Quality of Fish Protein Hydrolysates from Herring (Clupea harengus)

Fish protein hydrolysates were prepared, using minced fillets and Al-calase and papain, from raw herring and from herring defatted by ethanol extraction, cooking and pressing. Physicochemical, sensory and storage properties as well as the molecular weight sizes in spraydried hydrolysates were evaluated. Fat extraction before hydrolysis reduced degree of hydrolysis. Alcalase hydrolyzed samples to a higher degree than papain. Ethanol extraction reduced fishy odor to barely detectable levels. Papain hydrolysates were more bitter than those made with Alcalase. Color and nonenzymic browning measurements indicated darkening during 3 mo storage at room temperature (～20°C).     

Biochemical and Functional Properties of Herring (Clupea harengus) Byproduct Hydrolysates

ABSTRACT: The functional, nutritional, and antioxidative properties of hydrolyzed herring and herring byproducts (head and gonad) were evaluated. All freeze-dried herring fish protein hydrolysate (FPH) powders were light yellow and contained 77% to 87% protein. The degree of hydrolysis was 18.3%, 13%, 13%, and 10.1%, respectively, for head, whole fish, body, and gonad after 75 min digestion. All FPH powders had desirable essential amino acid profiles and mineral contents. The emulsifying capacity and stability of all FPH powders were lower than those of egg albumin and soy protein; the fat adsorption was comparable to that of egg albumin. The antioxidative activity of whole herring FPH was highest, followed by that of body, gonad, and head.     

鲱鱼蛋白的营养和功能特性

介绍了鲱鱼蛋白质的制备,营养和功能特性,表明了鲱鱼蛋白能作为一种比较好的功能添加剂,营养补充剂和乳化剂。     

Effects of Brining Conditions on Weight Gain in Herring (Clupea harengus) Fillets

Salted herring is an important product category in many European countries. Reduced need for salt as a preserving agent and the increased emphasis on less salt in the human diet has changed the basis for the traditional processing of these products. This has led to significant changes in the processing conditions and in the characteristics of the salted products. In this perspective, the effects of different brine concentrations (10.0%, 16.5%, and 25.5%), brining temperatures (3.5 °C and 17.5 °C), the presence of skin or not on the fillets, and brining time (1, 2, 3, 4, and 7 d) were investigated on the weight gain (%) and final salt content (%) of herring (Clupea harengus). A significant (P < 0.001) higher weight gain of the fillets were observed at the lowest brining temperature (3.5 °C) compared with at the higher temperature (17.5 °C), independently of brine concentration and brining time. Increased brine concentration and skinning of the fillets caused the weight gain to significantly decrease (P < 0.001) and increase (P < 0.001), respectively. After 1 d of brining, the weight gain was in the range of 10% to 12% for both brining temperatures, and at the lowest temperature, the weight gain increased significantly (P < 0.001) as a function of brining time. At the higher temperature, no further significant increase in weight was observed from 1 to 7 d of brining. It is concluded that the weight gain in herring fillets brined according to the present commercial practice is significantly affected by temperature, brine concentration, brining time, and the presence or not of skin on the fillets and that the weight gain may be of high magnitude.     

Sensory Properties of Frozen Herring (Clupea harengus) from Different Catch Seasons and Locations

Freezing of herring (Clupea harengus) for human consumption is increasing in the Nordic herring industry, either onboard the fishing vessels or right after landing. The quality of frozen herring as a raw material does not only depend on the frozen storage conditions applied, but also on compositional features, something which in turn can vary with season and catching ground. To unravel the link between biological variations, basic muscle composition, and sensory properties of frozen herring, a unique herring raw material was caught by commercial fishing vessels at three locations: around Iceland, outside the Norwegian coast, and in Kattegat/Skagerrak. The samplings were done according to a specific scheme and conducted over several seasons and 2 years. The herring was converted into butterfly fillets, packed in cardboard boxes, frozen, and then stored at -20 °C or -80 °C for up to 18 mo. The sensory quality was characterized by objective sensory profiling. It was shown that two generalized sensory variables could be defined from a principal component analysis of the sensory data. Except for the expected pronounced effect from storage time, the most distinct variation followed the lipid content, which in turn varied with season. An unexpected conclusion was that catching location only had a minor affect on the changes in sensory quality of herring during frozen storage. Knowledge about how season and catching location affect herring during frozen storage will be useful for optimizing the utilization of herring for frozen storage for human consumption. Practical Application: The results of this study constitute important information for the herring processing industry when handling raw materials with different geographical and seasonal history. The reported information on a highly equal sensory quality of geographically diverse raw materials will give consumers and retailers valuable knowledge on the changes in eating quality to expect after long-term frozen storage under conditions similar to household freezers or refrigerated counters in supermarkets.     

