Gel‐forming ability of surimi from grass carp (Ctenopharyngodon idellus): influence of heat treatment and soy protein isolate

The effects of setting conditions and soy protein isolate (SPI) on textural properties of surimi produced from grass carp were investigated. Effects of setting temperature, setting time and protein concentration on the breaking force and distance were evaluated and compared utilizing response surface methodology. Models for breaking force and breaking distance of grass carp surimi were established. Protein concentration was the major factor affecting the gel strength of grass carp surimi. Breaking force and distance of grass carp surimi gels decreased with increase of protein ratio from SPI at 30 °C and 40 °C for 60 min setting and heating at 85 °C for 30 min, but the breaking force obtained for addition of 100 g kg^?1 SPI protein to grass carp surimi was higher than that for surimi alone at 60 °C for 60 min incubation and heating at 85 °C for 30 min. Copyright © 2005 Society of Chemical Industry     

Gel properties of surimi from silver carp (Hypophthalmichthys molitrix) as affected by heat treatment and soy protein isolate

The effects of setting conditions and soy protein isolate (SPI) on textural properties of surimi produced from silver carp were investigated. Effects of setting temperature, setting time and protein concentration on the gel strength were evaluated and compared utilizing response surface methodology. Models for breaking force and breaking distance of silver carp surimi were established. The total protein content was 13.4% in all experimental samples. Setting temperature and protein concentration were the major factors affecting the gel strength. In the range of the additive SPI protein (10–40%), breaking force and distance of silver carp surimi gels decreased when the protein ratio of SPI was increased in the total protein at 30 and 40 °C for 60 min setting and heating at 85 °C for 30 min, but the breaking force obtained for 90% surimi protein plus 10% SPI protein was higher than surimi alone at 50 °C for 60 min incubation and heating at 85 °C for 30 min.     

Effect of soy protein isolate on gel properties of Alaska pollock and common carp surimi at different setting conditions

The effects of soy protein isolate (SPI) on the gel properties of different grade Alaska pollock and common carp surimi at different setting conditions were evaluated and compared. Breaking force and distance of gels decreased with increasing SPI concentrations in direct cook (85 °C for 30 min) and in cook after setting at 30 °C for 60 min conditions. The effect of SPI on gel strength of common carp surimi was less than in Alaska pollock surimi. The breaking force obtained for addition of 10% SPI to Alaska pollock surimi was higher than for surimi alone when cooked after incubation at 50 °C for 60 min. Addition of SPI decreased the whiteness and increased the yellowness of the gel. The gel structure showed that the addition of SPI modified the microstructure of the fish protein gel, thus resulting in surimi with different gelling properties. Copyright © 2004 Society of Chemical Industry     

不同加热条件对复合鱼糜凝胶特性的影响

本研究考察了鲢鱼鱼糜和带鱼鱼糜形成的复合鱼糜的破断力和凹陷深度在不同凝胶化条件下的变化规律。实验中各处理组的蛋白含量均为12%,其中蛋白比例为100%鲢鱼鱼糜,100%带鱼鱼糜,以及鲢鱼鱼糜和带鱼鱼糜的蛋白含量比例为9:1,8:2,7:3和6:4。结果表明:在凝胶化温度为30℃时,复合鱼糜的破断力均高于鲢鱼鱼糜,在鲢鱼鱼糜和带鱼鱼糜比例为7:3时破断力和凹陷深度均达到最大值,此时也高于带鱼鱼糜;而在凝胶化温度为40℃时,带鱼鱼糜添加量为40%时,破断力和凹陷深度达到最大,此时的凝胶特性优于带鱼鱼糜。带鱼鱼糜和鲢鱼鱼糜在50℃时均出现凝胶劣化现象。当带鱼鱼糜添加量为10%时,复合鱼糜对鲢鱼鱼糜和带鱼鱼糜的凝胶劣化均有显著的抑制作用。     

鲢鱼鱼糜蛋白质凝胶特性的研究

研究了鲢鱼鱼糜在不同的加热条件下 ,其凝胶的色泽、强度及显微结构的变化。结果表明 ,鲢鱼鱼糜在 60℃时达到较理想的色泽 (白色 ) ,较佳的凝胶条件为 ,先经过 3 5～ 40℃、60min的凝胶化 ,再经过 85℃、3 0min加热。在 5 0℃加热时 ,出现凝胶劣化现象     

