Mackerel Surimi Research Articles

Effect of dietary fibre and MTGase on the quality of mackerel surimi gels

AbstractBACKGROUND: The effects of microbial transglutaminase (MTGase; 5 g kg−1) and dietary fibre (inner pea fibre and chicory root inulin, 20 and 40 g kg−1) on gels from surimi made with Atlantic (Scomber scombrus) and chub mackerel (Scomber japonicus) were studied with the purpose of achieving a better understanding of the underlying phenomena and improving gels.RESULTS: MTGase addition improved textural properties (namely, cohesiveness increased from 0.19–0.41 to 0.59–0.72) and increased pH and water‐holding capacity (WHC). Moreover, MTGase reduced the elastic and viscous modules and darkened gels; protein solubility declined, meaning greater protein aggregation, according to electropherograms. MTGase had no unequivocal effect upon the gels' microstructure. Pea fibre increased hardness (an increase of almost 60% with 40 g kg−1) and related parameters, the elastic and viscous modules and WHC. Pea fibre reduced extractable protein in sodium dodecyl sulfate and urea (in the absence of MTGase) as well. Scanning electron microscopy revealed different structures for gels containing pea fibre. Regarding inulin, it worsened textural quality and WHC.CONCLUSION: A combination of MTGase and pea fibre can improve a poor quality surimi. Copyright © 2009 Society of Chemical Industry

Effect of oxidised tannic acid on the gel properties of mackerel ( Rastrelliger kanagurta) mince and surimi prepared by different washing processes

Effect of oxidised tannic acid (OTA) at different levels (0, 0.25, 0.50 and 0.75% of protein content) on the gel properties of mackerel ( Rastrelliger kanagurta) mince and surimi prepared by different washing processes was investigated. Breaking force and deformation of gels varied with washing processes and concentrations of OTA. The gel of alkaline-saline washing process surimi (ASWPS) added with 0.25% OTA had the increases in breaking force and deformation by 166.2 and 45.9%, respectively, compared with that of conventional washing process surimi (CWPS) without OTA addition. Those increases were associated with the lowered expressible moisture content. Electrophoretic studies revealed that the greater polymerisation was found in ASWPS added with 0.25% OTA. Slight retention of myosin heavy chain (MHC) with lowered trichloroacetic acid (TCA) soluble peptide contents was observed in ASWPS gel added with 0.25% OTA, suggesting the decreased degradation induced by indigenous proteases. The microstructure of ASWPS gels became more ordered, compact and denser with the addition of 0.25% OTA. The use of OTA in conjunction with alkaline-saline washing process could improve the properties of gel from mackerel surimi without adverse effect on sensory properties.

Rheological properties of HPMC enhanced surimi analyzed by small- and large-strain tests—II: Effect of water content and ingredients

In order to develop a hydroxylpropylmethylcellulose (HPMC) enhanced surimi product with desirable flow properties and gel-forming ability at higher water contents, thermal scanning rheological monitor (TSRM) and rotational viscometer were used to perform small- and large-strain tests, respectively, to investigate the rheological properties of HPMC enhanced surimi at various water contents. The apparent viscosity, fluid consistency index and yield stress of HPMC powder enhanced surimi were higher than those of the HPMC sol enhanced sample. The addition of HPMC improved flow properties, decreased the shear thinning properties, and increased the G′ of surimi. Disintegration was offset by HPMC thermal gelation in these stabilized surimi gels. The critical water content (CWC) of water holding capacity for horse mackerel surimi was around 82% and, when surimi water content exceeded CWC, we found marked decrease in G′ and gel strength. While adding HPMC enhanced the G ′ , gel strength did not improve. Furthermore, the absorption of water in the surimi by potato starch granules is more effective than by HPMC. The water molecules desorption of HPMC during thermal gelation caused excess water to be exuded from the kamaboko.

