlefish, Sepia officinalis Linnaeus, 1758

The effects of artificial diets on growth and body condition of adult cuttlefish, Sepia officinalis were tested in two experiments. Supplemented prepared diets (fish myofibrillar protein concentrate) were fed during a 30-day and a 21-day experiments. Growth, feeding rate and food conversion of group-reared cuttlefish were analyzed. The first of these experiments tested four artificial diets, made with increasing levels of lysine, on adult cuttlefish. According to the chemical analysis, diets 1–3 had limiting concentrations of lysine and other essential amino acids (compared to mantle composition of the cuttlefish), while diet 4 was the only one where almost all essential amino acids were present in concentrations similar or higher than the ones present in cuttlefish mantle. A second experiment was conducted by isolating 16 adult cuttlefish individually, and feeding them the same four artificial diets, in order to obtain individual data. During Experiment 1, only the diet with the best chemical score (diet 4) produced growth (p < 0.05), with a mean instantaneous growth rate (MIGR) of 0.30% wet body weight (BW) d−1. Similarly, individually reared cuttlefish fed diet 4 produced the highest IGR’s (0.26, 0.38 and 0.48% BW d−1) and grew larger (p < 0.01). Comparison of cuttlefish fed the artificial diets vs. thawed shrimp and unfed cuttlefish indicated that cuttlefish fed the artificial diets were in an intermediate state. Growth rates obtained with the artificial diets (<0.4% BW d−1) were considerably lower compared to natural prey, live or frozen, reported by other authors.

Effect of trehalose on the gel-forming ability, state of water and myofibril denaturation of horse mackerel Trachurus japonicus surimi during frozen storage

The cryoprotective effects of trehalose on fish myofibrillar protein were compared with those of sucrose, glucose and sorbitol. The frozen surimi with trehalose exhibited significantly higher Ca2+-ATPase activity through-out the storage periods, resulting in higher gel-forming ability than that of without trehalose. The amount of unfrozen water was significantly increased in the surimi upon addition of trehalose at any concentrations tested. The findings suggest that trehalose constructed bound water molecules in protein structure, consequently suppressed freeze-induced denaturation of protein and maintained gel-forming ability. An addition of 5.0% to 7.5% concentration of trehalose showed threshold behavior to increase the amount of unfrozen water and to prevent freeze-induced denaturation of protein. The effects of trehalose were almost similar to those of other sugars.

Characterization of Fish Myofibrillar Protein by Conjugation with Alginate Oligosaccharide Prepared Using Genetic Recombinant Alginate Lyase

ABSTRACT: The production of alginate lyase using genetically modified Escherichia coli was superior to the purification of alginate lyase from a culture medium of Pseudoalteromonas elyakovii regarding production efficiency. When alginate oligosaccharide (AO) prepared using genetic recombinant alginate lyase was introduced to fish myofibrillar proteins, the protein obtained high water solubility and improved thermal stability, similarly to AO prepared using wild-type lyase. Therefore, the use of genetic recombinant technology for the production of alginate lyase would be useful for the functional improvement of fish myofibrillar proteins by conjugation with AO.

Effect of Shrimp Chitin and Shrimp Chitin Hydrolysate on the State of Water and Dehydration-induced Denaturation of Lizard Fish Myofibrillar Protein

To assess the potential utilization of shrimp waste, shrimp chitin (SC) and shrimp chitin hydrolysate (SCH) were prepared from black tiger (Penaeus monodon), endeavour (Metapenaeus endeavouri) and giant freshwater (Macrobrachium rosenbergii) prawns. Effect of SC and SCH on the state of water and denaturation of lizard fish (Saurida wanieso) myofibrillar protein (Mf) at concentrations of 5% (dry weight/wet weight) were assessed based on water activity (Aw) and changes in Mf Ca-ATPase activity during dehydration. The effect was compared with untreated Mf (control) and Mf containing glucose. The Aw of Mf for each SCH was remarkably lower than the Mf with SC and control. The Mf with SCH showed a remarkably high level of inactivated Ca-ATPase activity, followed by Mf with SC and the control. Mf with glucose showed slightly higher inactivated Ca-ATPase activity than SCH, reaching Aw levels of 0.65, before rapidly decreasing. These findings revealed that SCH contributed to the retardation effect on dehydration-induced denaturation of Mf by stabilizing hydrated water molecules surrounding the Mf.