Comparison of Gel Properties of Surimi from Alaska Pollock and Three Freshwater Fish Species: Effects of Thermal Processing and Protein Concentration

ABSTRACT The gel strength of surimi made from Alaska pollock, common carp, grass carp, and silver carp was determined and compared for different incubation temperatures and periods. Gel strength and setting of the 3 freshwater fish species were inferior to that of Alaska pollock. Effects of the protein concentration, heating temperature and heating period on the gel strength were evaluated and compared utilizing the response surface methodology. Models for the breaking force and breaking distance of the surimi of the 4 species were established. Protein concentration was the major factor affecting the gel strength. Effects of heating temperature and heating period had differed somewhat among the surimi of the 4 species.     

超高压耦合热处理对鳙鱼鱼糜凝胶特性和水分迁移的影响

研究不同压力（100~500 MPa）耦合热处理（40 ℃/30 min,90 ℃/20 min）对鳙鱼（Aristichthys nobilis）鱼糜凝胶特性及水分迁移的影响,考察了不同处理条件下鳙鱼鱼糜的凝胶强度、持水性（WHC）、白度、质构、微观结构、SDS-PAGE电泳及水分迁移的变化,并进行相关性分析。研究发现,超高压耦合热处理能显著改善鳙鱼鱼糜的凝胶特性。超高压条件为300 MPa/15 min的压力耦合热处理（记为300PH）样品的凝胶强度和不易流动水单位质量峰面积（A22）显著性高于其他处理组（p<0.05）。与传统二段热处理样品相比,300PH样品的凝胶强度和WHC分别提高了88.40%、4.75%。与鱼糜凝胶的凝胶强度具有高度相关性的指标分别是破断强度、凹陷深度、硬度、弹性、胶着性、咀嚼性和A22。结合水单位质量峰面积（A21）与鱼糜凝胶强度具有中度相关性,这些表明300PH样品形成致密的凝胶网络结构,锁住更多结合水,限制不易流动水向自由水迁移,从而改善鱼糜凝胶的凝胶特性。该研究旨在为超高压技术鱼糜凝胶制品加工中的产业化应用、优质淡水鱼鱼糜制品的加工提供数据参考。     

不同食用蛋白的添加对鲤鱼鱼糜流变和凝胶特性的影响

目的:研究大豆分离蛋白(soybean protein isolated,SPI)、乳清分离蛋白(whey protein isolate,WPI)、花生分离蛋白(peanut protein isolate,PPI)的添加对鲤鱼鱼糜流变和凝胶性质的影响。方法:利用流变仪、质构仪、色差计等对添加不同蛋白鱼糜的弹性模量、黏性模量、凝胶强度、破断强度、凹陷深度、持水性以及白度进行测定,并采用相关性分析法研究各指标之间的相互关系。结果:不同添加量的SPI、WPI和PPI均能有效地改善鱼糜的弹性模量、黏性模量、破断强度、凝胶强度和持水性,但会降低破断深度和白度,但各测定指标间存在显著相关(p<0.05)。SPI和PPI的添加对鱼糜的流变性、破断强度、凝胶强度的提高效果更好,添加量为8%时,鱼糜的凝胶强度均达到最大值,其中SPI组可达3806.70 g·mm,比对照组增加了34.63%;WPI对鱼糜的保水性效果最好,添加量为8%时,失水率仅为12.6%;白度随着蛋白添加量的增加而降低,其中PPI组与WPI组引起的白度降低较少,且差异不显著(p>0.05)。结论:在实际鱼糜制品的生产中,应根据产品的特征选择适合的蛋白种类和合理的添加量,来提高鱼糜制品的品质。     