Thermal gelation behaviors of surimi protein mixed with Hydroxypropylmethylcellulose

This study examined the thermal galation characteristics of myofibrillar protein (MP) and salt-ground horse mackerel surimi that had been mixed with hydroxypropylmethylcellulose (HPMC). Analysis, using thermal scanning rigidity monitor and differential scanning calorimetry, demonstrated that thermal gelation begins in the thermo-reversible HPMC gel used in this study at approximately 60°C. In the rescanning test, first scanning diagrams showed similar pattern, but second scanning diagrams were rather diverse between MP and MP/HPMC mixture. The addition of HPMC increased rigidity of salt-ground surimi and modified the thermal gelation during the heating process, suggesting that certain enhancing effect of gelation occurred when the mixture of MP and HPMC was heated. In the annealing test, the addition of HPMC lowered the breaking force, but increased the gel strength of surimi due to a substantial increase in deformation. Although the strong cross-linking between the two components might not occur during the gelling process, HPMC gel formed at high temperature occupies some space in thermal gel by interacting with proteins and resulted in a combinative gel with a higher rigidity and gel strength at higher temperature.

Physicochemical properties, gel-forming ability and myoglobin content of sardine (Sardinella gibbosa) and mackerel (Rastrelliger kanagurta) surimi produced by conventional method and alkaline solubilisation process

Characteristics and gel properties of sardine and mackerel surimi produced by conventional washing process and alkaline solubilising process were investigated. The decrease in Ca2+-ATPase activity with the changes in the surface hydrophobicity was found in surimi produced by alkaline solubilising process (p<0.05), suggesting the denaturation of protein induced by this process. The alkal-ine solubilising process with prewashing could remove myoglobin most effectively from sardine muscle, whereas the process without prewashing resulted in the greatest myoglobin removal in mackerel muscle (p<0.05). Surimi conventionally prepared by water or NaCl washing showed the gel with greater breaking force and deformation than that from alkaline solubilising process (p<0.05). The hig-her expressible moisture was found in the gels of surimi pre-pared by alkaline process, indicating the poor water holding capacity of the gel matrix. The highest whiteness was found in the gel of sardine surimi produced by alkaline process with prewashing but the highest whiteness was obtained in the gel of mackerel surimi washed with distilled water.

Transglutaminase effects on gelation capacity of thermally induced beef protein gels

Transglutaminase (TG) is an enzyme that catalyzes an acyl-transfer reaction between the γ-carboxyamide group of peptide or protein-bound glutaminyl residues, and primary amines. TG action on protein molecules, causes a cross-linking and polymerizing effect of these latter, through ε-(γ-glutamyl)lysine bonds. This TG-mediated protein cross-linking creates drastic physical changes in protein-rich foods. This research objective, was to evaluate the microbial transglutaminase (MTGase) effect on beef gel texture. Time and incubation temperature, enzyme concentration, and Chilean jack mackerel ( Trachurus murphyi) surimi addition effects, were studied. Beef gel quality, was assessed by measuring gel strength and cooking yield. Additionally, SDS-PAGE electrophoresis and ε-(γ-glutamyl)lysine bond analysis by HPLC were carried out on the gels. MTGase addition, significantly increased gel strength. The optimal attributes were observed at 60 °C after 2 h and 0.5% w/w of MTGase, with a gel strength 88% higher than the control-gel. Jack mackerel surimi and MTGase incorporation in beef gels, significantly increased gel strength and cooking yield. SDS-PAGE analysis revealed that the myosin heavy chain (MHC) content decreased and that the cross-linked protein amount, apparently increased with time and MTGase addition. Proteolysis was also observed. ε-(γ-Glutamyl)lysine bond production also increased as a function of incubation time and MTGase concentration. These results, suggest that it is possible to improve mechanical properties of beef gels by adding MTGase and jack mackerel surimi, thus increasing their potential utilization in minced based products.

NIR spectroscopy: A non-destructive fast technique to verify heat treatment of fish-meat gel

Attempts have been made to assess previous heat treatment of fish-meat gels prepared from walleye pollack and horse mackerel surimi, since surimi-based products have been gaining popularity for their protein quality, law fat content and convenience in consumption. Visible–NIR spectra of gels (30–90 °C) were collected from 650 to 1100 nm with a surface interactance fibre optic accessory. Partial least squares (PLS) and multiple linear regression (MLR) techniques were employed for data analysis. Spectral changes upon heat treatment were related to the heating temperature which reflected the changes in the environment of the secondary structure due to the denaturation of proteins, and to changes in the state of water. A promising linear relationship ( R = 0.98) was observed between NIR-predicted temperatures and the actual heating temperatures with prediction error of 1.85 °C.

