应用新型添加剂的大甲鲹鱼糜生产新工艺

对大甲鲹(Megalaspis cordyla)鱼糜生产新工艺进行了研究.通过钙离子(Ca<'2+>)漂洗液漂洗和使用凝胶增强剂两个措施增强大甲鲹鱼糜的凝胶形成能力.先对漂洗液硬度对鱼糜凝胶强度的影响进行单因素试验,之后再对非酶型凝胶增强剂(命名为GRA1)、转谷氨酰胺酶(TGase)、鸡蛋白3种单一凝胶增强剂对鱼麋凝胶强度增加效果进行比较,又对鸡蛋白添加量、CRA1添加量进行二因素三水平的随机区组复配设计试验.试验得出了最优化的工艺条件:漂洗工艺中,漂洗液Ca<'2+>浓度为30mmol/L;凝胶增强剂使用工艺,选择用1.5%鸡蛋白复配0.30%GRA1作为复合凝胶增强剂.在该工艺务件下,大甲鲹鱼糜凝胶强度(二次加热法)为832.37g/cm,是传统工艺的9.34倍;复合凝胶增强剂的添加荆成本比单独使用TGase节约46%.     

淡水鱼鱼糜性质研究

采用清水漂洗、盐水漂洗和碱水漂洗、钙离子、热处理方法对草鱼、白鲢鱼糜进行试验,阐明诸因素对草鱼、白鲢鱼糜凝胶性能的影响,为生产鱼糜制品提供合理的工艺参数、研究表明,草鱼2次清水与1次盐水漂洗凝胶性能较好,鲢鱼鱼糜的最佳钙离子质量分数为0 5%。     

不同处理条件下鲢鱼糜凝胶水分状态和微观结构的特征

为探讨超高压改善低盐鲢(Hypophthalmichthys molitrix)鱼糜凝胶品质的机制,利用低场核磁共振(low field nuclear magnetic resonance,LF-NMR)、差示扫描量热法(differential scanning calorimeter,DSC)、傅里叶红外光谱(fourier transform infrared spectroscopy,FT-IR)以及扫描电镜分析比较了超高压低盐鱼糜凝胶[300 MPa,1.5%氯化钠(NaCl)]与常压低盐鱼糜凝胶(0.1 MPa,1.5%NaCl)以及常压普通鱼糜凝胶(0.1 MPa,2.5%NaCl)在水分状态和微观结构上的差异。DSC结果表明超高压低盐鱼糜凝胶可冻结水的冰点降低,结合水含量(17.58%)较低盐对照组(10.89%)显著提高;LF-NMR表明超高压低盐鱼糜凝胶弛豫时间T21、T23和T24左移,不易流动水的含量(76.65%)较低盐对照组(67.29%)提高了9.39%;超高压处理能使低盐鱼糜凝胶形成光滑、连续、均匀的三维网络结构。因此,超高压处理(300 MPa,10 min)能够提高低盐鲢鱼糜凝胶结合水含量、改善微观结构。     

加工工艺对鱼糜及其制品品质影响的研究进展

随着我国渔业养殖产业迅猛发展,对渔业资源进行精深加工已成为水产业发展的一个必然趋势。鱼糜制品是水产品精深加工程度较高的产品之一,其蛋白质含量丰富,口感独特,易于储藏,深受消费者喜爱,发展前景良好。本文根据大量国内外文献资料,通过大量实例选取原料的选择、漂洗工艺、斩拌工艺、加热工艺及辅料配方等5个方面阐述其影响鱼糜品质的机理,并解释说明了能改善鱼糜凝胶性能并提高鱼糜及其制品品质的生产工艺流程,为鱼糜及鱼糜制品的加工提供理论及技术依据。     