Improved solubility and stability of carp myosin by conjugation with alginate oligosaccharide

: Carp myosin was conjugated with alginate oligosaccharide (AO) through the Maillard reaction under low relative humidity, and the functional properties of the myosin-AO conjugate were investigated to clarify the role of myosin in the functional improvement of fish myofibrillar proteins (Mf) by the glycosylation. The findings were as follows. First, myosin became highly solubilized at lower NaCl concentrations by conjugation with AO and NaCl-dependence of the solubility was lost when > 12% of the available lysine residues were reacted with AO and 50 µg/mg of AO was attached to myosin. Second, the thermal stability of myosin was effectively improved by conjugation with AO. Heat-treatment at 50°C for 6 h has no effect on the solubility of the myosin-AO conjugate regardless of the NaCl concentration. Third, the improved functionalities of myosin conjugated with AO remained even at a nearly isoelectric point. The improving effect of AO-conjugation on the characteristics of myosin was almost the same as Mf reacted with AO. Therefore, it is apparent that that improved functionalities of the glycosylated Mf reflect the functional changes of myosin.

Temperature, color, and texture prediction models for surimi seafood pasteurization.

Surimi is a frozen concentrate of fish myofibrillar proteins stabilized with cryoprotectants. It is a major ingredient, along with other compounds (flavors, starches, protein additives, etc.), for surimi seafood products such as crabmeat analog. Surimi seafood is a ready-to-eat product, which requires precise pasteurization practice for product quality and safety. Due to good sensory characteristics and relatively low price, compared to natural counterparts, surimi seafood has its own, well-established position in the market and is well recognized by consumers (Shie and Park, 1999).KeywordsCold SpotAlpha CorrectionMicrobial SafetySeafood SamplePasteurization SettingThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Effect of pH on the preparation of edible films based on fish myofibrillar proteins

ABSTRACT: Transparent and flexible edible/biodegradable films were successfully made from myofibrillar proteins of blue marlin meat. The effect of pH of film-forming solutions on film formation, tensile strength (TS), elongation at break (EAB), water vapor permeability (WVP), light transmission, transparency, film solubility, protein solubility and enzymatic hydrolysis was investigated. Myofibrillar protein-based films were formed within pH 2–3 and 7–12, whereas films were not formed between pH 4 and 6 because of the poor protein dispersion around the isoelectric point. TS of the films was higher when prepared at the acidic (pH 2, 3) and alkaline (pH 11, 12) conditions, whereas EAB was almost constant irrespective of pH. On the whole, the pH of film-forming solutions had no effect on WVP, light transmission, film solubility and enzymatic hydrolysis. WVP of myofibrillar protein films were slightly lower than those of other protein-based edible films and higher by one to three orders of magnitude than those of synthetic films. The films prepared at lower or higher pH, which had a more stable protein network, possessed superior transparency close to synthetic films.

Effect of proteolytic squid protein hydrolysate on the state of water and dehydration-induced denaturation of lizard fish myofibrillar protein.

With the goal of preparing low-cost functional food, squid protein hydrolysate (SPH) was extracted from four squid species by protease treatment. Peptides are the major components (approximately 84-88%) of the SPH. The stabilization effects of 5% SPH (dried weight/wet weight) on the state of water and the denaturation of frozen lizard fish Saurida wanieso myofibrillar protein (Mf) were evaluated on the basis of desorption isotherm curves with respect to Ca2+-ATPase inactivation and the presence of unfrozen water, which was determined using differential scanning calorimetry during dehydration, and the effects were compared with those of sodium glutamate. The Mf with SPH was found to contain higher levels of monolayer and multilayer sorption water, resulting in decreased water activity and Ca2+-ATPase inactivation. The amount of unfrozen water in Mf with SPH increased significantly, suggesting that the peptides of SPH stabilized water molecules on the hydration sphere of Mf, which maintained the structural stability of Mf, and therefore suppressed dehydration-induced denaturation. The effect by SPH was less than that by sodium glutamate.

Stability and emulsion-forming ability of water-soluble fish myofibrillar protein prepared by conjugation with alginate oligosaccharide.

Carp myofibrillar protein (Mf) was conjugated with alginate oligosaccharide (AO) through the Maillard reaction under low relative humidity, and the functional properties of the Mf-AO conjugate were investigated under different NaCl concentrations and pH levels. Mf became highly solubilized at lower NaCl concentrations by conjugation with AO, with a slight loss of available lysine. The thermal stability of Mf was effectively improved by conjugation with AO. Heat treatment at 80 degrees C for 2 h had no effect on the solubility of the Mf-AO conjugate attached to 227 microg/mg of AO regardless of the NaCl concentration and pH. Furthermore, the Mf-AO conjugate showed excellent emulsion-forming ability regardless of NaCl concentration. The improved functionalities of Mf by conjugation with AO remained even at a nearly isoelectric point. These results indicate that conjugation with AO through the Maillard reaction is an effective way to prepare high-functional food material from fish muscle protein.