Comparison of horse mackerel and tilapia surimi gel based on rheological and 1H NMR relaxation properties

Horse mackerel and tilapia surimi were subjected to six different heat and pressure treatments in order to compare gelation characteristics of easy- and difficult-setting gels, that is, temperature dependence, by observing rheological properties and microscopic molecular mobility. The stress-relaxation and proton spin-spin relaxation time (1H T 2) of water were measured for all treated gels. Horse mackerel gel demonstrated higher elasticity, large distribution of the stress-relaxation process, and smaller water 1H T 2 than tilapia in both heat and pressure treatments. The water 1H T 2 was steeply increased in the pressure treatment at around 294 MPa for both fishes. In contrast, the 1H T 2 rarely changed in the heat treatment in spite of the considerable change in rheological properties. From the experimental results, it is considered that the gelation of horse mackerel (easy setting) surimi is induced by highly unfolding are re-aggregation of protein, which contributes to the formation of a strong network structure compared with tilapia in both heat and pressure treatments, and that pressure treatments hardly improve the gel strength of tilapia (difficult setting) surimi. The water 1H T 2 measurement was used effectively in order to study gelation characteristics of easy- and difficult-setting fish through observing its molecular dynamics.

Combination model for the spatial partition of surimi protein and hydroxylpropylmethylcellulose

The objectives of this study were to investigate the combination model of hydroxylpropylmethylcellulose (HPMC) added with surimi protein gel. HPMC forms and addition timing apparently affected the structural geometry of the combination gel matrix and resulted in the variation in rigidity, thermal stability and gel strength. Upon viewing of the scanning electron microscopy (SEM) photographs, the horse mackerel surimi displayed a large holes and smooth protein matrix, while, the HPMC added surimi displayed a porous or rough structure. According to thermal gelation and microstructure analysis, the filling effect existed in HPMC added surimi. HPMC existed as dispersed particles in HPBC (HPMC powder added before chopping) and HPDC (HPMC powder added during chopping) surimi. HPMC remained soluble in the interstitial fluid of the surimi gel matrix in HGBC (HPMC gel added before chopping) and HGDC (HPMC gel added during chopping) surimi. These four ‘simple’ filled gels turned to ‘complex’ filled gels during the process of thermal gelation caused by certain interaction of the gelled HPMC and protein gel matrix. HGAC (HPMC gel added after chopping) surimi formed an interpenetrating structure together with a gelling protein and a gelling HPMC.

The effect of whitening agents on the gel‐forming ability and whiteness of surimi

SummaryThe effect of different concentrations of the whitening agents, calcium carbonate, titanium dioxide and soybean oil, on the gel‐forming ability and whiteness of a mixture of bigeye snapper and mackerel surimi was investigated. The whiteness of the surimi gels increased as the concentration of all whitening agents increased (P &lt; 0.05). Titanium dioxide was a good whitening agent and it had no detrimental effects on gel‐forming ability, while oil reduced the gel breaking force and deformation. The addition of calcium carbonate did not result in a marked increase in whiteness, but it did increase the breaking force and deformation to some extent. The different whitening agents showed different influences on the whiteness and gelling characteristics of surimi gel.

Glycosylation modification improved the characteristics of recombinant chicken cystatin and its application on mackerel surimi.

The recombinant and glycosylation chicken cystatins were expressed and secreted in the broth of Pichia pastoris X-33 transformant with apparent molecular masses (M) of 14 and 55 kDa, respectively. The glycosylation cystatin (glycocystatin) contained a polysaccharide chain that was composed of 50 DP of mannose residues. Because of the polymannosyl chain, the inhibitory ability in glycocystatin was 90.8% of recombinant cystatin. In addition to freeze-thawing stability, the thermal and pH stabilities as well as the susceptibility of glycocystatin were also enhanced. Both cystatins could improve the mackerel surimi gel by inhibiting the gel softening, which was derived from the hydrolysis of catheptic cysteine proteinases. Despite the additional amount of glycocystatin (8 units), twice that of recombinant cystatin, the 40 and 15% increases in breaking force and deformation of gels were also observed. Accordingly, the surimi gel was further improved by enhancing the stability of chicken cystatin.