钙离子添加量对未漂洗海鲈鱼糜凝胶特性的影响

为探明钙离子(Ca~(2+))能否提高未漂洗海鲈鱼糜的凝胶品质,为海鲈鱼糜生产提供新方法。以海鲈鱼为原料,比较氯化钙(CaCl_2)不同添加量(0.01～0.08 M)对采肉后未经漂洗工序直接制成海鲈鱼糜的凝胶强度、质构特性(TPA)、持水力、白度、微观结构等的影响,并与传统方法制备的海鲈鱼糜进行比较。结果表明Ca~(2+)对未漂洗的海鲈鱼糜品质有显著影响(P0.05);CaCl_2的添加可显著提高未漂洗海鲈鱼糜凝胶强度、TPA、持水力和白度,使鱼糜组织结构紧密均匀;当CaCl_2添加量在0.02 M时,未漂洗的海鲈鱼糜的凝胶特性(凝胶强度7 364.21 g·mm、持水力88.93%、硬度421.8 g、弹性10.03 mm、胶着性229.5 g、咀嚼性22.21 mJ、白度86.72)与传统鱼糜品质相近,其效果最好;而当CaCl_2添加量达到0.08 M时,Ca~(2+)与鱼肉蛋白过度交联,形成钙桥结构,造成凝胶强度和硬度增加、弹性下降。研究表明,适量添加Ca~(2+)可使海鲈鱼糜不需经过漂洗工序而达到传统漂洗生产鱼糜的品质,这为开发营养流失少、节水、节能的海鲈鱼糜加工提供理论和技术支撑。     

漂洗工艺和抗冻剂对几种西非鱼鱼糜凝胶特性和色泽的影响

研究了不同漂洗工艺和抗冻剂对几种西非鱼鱼糜冻藏后凝胶特性和白度的影响，结果发现，用NaHCO3，柠檬酸和CaCl2溶液进行漂行可明显提高鱼糜制品的硬度和凝胶强度，但对弹性的影响不大，因而凝胶强度的增加主工是由硬度的变化引起的，用NaHCO3和NaClO漂洗可明显提高鱼糜的白度，尤其是对红色肉含量较高的鱼类，抗冻剂能明显提高鱼糜制品的凝胶强度。     

加工冷冻鱼糜的新型设备及工艺

在鱼糜制作中，鱼体经前处理、采肉漂洗后，以往都是先脱水再过滤，这种工艺方法因脱水后水分含量低，存在着过滤困难、鱼肉温升高、杂物不易除尽、凝胶形成能降低等缺点。作者自行设计研制了成套鱼糜生产设备，采用新型分级机（Ｒｅｆｉｎｅｒ）及先分级精制、再压榨脱水的生产工艺。本文探讨这一设备及工艺在规模性生产冷冻鱼糜的条件下的主要性能，供鱼糜生产企业参考。材　料　　１．原料试验原料重４．５ｔ，原料鱼有金线鱼、白姑、海鳝等６种；规格为３０～１５０ｇ／尾，平均８５ｇ／尾。原料购自广西北海，１２月１０日上午１０ｖ０…     

白鲢鱼糕加工工艺的优化研究

利用低值的淡水鱼--白鲢为主要原料加工传统鱼糕,以感官品质和凝胶强度为指标,通过单因素和正交试验对白鲢鱼糕关键工艺进行优化.结果表明,白鲢鱼糕最佳工艺组合为:加热(汽蒸)时间10 min、擂溃时间15 min、两次清水漂洗和1次0.5%盐水漂洗.该工艺条件的白鲢鱼糕不仅感官品质好,且具有较大凝胶强度.此项研究对低值白鲢资源开发利用有着重要的意义.     

几个影响蓝圆鲹等低值鱼鱼糜凝胶性能因素的探讨

本文介绍影响蓝圆鲹等低值鱼鱼糜的凝胶性能的几种因素,如原料鲜度、漂洗、斩拌,加热方式和添加淀粉等。试验结果表明,在适宜的工艺条件下蓝圆鲹等低值鱼的凝胶性能能满足一般鱼糜制品的粘弹性要求。     

