Effect of pressure-shift freezing treatment on gelling and structural properties of grass carp surimi

The damage of conventional freezing (CF) to the quality of surimi products is an urgent problem in the food industry. In the study, the effect of different freezing treatments [CF, pressure shift freezing (PSF), pressure-shift freezing pretreatment (Pr-PSF), unfrozen control] on gelling properties [gel strength, texture profile analysis (TPA), color], water-holding capacity (WHC) and protein structure characteristics of the grass carp surimi gel were evaluated and compared. Compared with other freezing treatment groups, surimi gel strength was increased three to four times after PSF treatment, which was mainly caused by the change in the microstructure and the WHC of the surimi gel. The study showed that PSF treatment could significantly improve the quality of the surimi gel and overcome the negative effect of freezing on the surimi gel. This indicates that PSF technology has a wide application prospect in the surimi gel processing industry, food processing and related material fields.Industrial relevance: PSF can enhance the commodity value of low-value freshwater fish products and has potential in surimi gel new product development. The development of new products and the use of new resources are very important in addressing the global food crisis and resource shortages. In addition, PSF units with self-cooling systems offer opportunities for scale-up and commercialization.     

鲢鱼新鲜度对鱼糜凝胶品质的影响

通过对4 ℃条件下鲢鱼死后10 h感官特性、pH值和僵直指数的变化过程以及鲢鱼死后不同时间鱼肉的挥发性盐基氮（total volatile basic nitrogen,TVB-N）值和Ca2＋-ATP酶活性变化的检测,研究鲢鱼肉新鲜度对鱼糜凝胶品质的影响。结果表明：鲢鱼在死后2～3 h开始进入僵直期,鱼体僵直指数升高,pH值下降;随着鲢鱼死后时间的延长,鱼肉的TVB-N值显著升高,Ca2＋-ATP酶活性显著降低。采用死后不同时间的鲢鱼肉制作的鱼糜凝胶,其凝胶强度、保水性和白度均有显著差异,其中以新鲜鲢鱼为原料制作的鱼糜凝胶的凝胶强度最高,而鱼糜凝胶的保水性和白度在鱼肉的僵直期最差。     

紫菜粉添加对鱿鱼鱼糜凝胶特性及其蛋白结构的影响

为改善秘鲁鱿鱼鱼糜凝胶品质,分析紫菜粉添加量对鱿鱼鱼糜凝胶感官评分、色泽、凝胶强度、持水性、微观结构及其肌原纤维蛋白组成和二级结构的影响,探究紫菜粉改善鱿鱼鱼糜凝胶品质的机理.结果表明:紫菜粉对鱿鱼鱼糜凝胶白度影响显著,添加后鱿鱼鱼糜凝胶色泽偏黄绿色;随着紫菜粉添加量的增加,鱿鱼鱼糜凝胶强度和持水性显著增加,并在添加量...     

鱼糜副产物酶解物对冻融鲢鱼鱼糜品质的影响

为了解鱼糜加工副产物（鱼头、鱼骨、鱼鳞、鱼鳍等）酶解物的添加对冻融鲢鱼鱼糜品质及凝胶特性的影响,对酶解物的体外抗氧化性及反复冻融鱼糜的盐溶性蛋白含量、巯基含量、Ca2＋-ATP酶活性、表面疏水性、凝胶特性、凝胶持水性及色泽进行研究。结果表明：与其他酶相比,经胰蛋白酶及碱性蛋白酶酶解后,鱼糜加工副产物酶解物的体外抗氧化活性最强;与对照组及蔗糖添加组鱼糜相比,鱼糜加工副产物酶解物的添加能够有效减缓反复冻融后鱼糜肌原纤维蛋白的冷冻变性及氧化速率,鱼糜的盐溶性蛋白含量、巯基含量、Ca2＋-ATP酶活性较高,表面疏水性较低;同时,鱼糜加工副产物酶解物的加入增强了鱼糜凝胶的初始凝胶特性及持水性,并能够有效延缓鱼糜凝胶破断力、凹陷度及凝胶强度的劣变,改善鱼糜凝胶的持水性。     