Characteristics of surimi and kamaboko from sardines

Sardines of varying freshness (1 to 3 days in ice) were manually or mechanically processed into fish mince and surimi using 1 to 3 washing steps. Standard kamaboko gels were prepared by grinding thawed surimi with 3% NaCl and 5% potato starch, stuffing into sausage casings, holding at 37°C for 30 min and cooking at 90°C for 50 min.
Three washing steps decreased the yield of washed fish mince (21-27 g per 100 g of whole fish), and the protein recovery (50-55% of that present in the unwashed mince), but caused efficient lipid removal (80%) leading to surimi containing only 0.2-1.4% lipid. The texture and colour of the final kamaboko were also improved.
The texture parameters (folding score, rigidity, elasticity index and gel strength) of kamaboko prepared from very fresh sardines were markedly enhanced by gel setting during incubation at 37°C for 30 min or 4°C for 24 hr. Incubation at 60°C for 30 min led to soft, coarse gels. Omitting potato starch or replacement by spray dried egg white had little effect on texture.
The texture of kamaboko prepared from less fresh sardines was less firm and elastic, did not improve when incubation was carried out at 37 or 4°C before cooking, and was softer and coarser after incubation at 60°C. Partial or total replacement of potato starch by egg white, soy protein isolate or bovine serum albumin markedly improved the texture. Egg white also increased the colour lightness.     

乳清浓缩蛋白对竹荚鱼鱼糜凝胶化和凝胶劣化的影响

采用质构分析法、扫描电子显微镜等方法研究乳清浓缩蛋白对竹荚鱼鱼糜凝胶劣化的抑制作用。结果表明：添加乳清浓缩蛋白(WPC)能显著改善竹荚鱼鱼糜在30℃凝胶化时的凝胶特性,并且添加量为5%(质量分数),加热时间为5h时,竹荚鱼鱼糜的凝胶特性最佳;添加WPC能显著抑制竹荚鱼鱼糜在50℃凝胶劣化现象,WPC的添加量为5%时,抑制效果显著,添加量为10%时,抑制效果最佳;WPC的添加量低于0.5%时,对竹荚鱼鱼糜凝胶色泽的影响不明显;添加量超过1%时,竹荚鱼鱼糜凝胶的白度显著降低。微观结构的观察表明,添加WPC使鱼糜凝胶的结构变得更加致密,因而能增强竹荚鱼鱼糜的凝胶强度。     

Effect of protein additives, sodium ascorbate, and microbial transglutaminase on the texture and colour of red tilapia surimi gel

Beef plasma protein (BPP) and egg white, at levels of 10, 20 and 30 g kg⁻¹, and sodium ascorbate (SA) and microbial transglutaminase (MTGase), at levels of 1, 2 and 3 g kg⁻¹, were individually added into red tilapia surimi. This gel was set at 40 °C for 90 min followed by heating at 90 °C for 30 min. Gel qualities were analysed and compared with those of non-supplemented red tilapia control gel. Compared with the control, each additive significantly affected gel strength due to an increase in breaking force. Although BPP could improve texture characteristics, higher addition levels of BPP significantly affected gel whiteness. The addition of SA and MTGase were found to increase surimi gel strength and improve whiteness. Amongst all treatments, the addition of 2 g kg⁻¹ MTGase was found to provide the best gel qualities.     

Thermal syneresis affected by heating schedule and moisture level in surimi gels

ABSTRACT:  The extent of thermal syneresis in protein gelation is indicative of thermal and freeze-thaw stability as well as the network integrity of a protein gel. Thermal syneresis in Alaska pollock surimi gels was examined under different heating schedules (40 °C/20 min to 90  °C/30 min, 60 °C/20 min to 90 °C/30 min, and 90 °C/20 min to 90 °C/20 min) at varying moisture levels (80%, 82%, and 84%). The extent of syneresis and gel firming was monitored by centrifugation expressible moisture and penetration force, respectively. The occurrence of 2 distinct peaks as a function of time for both thermal syneresis and gel firming suggests that a multistage aggregation is involved in the formation of gel network. All syneresis preceded gel firming upon protein aggregation. Increasing the moisture content in the gel delayed the 2nd stage of protein aggregation. The 60 °C/20 min preheating followed by 90 °C/30 min postheating resulted in significantly greater thermal syneresis and gel weakening compared to 40 and 90 °C preheating. Changes of gel structure clearly reflected thermal syneresis when the size of water pores became smaller with initiation of network formation and progressively larger upon further heating. Thermal syneresis history during protein gelation can be used to predict thermal and freeze-thaw stability.     