鲫鱼和罗非鱼的凝胶特性值研究

本文通过对日本罗非鱼和鲫鱼及其冷冻鱼糜的凝胶特性值进行一系列测定,得出其最佳的凝胶形成温度分别是35℃和40℃,凝胶析出温度是60℃。凝胶形成值碱盐漂洗法高于清水漂洗法,分别是清水漂洗的2及1.7倍左右。只有在50℃以下凝胶,二段加热的第二次加热才有提高凝胶形成能和增加白度的作用。冰鲜四天,k值11.0的鲫鱼其凝胶形成能平均仅为k值3.2活鲫鱼的40％,对于鲜度差的鱼采用一段的高温加热法(30′90℃)为佳。罗非鱼的凝胶形成能高于鲫鱼,大约是鲫鱼的1.5倍。鱼糜的耐冻性罗非鱼比鲫鱼强,添加5％砂糖或5％环糊精及0.2％多磷酸盐都能够有效地抑制两种冷冻鱼糜的变性。     

Study on Gel Properties of Silver Carp (Hypophthalmichthys molitrix) and White Croaker (Argyrosomus argentatus) Blended Surimi at Different Setting Conditions

Gel properties of blends of surimi from silver carp and white croaker set for a range of times and at different temperatures were evaluated for breaking force, breaking distance, and whiteness. Total protein content was 12% in all samples, and the concentration of white croaker surimi protein in the blends was designed at 0, 10, 20, 30, and 40%. The blended surimi had greater gel strength than either of the two types of surimi alone. Breaking force and breaking distance after setting were also significantly higher than that of the blended surimi cooked directly without setting. The blended surimi exhibited less modori than either of the two types of surimi alone heated to 50°C. The whiteness values of the blended surimi were significantly higher than that of white croaker alone. These results indicate there are advantages to be gained in utilizing surimi from freshwater silver carp in blends with surimi from marine captured white croaker which is becoming limited in supply.     

5种淡水鱼鱼糜凝胶基本特性研究

文章以凝胶特性、肌原纤维蛋白化学键以及脂质、磷脂含量等为指标,研究了5种淡水鱼[黄颡鱼(Pelteobagrus fulvidraco)、草鱼(Ctenopharyngodon idellus)、鳙(Aristichthys nobilis)、鲮(Cirrhinus molitorella)、鲢(Hypophthalmichthys molitrix)]鱼糜第一段和第二段加热的凝胶性能变化。结果显示,第一段加热鱼糜的凝胶强度、硬度、咀嚼性、白度、持水性显著小于第二段(P<0.05),但凝胶弹性和内聚性差异不明显。表面疏水性均在第二段加热后显著增大,且增加程度差异显著(P<0.05);对于二硫键,鳙和黄颡鱼两段加热的凝胶样品差异不显著(P>0.05)。第二段加热凝胶的脂质质量分数介于38.24~76.45 g·kg^-1,磷脂质量分数介于1.929~3.452 mg·g^-1。     

Algal biomass accrual in relation to nutrient availability and limitation along a longitudinal gradient of a karst riverine system

Textural property of surimi products is a prime factor in determining the acceptability of consumer as well as market value. Gelatin is one of the most popular biopolymers widely used in food industry as gelling agent with the unique textural properties. Therefore, the addition of gelatin along with the use of protein cross-linkers could be a means to modify the texture of surimi gel, which can fit the demand of consumers. Surimi from the threadfin bream (Nemipterus bleekeri) was added with bovine gelatin (BG) and bovine/fish gelatin mix (BFGM; 1:1, 2:1, 1:2, 4:1, and 1:4) at 10% protein substitution in combination with and without microbial transglutaminase (MTGase) at 1.2 units/g surimi. Textural properties, whiteness, expressible moisture content, protein pattern, and microstructure and sensory properties of gels were determined. When MTGase at 1.2 units/g surimi was incorporated, the increases in breaking force and deformation were noticeable in both surimi gels, with and without 10% BG added ( p < 0.05). On the other hand, surimi gels added with BFGM at all bovine/fish gelatin ratios had the higher breaking force and deformation, compared with that added with BG, when MTGase was incorporated. Addition of BG or BFGM lowered the expressible moisture content and whiteness of surimi gel ( p < 0.05). Based on SDS-PAGE, band intensity of myosin heavy chain and actin of surimi gel decreased when surimi gel was added with all gelatins, regardless of MTGase addition. The microstructure study revealed that surimi gel network became finer and denser with the addition of MTGase (1.2 units/g surimi), but the coarser and irregular structure was obtained when gelatin was incorporated. Gelatin, especially bovine/fish gelatin mix, at an appropriate level could be used as the protein additive in surumi gel in conjunction with MTGase in order to improve the textural and nutritive properties of the products.     