Effect of chitin hydrolysate on the denaturation of lizard fish myofibrillar protein and the state of water during frozen storage

We investigated the effect of chitin hydrolysate made from crustacean shells and cephalopod cartilage on the denaturation and state of water in lizard fish myofibrillar protein (Mf) during frozen storage at −25 °C for 120 days. The chitin hydrolysate (2.5–12.5 g dry weight) was added to 100 g of the Mf, and the changes in the Mf Ca–ATPase activity and the amount of unfrozen water in the Mf were examined during frozen storage. The addition of chitin hydrolysate markedly decreased the inactivation rate of the Mf Ca–ATPase. The amount of unfrozen water in the Mf increased upon the addition of chitin hydrolysate, and then decreased gradually during frozen storage. On the other hand, the amount of unfrozen water in the control dropped drastically during the initial period of frozen storage. At a concentration of over 5.0%, chitin hydrolysates completely suppressed the inactivation of the Ca–ATPase and maximized unfrozen water in Mf. These results suggest that chitin hydrolysates suppress the denaturation of Mf through enhancement of the interaction between the hydration sphere of the Mf and equatorial OH groups of chitin hydrolysate.

CHITOSAN AFFECTS TRANSGLUTAMINASE-INDUCED SURIMI GELATION

Effect of chitosan on barred garfish (Hemiramphus far) surimi gel was studied in the presence of EDTA and microbial transglutaminase (MTGase). An increase in breaking force of surimi gels added with 1.0% prawn shell chitosan indicated the gel enhancing effect of chitosan on the heat-induced gelation of fish myofibrillar proteins. However, gel-forming ability of surimi containing chitosan was inhibited in the presence of EDTA, especially at higher concentration. Therefore, the enhancing effect of chitosan was possibly mediated through the action of endogenous transglutaminase (TGase) during setting, resulting in the formation of protein-protein and protein-chitosan conjugates. In general, addition of MTGase remarkably increased both breaking force and deformation of surimi gel (P<0.05). However, enhancing effect of MTGase was retarded in the presence of chitosan, resulting in lower magnitude of breaking force and deformation (P<0.05). Scanning electron microscopy showed that chitosan particles were uniformly dispersed in the gel matrix. A tightly associated gel network was formed in surimi containing MTGase, whereas a large number of voids were noted in gels with EDTA. These results suggest that chitosan acted as a surimi gel enhancer in combination with endogenous TGase in fish muscle, but hindered gel formation in the presence of MTGase.

Effect of sugar on changes in the denaturation of fish myofibrillar protein and the state of water during frozen storage

Effect of sugar on changes in the denaturation of fish myofibrillar protein and the state of water during frozen storage

Effect of added concentration of chitin hydrolysate on denaturation of fish myofibrillar protein and the state of water during frozen storage

Effect of added concentration of chitin hydrolysate on denaturation of fish myofibrillar protein and the state of water during frozen storage

Effect of sodium alginate on changes in the denaturation of fish myofibrillar protein and the state of water during frozen storage

Effect of sodium alginate on changes in the denaturation of fish myofibrillar protein and the state of water during frozen storage

Effect of Chitin Isolated from Crustaceans and Cephalopods on Denaturation of Fish Myofibrillar Protein and the State of Water during Frozen Storage

Effect of Chitin Isolated from Crustaceans and Cephalopods on Denaturation of Fish Myofibrillar Protein and the State of Water during Frozen Storage

Analysis of fish and squid myofibrillar proteins by capillary sodium dodecyl sulfate gel electrophoresis: actin and myosin quantification

A capillary electrophoretic method for the separation and quantification of fish and squid myofibrillar proteins was developed. The method uses sodium dodecyl sulfate and β-mercaptoethanol for solubilization and analysis of myofibrillar protein subunits. The separation of the different polypeptides is achieved by the sieving effect of the gel inside the capillary. A calibration curve for myosin heavy chain and actin UV absorbance quantification of these proteins was developed.

Gel Forming Additive Effects on Properties of Thermally Induced Minced Fish Gel

ABSTRACTWater‐binding capacity (WBC) and hardness of minced chum salmon flesh decreased after 3 mo frozen storage. Additives with phosphate, carrageenan, soy protein isolate increased the WBC of fresh and frozen minced chum salmon flesh, and the texture profile analysis (TPA) hardness of the thermally‐induced myofibrillar protein gels of salmon flesh. TPA hardness was a useful index for characterizing sensory hardness of the cooked minced products. The observation of gel structure by scanning electron microscope showed additives modified the microstructure of fish myofibrillar protein gel and the ability of the gel network to bind water, thus resulting in minced flesh with different WBC and gelling ability.