Characteristics of Sarcoplasmic Proteins and Their Interaction with Surimi and Kamaboko Gel

ABSTRACT:  This study examined the effect of adding common carp sarcoplasmic proteins (Sp- P) on the gel characteristics of threadfin bream surimi and kamaboko while maintaining constant moisture and myofibrillar levels. Based on the temperature sweep test, which is involved in heating of surimi gel from 10 to 80 °C to monitor the viscoelastic properties, at temperature range of 40 to 50 °C, the decrease level (depth of valley) in storage modulus (G') thermograph was in proportion to the concentration of added Sp- P. Storage modulus (G') showed greater elasticity after adding Sp- P compared with the control without Sp- P. Furthermore, the breaking force and distance and consequently gel strength of the resultant kamaboko were improved significantly ( P > 0.05). Thus, added Sp- P did not interfere with myofibrillar proteins during sol–gel transition phase but associated with textural quality enhancement of resultant kamaboko; however, addition of Sp- P from the dark muscle of the carp decreased the whiteness of the resultant surimi. Furthermore, according to the SEM micrographs, the gel strength could not be associated with either the number of polygonal structures/mm² or the area of the polygonal structures in the kamaboko gel microstructure.     

Microbial Transglutaminase Affects Gel Properties of Golden Threadfin-bream and Pollack Surimi

ABSTRACT: The properties of surimi gels from threadfin-bream and pollack surimi set at 30 °C or 45 °C with microbial transglutaminase (MTGase) from Streptoverticillium ladakanum were determined. The optimal amounts of MTGase and setting conditions were: 0.3 unit/g surimi either at 30 °C for 90 min or at 45 °C for 20 min for threadfin-bream, and 0.2 unit/g surimi at 30 °C for 60 min for pollack. The strength of golden threadfin-bream surimi gels with 0.35 unit MTGase set at 30 °C for 90 min or 45 °C for 20 min was 3400 g cm, almost 3-fold of the control. SDS-PAGE analyses indicated that inter- and/or intramolecular cross-linking formed in the myosin heavy chain of MTGase-containing surimi gels.     

Improvement of Gelling Properties of Lizardfish Mince as Influenced by Microbial Transglutaminase and Fish Freshness

ABSTRACT:  The effects of microbial transglutaminase (MTGase) at different levels (0 to 0.8 units/g sample) on the properties of gels from lizardfish ( Saurida undosquamis ) mince set at 25 °C for 2 h or 40 °C for 30 min prior to heating at 90 °C for 20 min were studied. Breaking force and deformation of gels increased with increasing MTGase amount added ( P < 0.05). At the same MTGase level used, gels with the prior setting at 40 °C for 30 min showed a higher breaking force compared with those subjected to prior setting at 25 °C for 2 h ( P < 0.05). Sodium dodecyl sulfate-polyacrylamide gel electrophoretic study revealed that myosin heavy chain (MHC) underwent polymerization to a higher extent in the presence of MTGase. Regardless of setting condition, microstructure of gel added with MTGase was finer with a smaller void compared with that of gel without MTGase. Therefore, setting temperature affected the property of gels added with MTGase. Gel properties of mince obtained from lizardfish stored in ice for different times (0 to 10 d) with and without MTGase at a level 0.6 units/g were determined. Irrespective of MTGase addition, breaking force and deformation of all gels decreased as the storage time of lizardfish increased ( P < 0.05). The addition of MTGase was able to increase both breaking force and deformation of the resulting gel produced from lizardfish kept in ice for all storage times used. Therefore, both freshness and MTGase addition had the direct impact on gel properties of lizardfish mince.     

Comparison of Gel-forming Properties of Silver Carp (Hypophthalmichthys molitrix) Surimi Prepared in Different Seasons

ABSTRACT: The gel-forming properties of silver carp surimi made in different seasons were compared. Surimi prepared in winter and spring formed gel at 30°C, while autumn and summer surimi required a higher temperature of 40°C for gel formation. All surimi showed marked disintegration when incubated at 60°C. Ca²⁺-ATPase inactivation rate of myofibrils prepared from 4 surimi samples showed that myofibrils in autumn and summer surimi were much more stable than those in winter and spring surimi by about 10°C. These results demonstrated a close relationship between the gel-forming temperature of surimi and the thermal stability of myofibrils in surimi, namely that autumn and summer surimi containing stable myofibrils required higher temperature than winter and spring surimi for the gel formation.     