TG酶催化过程中鲢肌原纤维蛋白凝胶性能的变化

为探究转谷氨酰胺酶（TG酶）催化过程中,鲢肌原纤维蛋白凝胶性能的变化,进一步提升鲢鱼糜制品特性和营养价值。对不同催化时间（0、15、30、60 min）后鲢肌原纤维蛋白凝胶的交联度、凝胶强度、白度、持水性、微观结构及消化特性变化进行了分析。实验结果表明,TG酶诱导蛋白胶凝后,蛋白凝胶交联度显著提高。在TG酶催化过程中,随交联时间的延长,白度值增加、持水性提高。通过扫描电镜分析发现凝胶网络孔径变小,结构变得更加致密。在催化时间30 min下,交联度、白度值及持水力显著提高,弛豫时间T22显著减小。TG酶催化后的蛋白凝胶在消化初始阶段水解程度较低,因为交联度提升,蛋白网络结构越来越致密,降低了胃蛋白酶对其水解位点的可及性。蛋白消化90 min后,网络遭到破坏,导致其水解速率明显提高。以上结果说明,在适当的交联时间下,有助于提升蛋白凝胶的凝胶特性。该研究为TG酶对鱼肉制品品质及消化特性的改善提供了实验依据。     

Cryoprotective effects of shrimp head protein hydrolysate on gel forming ability and protein denaturation of lizardfish surimi during frozen storage

ABSTRACT:   The effects of shrimp head protein hydrolysate (SHPH) from three species of shrimp (northern pink shrimp [ Pandalus eous ], endeavour shrimp [ Metapenaeus endeavouri ], black tiger shrimp [ Penaeus monodon ]) on gel forming ability and protein denaturation of lizardfish surimi during frozen storage at −25°C were evaluated. The quality of lizardfish surimi with 5% (dried matter) of any of the three SHPH or sodium glutamate (Na-Glu) was examined in terms of gel strength, whiteness, Ca-ATPase activity and the amount of unfrozen water, comparing with those of surimi without additive as the control. The residual Ca-ATPase activity and gel strength of surimi with SHPH were higher than those of the control throughout 180 days of frozen storage, regardless of shrimp species. The highest effect was found in surimi with Na-Glu. The gel strength and Ca-ATPase activity found a high positive correlation. The addition of SHPH to surimi also increased the amount of unfrozen water by approximately 1.29–1.36 fold higher than the control, however kamaboko gels of the control was significantly whiter. From these results, freeze-induced denaturation of lizardfish muscle protein could be lessened by the addition of SHPH, resulting in a high gel strength and Ca-ATPase activity.     

Effect of β-Glucan Stabilized Virgin Coconut Oil Nanoemulsion on Properties of Croaker Surimi Gel

Effects of virgin coconut oil (VCO) nanoemulsion stabilized by β-glucan and β-glucan solution at final β-glucan levels of 5–20% (based on solid weight of surimi) on croaker surimi gel were comparatively studied. Increases in breaking force, deformation, and fracture constant were found in surimi gel containing VCO nanoemulsion stabilized by 5% β-glucan, whereas a decrease in all properties was observed as the level of β-glucan in nanoemulsion increased. The addition of β-glucan solutions led to continuous decrease in breaking force, deformation, and fracture constant, compared to the control. Addition of both β-glucan stabilized nanoemulsion and β-glucan solutions resulted in decrease in viscoelastic moduli. Power law model represented viscoelastic behavior of all the gels. Expressible moisture content decreased, while whiteness increased with the addition of β-glucan-stabilized nanoemulsion, compared with gel containing VCO. However, both expressible moisture content and whiteness increased with the addition of β-glucan solutions, at all levels used. Addition of β-glucan-stabilized nanoemulsion resulted in finer gels compared to the control gel added with only VCO. Generally, overall likeness score increased for gel containing VCO nanoemulsion stabilized by 5% β-glucan. The surimi gel containing both medium chain fatty acids and β-glucan, functional ingredients, could be developed as a new product.     