Thermophysical properties of silver hake and mackerel surimi at cooking temperatures

Thermal diffusivity values obtained using a transient method both from heating and cooling information and apparent specific heat of surimi made from silver hake and mackerel as a function of temperature (60–110 °C) and added potato starch content (3% and 7%, w/w) were determined. The water content of all samples was kept constant at about 77% (w/w) in order to determine the effect of starch. Thermal diffusivity and apparent specific heat of all samples increased with temperature. The effect of temperature on diffusivity was found significant ( p=0.001) in all samples at temperatures above 85 °C. This effect may be caused by structural changes as temperature is raised. Thermal diffusivity increased with temperature more rapidly in samples with high levels of starch than in those with no starch. However, thermal diffusivity of silver hake surimi preset at 40 °C for 30 min did not show a significant increase ( p<0.05) over the temperature range studied. Thermal diffusivities calculated from cooling and heating data were significantly different ( p<0.05). The differential scanning calorimetry (DSC) thermograms of silver hake and mackerel surimi showed three endothermic peaks. When starch was added to surimi samples an endothermic peak having a large area was observed, which overlapped the third highest temperature peak of surimi samples. No significant shifts in the endothermic peaks of myofibrillar proteins were detected with increasing starch content. Transition temperatures for starch–surimi system were higher than those for starch–water system. There were deviations in the apparent heat capacity function calculated from DSC measurements in surimi samples containing starch. These are attributed to gelatinization of starch and modification of water structure.

Microbial Transglutaminase and Recombinant Cystatin Effects on Improving the Quality of Mackerel Surimi

ABSTRACT: Effects of microbial transglutaminase (MTGase), recombinant cystatin, or their combination on the gel properties of mackerel surimi were investigated. The addition of MTGase caused the cross‐linking of myosin heavy chain (MHC) and substantially increased the gel strength (from 536.6 to 2012.4 g × cm), while the recombinant cystatin could effectively prevent the MHC degradation and gel softening during the production of mackerel surimi‐based products. Combined use of MTGase and recombinant cystatin revealed synergistic effectiveness on improving the quality of mackerel surimi (increased from 435 to 2438 g × cm, set at 45 °C for 20 min).

Enhanced expression of chicken cystatin as a thioredoxin fusion form in Escherichia coli AD494(DE3)pLysS and its effect on the prevention of surimi gel softening.

The DNA encoding chicken lung cystatin was ligated into a thioredoxin-pET 23a+ expression vector and transformed into Escherichia coli AD494(DE3)pLysS. A high level of soluble recombinant thioredoxin-cystatin (trx-cystatin) was expressed in the cytoplasm of the E. coli transformant. As compared with recombinant cystatin (trx-free), a 38.7% increase of inhibitory activity in the soluble fraction was achieved by introducing the trx fusion protein. Trx-cystatin was purified to electrophoretical homogeneity by 3 min of heating at 90 degrees C and Sephacryl S-100 chromatography. The molecular mass of trx-cystatin was 29 kDa, which was the expected size based on its composition of recombinant trx (16 kDa) and chicken cystatin (13 kDa). The purified trx-cystatin behaved as a thermally stable and papain-like proteinase inhibitor comparable to either recombinant or natural chicken cystatins. The inhibitor could inhibit the gel softening of mackerel surimi.

Thermogelation in plasma protein-added surimi of horse mackerel and the changes in its physical characteristics in stewed products

Plasma protein concentrate (PPC) was added as a gelation aid material to horse mackerel surimi, and changes in the physical properties of surimi during heating and reheating in a soy sauce-based liquid seasoning; this is, stewing, were investigated. The rigidity of 2% PPC gel was lower than 2 kPa, and yet the addition of PPC increased the surimi rigidity markedly. Differential scanning calorimetry analysis showed that the existence of PPC promoted protein molecular aggregation. During the stewing process, the decrease in water content and water activity of kamaboko sections with PPC added was slower than that of kamaboko without PPC. The gradually hardened matrix resulted in a higher cutting force, cohesiveness (chewiness) and reduced deformation in stewed products.