Gelation Characteristics of Paddlefish (Polyodon spathula) Surimi Under Different Heating Conditions

Gelation properties of paddlefish surimi were investigated with different heating procedures. Without pre-incubation, gel strength of paddlefish surimi increased as temperature increased from 40 to 60 °C. Pre-incubation at 40 °C caused myosin degradation and reduced gel strength by 55% compared to the control. Pre-incubation at 70 °C followed by cooking at 90 °C produced gels with maximum strength. Isothermal heating between 40 and 50 °C produced rheological transitions between 0 and 15 min. Beef plasma powder reduced myosin degradation and enhanced gelation of surimi incubated around 40 °C. These results indicated that the gel-weakening phenomenon in paddlefish surimi was due to the degradation of myosin by some endogenous protease(s).     

Fermentation of bighead carp (Aristichthys nobilis) surimi and the characteristics of fermented bighead carp surimi products

BACKGROUND: To improve the properties and functionality of bighead carp (Aristichthys nobilis) muscle, bighead carp surimi was inoculated with combinations of Saccharomyces cerevisiae, Lactobacillus and Monascus and fermented, and then bighead carp sausages were prepared. The characteristics of fermented bighead carp surimi and sausages were investigated. RESULTS: During the 24 h fermentation at 30 °C, bighead carp surimi inoculated with mixed starter cultures resulted in a rapid decrease of pH, and suppression in the growth of Enterobacteria. The bighead carp sausages exhibited better colour, taste, flavour and appearance than the control (P < 0.05). The changes in non‐protein nitrogen (NPN), free amino acid in the fermented bighead carp surimi and SDS–PAGE patterns indicated that severe hydrolysis of muscle protein had occurred during fermentation. The sausages inoculated with the mixed starter cultures gained higher scores for flavour and overall acceptability than the control. CONCLUSIONS: The characteristic of fermented bighead carp surimi and sausages can be significantly improved by fermentation with the combinations of yeast, Lactobacillus and Monascus. Copyright © 2008 Society of Chemical Industry     

Chemical Interactions and Protein Conformation Changes During Silver Carp (Hypophthalmichthys Molitrix) Surimi Gel Formation

Chemical interactions and protein conformations changes during the formation of silver carp surimi gel were studied by textural analysis, chemical methods, laser Raman spectroscopy, and circular dichrosim. The optimum setting time at 40°C was 60 min. During surimi gel formation, ionic bonds and hydrogen bonds decreased significantly (P ≤ 0.05), while hydrophobic interactions, disulfide bonds, and non-disulfide covalent bonds increased significantly (P ≤ 0.05). Hydrophobic interactions, disulfide bonds, and non-disulfide covalent bonds were the main chemical interactions maintaining the stable structure of surimi gel. Secondary structural analysis of surimi protein showed that 94.11% α-helix existed in native myosin and it partly changed into β-turn and random coil during heating. Myosin gel was made up of 33.70% α-helix, 12.40% β-turn and 53.90% random coil. These three kinds of secondary structures were the main protein conformations in surimi gel.     

Original article: Gel properties of red tilapia surimi: effects of setting condition,fish freshness and frozen storage

This study aimed to determine effects of setting condition, fish freshness and storage time of frozen surimi on properties of red tilapia surimi gel. To investigate the effect of setting condition, a combination of eight setting temperatures (35–70 °C) and four setting times (30–120 min) was used. Maximum breaking force, deformation and gel strength were obtained after the gel had been set at 40 °C for 90 or 120 min. Setting at 65 °C resulted in the lowest obtained gel strength, because of proteolytic degradation of myosin heavy chain. Increasing storage time of raw fish material in ice caused a significant decrease in gel strength of the resultant surimi gel (P < 0.05). Gels produced from surimi kept in frozen storage for up to 9 months also exhibited reduced gel strength, with a concomitant increase in the expressible drip, with increasing storage time (P < 0.05).