Effects of pH and NaCl on Gel Strength of Pacific Whiting Surimi

The effects of varying concentrations of salt and pH on the gel strength of Pacific whiting (Merluccius productus) surimi were investigated. Surimi gels were made with and without the protease inhibitor beef plasma protein (BPP). Gel strength was measured by torsion and reported as shear stress and shear strain. In general, surimi gels increased in gel strength with increased pH. Stress increased to a greater degree than strain about pH 7. Water holding capacity values increased up to pH7 and than leveled off. Surimi gels made with low salt (0.9%) or not salt had greater stress values that the higher salt surimi gels in the alkaline pH range. The results demonstrated that the effects of salt and pH are interactive on gels strength for Pacific whiting surimi     

Comparison of Conventional Washing Processing and pH Shift Processing on Gelation Characteristics of Bighead Carp (Aristichthys nobilis) Muscle Proteins

In this study, gelation characteristics of bighead carp (Aristichthys nobilis) protein isolates prepared by pH shift processing were investigated as compared with those of surimi prepared by conventional wash processing. Results showed that the gel from alkali-aided protein isolate exhibited a higher breaking force than that from conventional washed surimi (p < 0.05). However, the gel from conventional washed surimi had higher whiteness (p < 0.05) and lower expressible moisture (p < 0.05). The rheological study showed that protein isolates exhibited different storage modulus and loss tangent patterns from conventional washed surimi during heating. Acid-aided processing could lead to higher denaturation and dissociation for fish muscle myosin and a coarser gel network from the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) pattern and the scanning electron microscopy (SEM). Overall, there is a potential to apply pH shift processing, especially alkali-aided processing, to extract more proteins from bighead carp muscle for the production of surimi-based food.     

Effects of Olive Leaf Powder on Mechanical Properties of Heat-Induced Surimi Gel

The effects of addition of olive leaf powder (OLP) to surimi on the mechanical properties of surimi gel were investigated. The OLP contained a high polyphenol content of 7% (w/w). The breaking stress and breaking strain of surimi gel increased with increasing OLP concentration. The addition of 0.3% OLP increased the breaking stress of surimi gel by 80% and the breaking strain by 38%. The addition of 2.0% OLP resulted in a 100% increase in the breaking strain. The OLP gels had finer and denser protein networks than the control gel, probably due to integration of additional crosslinks into the protein networks via polyphenols or their derivatives. Although the addition of OLP had a detrimental effect on whiteness of surimi gel, OLP is still a useful functional ingredient for improving mechanical properties of surimi gel products in which the color is not an important quality.     

Quality Characteristics of Tilapia Surimi: Effect of Single Washing Cycle and Different Washing Media

Surimi was prepared by washing with single washing cycle with cold water (T-1), alkaline saline (0.2% NaHCO₃ and 0.15% NaCl; T-2) solution, and with calcium chloride and salt (0.2% CaCl₂ and 0.1% NaCl; T-3), respectively, and compared with conventional washed (CW) surimi. T-2 exhibited significantly (p ≤ 0.05) increased moisture content, which correlated with increased yield, pH and also significantly decreased lipid and ash content. A significant (p ≤ 0.05) decrease in expressible moisture content was also observed in T-2, which suggested higher water holding capacity compared to other treatments. Heat-induced surimi gels exhibited highest L* (p ≤ 0.05), followed by surimi in all the treatments. In the case of L*, T-1 showed highest lightness, followed by T-2, which was comparable to CW. The lowest myoglobin content was exhibited by CW surimi (p ≤ 0.05), which is due to repeated washings. T-2 gel showed higher elasticity, texture, and overall acceptability than others (p ≤ 0.05), except for the whiteness. In all the aspects, T-2 was comparable with CW. Washing with one cycle of T-2 solution can not only improve the quality of surimi but can reduce the wastage of water that is released into the environment without further treatment.