乳化鱼油对冻藏期间狭鳕鱼糜热凝胶持水性和冰结晶形成的影响

评估乳化鱼油对冻藏期间狭鳕鱼糜热凝胶持水性和冰结晶形成的影响。鱼糜经盐擂后,加入5%鱼油经乳化制得乳化鱼糜热凝胶。随后用快速冻结和慢速冻结2 种方式冻结样品并评估其在冻藏期间热凝胶品质的变化。研究结果表明：与对照相比,乳化热凝胶在冻藏期间的解冻损失和压榨损失均有降低。显微观察结果显示经3 个月冻藏后乳化热凝胶内的冰结晶平均粒径与其对照相比均有减小,其中快速冻结乳化样品为7.2 μm,对照样品为13.1 μm,慢速冻结乳化样品为13.7 μm,对照样品为31.2 μm。以上结果表明乳化鱼油可能对冻藏期间的热凝胶的冰结晶形成和其分布的影响而导致其持水性不同。     

离子强度和pH值对肌原纤维蛋白热诱导凝胶特性的影响

以肌原纤维热诱导凝胶的保水性和质构特性,包括硬度、弹性、内聚性、胶黏性、回复性为指标,考察离子强度和pH值对猪背最长肌肌原纤维热诱导凝胶特性的影响.结果表明,离子强度和pH对凝胶不同特性的影响存在差异,综合各种指标,离子强度为0.5,pH值在6.5和7.0之间有利于形成较好的凝胶.不同条件下凝胶形成的机制可能存在差异.凝胶的硬度与弹性、胶黏性和保水性相关性显著(P＜0.05),可以作为重点考察的指标.     

基于蛋白质结构和理化性质的鱼糜蛋白-油脂相互作用

通过添加不同质量分数大豆油和猪油，研究油脂对金鲳鱼鱼糜凝胶理化性质和蛋白结构的影响。在油脂质量分数范围内（0%～20%）,8%的猪油与大豆油使鱼糜白度、持水性、凝胶强度、储能模量（G’）和感官评价显著增加。而油脂质量分数高于8%后，鱼糜凝胶强度、持水性、G’等指标下降。与大豆油相比，含有猪油的鱼糜凝胶（8%）的指标更优。扫描电子显微镜结果显示，油脂不仅以颗粒填充的方式占据蛋白间的空隙，还在表面形成界面蛋白膜，通过蛋白丝与蛋白基质结合。研究表明油脂在鱼糜凝胶中所产生的作用是由油脂-界面蛋白膜-蛋白质共同作用而形成。拉曼光谱图谱表明，添加油脂会使蛋白质α-螺旋相对含量下降，β-折叠相对含量先上升后下降。而大豆油的加入，使得鱼糜凝胶的无规卷曲相对含量也明显增加，而猪油处理组中无规卷曲相对含量变化不如大豆油组。大豆油和猪油的添加均导致鱼糜凝胶的蛋白侧链疏水基团暴露。这些结果表明油脂的存在会改变鱼糜蛋白的微环境和分子结构，进而影响鱼糜凝胶的理化性质。当猪油质量分数为8%时，鱼糜凝胶表现出更优的性质。     

面筋蛋白和大米蛋白对鲢鱼鱼糜凝胶特性的影响

面筋蛋白和大米蛋白均可以明显提高鲢鱼鱼糜的凝胶强度和持水性,降低其蒸煮损失率和横向弛豫时间(T_2)。但是与大米蛋白相比,面筋蛋白在改善鲢鱼鱼糜凝胶特性方面效果更加显著。当面筋蛋白添加量为3%时,鱼糜凝胶的破断力、破断距离、凝胶强度和持水性分别为669.0 g、12.2 mm、8 162.0 g·m和89.8%,与对照组(未添加蛋白)相比分别增加了79.8%、37.2%、147.0%、11.6%;而蒸煮损失率为8.51%,与对照组相比降低了19.7%。且此时的凝胶横向弛豫时间T_(23)和T_(24)分别为42.4 ms和156.0 ms。3%的面筋蛋白促使鲢鱼鱼糜凝胶形成十分致密的空间三维网络结构,使其具有较高的凝胶强度和持水性,但是由于面筋蛋白带有浅黄色,所以鱼糜凝胶的白度有轻微下降。     