High-level production of recombinant chicken cystatin by Pichia pastoris and its application in mackerel surimi.

A high level of the secreted form of recombinant chicken cystatin was expressed in Pichia pastoris X-33 by chromosomal integration of multiple copies of an expression cassette containing chicken cystatin under the control of glyceraldehyde-3-phosphate dehydrogenase promoter. The inhibition ability of the recombinant for papain-like proteinase was found to correspond to those of natural chicken cystatin. The recombinant cystatin substantially inhibited the proteolysis of myosin and gel softening, which consequently improved the gel properties of mackerel surimi.

Quality Improvement of Mackerel Surimi with NADPH‐Sulfite Reductase from Escherichia coli

ABSTRACT:The application of NADPH‐sulfite reductase, produced from Escherichia coli, on mackerel surimi was investigated. The activity of this reductase was very stable. There was about 70%, 80%, and 90% activity left even after 8–wk storage at 25 °C and 12–wk storage at 4 or ‐30 °C, respectively. Increase in mackerel‐surimi gel properties containing reductase was consistent with the amounts of reactive sulfhydryl groups detected. SDS‐PAGE indicated that NADPH‐sulfite reductase could reconstitute myosin heavy‐chain and increase soluble actomyosin. From the data obtained, E. coli NADPH‐sulfite reductase effectively improved the gel properties of mackerel surimi.

Inhibition of Thermal Degradation of Mackerel Surimi by Pig Plasma Protein and L‐kininogen

ABSTRACT: Use of purified L‐kininogen to prevent actomyosin (AM) degradation by cathepsins, and pig plasma proteins to reduce mackerel modori were investigated. Myosin heavy chain (MHC) degradation in AM containing various cathepsins was significantly inhibited by purified L‐kininogen. The texture of mackerel gel increased to 2‐fold and 1.7‐fold in breaking force (g) and deformation (cm) separately after adding 1% pig plasma protein. SDSPAGE showed that degradation of MHC in mackerel surimi was significantly reduced after 1% pig plasma protein addition at several temperatures. It suggested that the pig plasma protein containing L‐kininogen could effectively reduce the modori phenomenon of mackerel surimi during processing.

Effect of non-muscle protein on the thermogelation of horse mackerel surimi and the resultant cooking tolerance of kamaboko

Four kinds of non-muscle proteins, including liquid egg white, plasma protein concentrate, wheat gluten and whey protein concentrate were added as gelation aid materials to horse mackerel surimi. Decrease in on-set temperature of first heat gelation and resolution degree were observed in the surimi containing these non-muscle proteins. Addition of plasma protein clearly increased the surimi rigidity, reflecting its excellent thermogelation ability. Addition of the proteins also enhanced the gel strength and cooking tolerance of heated surimi products (kamaboko). Plasma protein effectively increased the gel strength of kamaboko, giving a firm and elastic gel, which still had high gel strength in cooking under 70°C. Addition of the proteins also inhibited the browning of kamaboko during cooking.

Effects of mackerel cathepsins L and L-like, and calpain on the degradation of mackerel surimi

SUMMARY: During surimi processing, the total cathepsins B+L+L-like activities in minced, leached and NaCl-ground meats were 2.45, 2.07 and 1.77 units/g, respectively. There was still 77% activity left even after 8 weeks storage at –20°C. High calpain and calpastatin activities in the crude enzymes from frozen mackerel surimi suggested that they were difficult to remove during processing and very stable during frozen storage. The SDS-PAGE analysis indicated that the optimal conditions for the hydrolysis of myosin heavy chain (MHC) were 40–55°C, pH 5.5–7.0 for cathepsins L and L-like and pH 7.0–7.5 for calpain. The gel strength of surimi treated with calpain did not decrease significantly, but the strength of those treated with purified cathepsins L and/or L-like decreased significantly (P < 0.05) after 2 h incubation at 55°C. These results suggested that cathepsins L and L-like left in surimi had MHC-degrading ability which consequently caused gel softening during setting at 40–55°C.