芋头添加物对金鲳鱼鱼糜凝胶的影响

研究芋头添加物对金鲳鱼鱼糜凝胶品质的影响,分析添加不同量芋头原浆和芋头淀粉时,金鲳鱼鱼糜凝胶的白度、凝胶强度、持水性、水分含量、横向弛豫时间T2的变化规律。结果表明：添加芋头原浆,金鲳鱼鱼糜凝胶的感官品质较好;添加芋头淀粉,金鲳鱼鱼糜凝胶的凝胶强度和持水力较好;芋头添加物可以降低其白度。低场核磁共振结果显示,随着芋头添加物的加入,金鲳鱼鱼糜凝胶的弛豫时间T22、T23减少,弛豫时间T21增大,峰面积S21、S22增加,峰面积S23减少,凝胶中自由水的流动性减弱。     

添加微细鲽鱼鱼骨泥对金线鱼鱼糜凝胶品质的影响

以鲽鱼骨为研究对象,首先采用湿法超微粉碎技术将其加工成微细骨泥,再将其添加到金线鱼鱼糜制品中开发高钙鱼糜制品,从鱼糜溶胶pH值、肌原纤维蛋白Ca2＋-ATP酶活力、凝胶强度、质构、持水性、色泽、凝胶溶解度、微观结构方面探讨添加不同质量分数（2.5%～12.5%）鱼骨泥对鱼糜制品凝胶品质的影响。结果显示：添加微细鱼骨泥不影响鱼糜正常凝胶的pH值;较低质量分数（不超过5.0%）时,鱼骨泥中的Ca2＋可以激活鱼糜溶胶中肌原纤维蛋白的ATP酶,显著提升Ca2＋-ATP酶活力;鱼糜凝胶的凝胶强度、质构、持水性、色泽指标均在添加质量分数5.0%鱼骨泥时达到最高值,而凝胶溶解度达到最低值。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析和扫描电子显微镜观察结果表明,添加质量分数2.5%～5.0%鱼骨泥一定程度上促进了肌球蛋白重链（myosin heavy chain,MHC）的交联,可以促进鱼糜凝胶形成致密均匀的网状结构,过量添加则会影响MHC交联和凝胶网络致密性。     

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。     

鳕鱼皮的添加对鱼糜凝胶特性及其蛋白质结构的影响

目的 研究添加黑线鳕鱼(Melanogrammusaeglefinus)皮对鱼糜凝胶特性和蛋白质结构的影响.方法 以傅里叶变换红外光谱法和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳技术的分析方法,探究黑线鳕鱼皮不同添加比率对鱼糜凝胶的凝胶强度、质构、持水性、pH和蛋白质分子组成及其二级结构的影响规律.结果 当鱼皮添加比率为5％...     

Optimal blending of differently refined fish proteins based on their functional properties

Two different mixtures (Alaska pollock surimi with grass carp fish protein isolate (FPI) and grass carp surimi with grass carp FPI) were investigated for their compatibility and functionalities. As the proportion of FPI increased, it was observed surface hydrophobicity and surface reactive sulfhydryl (SRSH) content increased significantly, indicating the degree of fish protein unfolding prior to gelation was much higher than surimi alone. Comparable results were shown as measured by storage modulus (G′) in oscillatory dynamic rheology, demonstrating the gelling temperature was reduced when the proportion of FPI increased. Effects of mixing surimi and FPI on gel functionality (hardness, cohesiveness, and whiteness) exhibited a linear pattern when the proportion of surimi was larger than or equal to that of FPI. However, there were no linear relationships when the proportion of FPI exceeded that of surimi.

Practical applications

Commercial surimi has been successfully used in the Western world over 30 years. Unlike surimi which is a refined fish myofibrillar protein composite, fish protein isolate (FPI) is a refined composite of myofibrillar protein and sarcoplasmic protein. The former is made by avoiding any chemical/physical denaturation, while the latter can be made by inducing chemical denaturation and renaturation with pH shift. Even though FPI is not currently available in a commercial scale, it has a great potential to replace all or a part of surimi for the manufacture of fish protein gel products. This study reveals how to optimally mixed these two differently refined fish proteins based on their functional properties. The results suggested that blending surimi and FPI may be feasible only when the proportion of FPI does not exceed 50%.     

4种鱼糜加工漂洗液回收蛋白对罗非鱼鱼糜凝胶特性与质构的影响

目的 探究4种回收水溶性蛋白对罗非鱼鱼糜凝胶特性及质构的影响。方法 分别将等电点沉降法回收蛋白、海藻酸钠单一絮凝剂回收蛋白、壳聚糖单一絮凝剂回收蛋白和海藻酸钠-壳聚糖复合絮凝剂沉降回收蛋白以0%、5%、10%、15%、20%掺入罗非鱼鱼糜制备鱼肠,比较各样品在凝胶强度与全质构分析(texture profile analysis, TPA)参数上的差异,包括硬度、胶着性、咀嚼性、内聚性与弹性。结果 4种回收蛋白替代会对凝胶强度产生不利影响,通过等电点沉降法回收的蛋白对凝胶强度的影响最大,凝胶强度持续下降,最低达1708g·mm;以复合絮凝剂回收蛋白的掺入对原凝胶强度的影响最小,通过替代5%鱼糜,凝胶强度降为3833 g·mm。当用壳聚糖单一絮凝剂回收蛋白掺入5%时,与原鱼糜制品的TPA参数最接近,表现为硬度2505 g,胶着性1788 g,咀嚼性192.3 mJ,且内聚性和弹性也没有表现出明显差异。结论 这4种回收蛋白均以5%的添加量替代罗非鱼鱼糜时,制品凝胶强度在企业的可接受线性范围内,综合凝胶强度与TPA参数,以壳聚糖单一絮凝剂回收的蛋白替代产生的影响最小,可为回收鱼糜蛋白这一资源...     

Changes of water state and gel characteristics of Hairtail (Trichiurus lepturus) surimi during thermal processing

This study examined the changes of water state and gel characteristics of Hairtail surimi during thermal processing including two steps. The results showed that there were four content of water in Hairtail surimi gels. Water‐holding capacity (WHC) and T₂₃ relaxation time of water and gel strength increased from 47.01 to 78.97% and from 64.23 to 51.52 ms, respectively, and whiteness decreased from 63.87 to 55.22 during the entire thermal processing. Meanwhile, the texture properties including hardness, gumminess, and chewiness declined from 402.42 to 130.41 g, from 294.39 to103.70 g, and from 233.68 to 43.60 g, respectively, during the first step, and then increased markedly during the second step from 130.41 to 2,301.87 g, from 103.70 to 1,250.99 g, and from 43.60 to 978.51 g, respectively. Furthermore, the WHC and textural profile had positive correlation, and changes in protein secondary structure were interesting, with the α‐helices decreasing significantly from 26.40 to 14.12%, while the β‐sheet and the random coil structure increasing significantly from 36.28 to 44.03%, and from 10.89 to 14.31%, respectively, and β‐turn structure increasing form 26.44 to 27.98% during the first step and then declining markedly during the second step, moreover β‐sheet had a fine positive correlation with WHC hardness and chewiness. Overall, dense, porous and compact three‐dimensional network gel structure gradually formed. In a word, during thermal processing. WHC of Hairtail surimi increased, and protein secondary structure of protein became orderly, and a fine, dense gel formed during thermal processing. Water is considered as the highest and most important chemical constituent in surimi products. During surimi gelation, water molecules exist as bulk water and motionally restricted water on the protein surface. In order to gain more insights into the surimi heating‐induced gelation processing, and improve the surimi gel properties, and give same advice to manufacturing enterprise, this work was conducted to study the structural changes of protein and water state during surimi gelation processing and performed along with the monitoring of the texture, WHC and other physical characteristics of surimi gel, as well as the microstructure of surimi gel.     

不同低温冻融循环对鱼糜品质与加工特性的影响

为研究不同低温条件下的冻融循环对鱼糜加工品质变化的影响.将制得的鱼糜样品定量分装成3组,分别置于4、?18、?35℃冰箱中,并模拟5次冻融循环.期间,分别进行各组冻融鱼糜的流变特性、凝胶特性、水分变化(低场核磁共振、冷冻损失率、解冻损失率、蒸煮损失率和持水性)、质构特性,并结合微观结构观察,以综合判定贮藏温度对鱼糜冻融...     

Investigation of sweet potato starch as a structural enhancer for three‐dimensional printing of Scomberomorus niphonius surimi

Three‐dimensional printing (3DP) of surimi requires a structural modifier to achieve a stable construct. This work investigated the effect of addition of sweet potato starch (0–10% wt/wt) on the physical properties (rheological properties, gel strength, water‐holding capacity [WHC], and microstructural characteristics) of surimi gels and the 3D printed behavior of these gels. The results showed that as the starch content increased, the viscosity of the starch–surimi mixture decreased facilitating the flow of the surimi out of the printer nozzle. The surimi gel with 8% sweet potato starch concentration showed good gel strength (2,021.70 g mm), WHC (82.39%), microstructural characteristics, and less cooking loss (1.95%). A comparison of the traditional surimi preparation method with 3DP showed that the surimi gel prepared by a 3D printed construct was softer in gel strength (1,398.65 g mm) and lower in hardness (945.17 g) although showing slightly higher cooking loss (6.76%) and lower WHC (72.66 g) than the conventional product. The results suggest that sweet potato starch can be effectively used as a structural enhancer for 3DP complex‐shaped surimi.     

罗非鱼与海水鱼制备混合鱼糜的凝胶特性研究

通过研究罗非鱼、五种海水鱼(海鲈鱼、黄花鱼、金鲳鱼、红三鱼、马鲛鱼)、鸢乌贼鱼糜的凝胶特性,筛选凝胶特性强的鱼糜与罗非鱼鱼糜复配,以提高罗非鱼混合鱼糜的凝胶特性。通过比较五种海水鱼和鸢乌贼鱼糜的凝胶特性(凝胶强度,白度,盐溶性蛋白含量,巯基含量),得到海鲈鱼的凝胶特性较好,凝胶强度为4569.27 g·mm,盐溶性蛋白含量为48.17 mg/mL。将海鲈鱼与罗非鱼混合,当海鲈鱼添加量为25%时,混合鱼糜的凝胶强度、盐溶性蛋白含量、白度分别为2585.10 g·mm、29.73 mg/mL、72.62%,比单一的罗非鱼鱼糜分别提高了27.3%、63.8%、5.2%,而巯基含量无显著影响。因此,添加25%海鲈鱼能够较大程度地提高罗非鱼鱼糜的凝胶特性,为罗非鱼混合鱼糜制品的开发奠定了基础。     

The effect of egg albumen on the viscoelasticity of crab sticks made from Alaska Pollock and Pacific Whiting surimi

The influence of the amount of egg albumen contained as a gelation agent in crab sticks made from Alaska Pollock or Pacific Whiting surimi on their viscoelastic properties was examined. Dynamic oscillatory and transient tests allowed a variety of parameters to be measured in order to establish the intensity of the interactions in the protein network which characterize the gel strength. This physical property is fundamental for the nominal quality texture and eating quality of surimi and surimi-based seafood analog products (surimi seafood). Three different egg albumen contents around the nominal value (2%) were studied, namely: 1.5, 2 and 2.5%. The viscoelastic gel strength (A_n) and gel strength (S) values obtained in the frequency sweep and creep tests, respectively, were quite consistent. Increasing the protein content of the surimi increased the gel strength of both types of crab sticks (p < 0.05). The optimum egg albumen content was found to be about 1.5% for Alaska Pollock and 2% for Pacific Whiting surimi. Based on these results, the industry could use less albumen in making crab sticks from Alaska Pollock surimi, which surpasses Pacific Whiting surimi in quality.     

典型加工条件下鱼糜肌原纤维蛋白品质变化规律及调控方法研究进展

鱼糜制品（鱼丸、鱼糕、蟹肉棒等）因为其健康营养、方便快捷等特点而深受消费者欢迎，具有广阔的市场前景。鱼糜制品是基于鱼糜肌原纤维蛋白的胶凝性能所形成的弹性凝胶体，其加工工序包括斩拌、加热、添加外源物等。因此，鱼糜肌原纤维蛋白在典型加工条件下发生结构以及功能特性的变化会影响鱼糜制品的品质。本文主要综述了鱼糜肌原纤维蛋白在物理场（加热、斩拌）、化学场（pH值、离子强度）、生物场（酶、微生物）等典型加工条件下的结构及功能特性变化规律及调控方法，以期为进一步发展鱼糜制品加工业提供理论依据。