蛋白质酶水解物功能特性及其在食品工业应用

介绍蛋白质酶水解物功能特性,总结蛋白质酶水解物在老年食品,运动员食品、减肥食品、疗效食品和普通食品中应用。     

微细化-蛋白酶解对蚕蛹蛋白营养价值和功能特性的影响

本实验采用磨球超微粉碎-蛋白酶解的方法改性处理蚕蛹蛋白,研究了改性处理后蚕蛹蛋白的营养价值和 功能特性。结果表明：微细化-酶解改性处理后蚕蛹蛋白的必需氨基酸/非必需氨基酸、必需氨基酸/总氨基酸均达到 联合国粮食及农业组织和世界卫生组织推荐模式标准,营养价值显著提升（P＜0.05）;改性处理后蚕蛹蛋白的水 解度提高了65.62%,溶解度、乳化性和起泡性分别提高了402%、187%和141%;巯基含量增加了57%,二硫键含量 降低了21%;二级结构无规卷曲含量由37.46%增加到91.33%;剂量为25 μg/mL的蚕蛹蛋白改性处理后,促小鼠脾细 胞增殖能力增加了100%,免疫能力极显著提高（P＜0.01）。     

鱿鱼皮酶解产物的功能特性

目的:研究鱿鱼皮酶解产物的功能特性.方法:根据前期实验所得最适酶解工艺,以中性蛋白酶酶解鱿鱼皮,产物经离心、过滤、冻干,研究其抗氧化活性和加工功能特性.抗氧化活性采用·OH、O2-·清除及Fe2+螯合、FRAP体系进行评价.加工功能特性包括溶解性、稳定性、起泡性及乳化性的测定.结果:鱿鱼皮酶解产物具有良好的·OH清除能力及Fe2+螯合能力,在试验范围内分别达到84.5％和89.9％;对O2-·清除能力一般,仅53.1％.由于样品纯度问题,各体系抗氧化能力及总还原力与L-抗坏血酸相比有明显差距.此外,在加工功能特性方面,除热稳定性及泡沫稳定性不甚理想,仅80.3％和54.2％外,其它特性均良好.其中溶解性97％,冷藏稳定性89.9％,起泡性240％,乳化性808.8 m2/g及乳化稳定性13.8 min.结论:鱿鱼皮来源广泛,价格低廉,其酶解产物具有较好的抗氧化活性及加工功能特性,在功能食品方面具有较大的应用价值.     

油茶籽粕蛋白功能特性及其酶解产物抗氧化活性研究

采用碱溶酸沉法提取油茶籽粕中的蛋白质,运用正交试验优化提取的最佳条件,并分析油茶籽粕蛋白功能特性及其木瓜蛋白酶水解物的抗氧化活性。结果表明,在pH 10、料液比1∶30(m/V)、提取时间3h、提取温度50℃的最佳条件下,油茶籽粕蛋白的得率为4.99%。油茶籽粕蛋白等电点在pH 5左右。乳化能力、乳化稳定性和起泡能力随p H增加呈先降后升的趋势,与蛋白溶解度密切相关。木瓜蛋白酶能有效提高油茶籽粕蛋白溶解性,其蛋白水解物对DPPH·自由基和羟基自由基均具有很好的清除能力(清除率85%),对铜离子的螯合能力大于对铁离子的螯合能力。     

Sensory properties of marinated herring (Clupea harengus) processed from raw material from commercial landings

Sensory properties of marinated herring processed from raw material from Danish commercial catches were described and related to fishing season and biological, chemical and functional properties. Herring was caught on five cruises and stored on board in tanks or ice. The sensory profile of marinated herring from the North Sea was influenced by season, and changes coincided with the cycle of feeding and spawning. During the spawning period the texture was soft and the muscle more susceptible to lipid oxidation. The texture became firmer and the fatty mouth feel stronger during the feeding period, and the odour and flavour characteristics less rancid. These effects were explained by the chemical composition and biological parameters. The sensory profile was influenced by herring size and age, but not by sex or gonad maturity; the storage method also had an effect. Herring from the Kattegat stored in ice smelled and tasted more of fresh herring and were juicier than herring from the North Sea stored in tanks. Copyright © 2004 Society of Chemical Industry     

2709碱性蛋白酶酶解鱼鳞工艺及其产物的功能特性

应用正交实验优选鱼鳞蛋白酶解的最佳条件。采用 2 70 9碱性蛋白酶 ,考察了酶量、固形物浓度、反应温度和酶解时间等因素对酶解反应的影响 ,确定最适条件。pH的选择参照了已有实验酶的最适 pH值 ,以水解度、游离氨基酸量为检测指标。结果表明 ,鱼鳞酶解宜采用碱性蛋白酶 2 70 9,用盐酸和氧化钙作软化的预处理 ,可使鱼鳞蛋白得到较高程度的水解 ,酶解最佳温度为 5 0℃ ,酶量宜采用 3 0 % ,酶解的最佳时间为 5h ,底物浓度宜选择 10 %。鱼鳞水解蛋白有很好的吸水性、乳化性、起泡性和溶解性 ;水解蛋白对羟基自由基也有很好的清除能力 ,其IC50 为 2 1mg/mL ,最大清除率为 93 6 %。     

脱色猪血红蛋白酶解产物品质及营养特性研究

研究了脱色猪血红蛋白酶解产物的功能性、风味和营养特性。在pH3.0～9.0,产物具有良好的溶解性;在pH值为7.0左右时,显示出良好的乳化性和乳化稳定性;深度酶解和脱色导致产物的持油性较差。脱色酶解产物没有苦味,其疏水值与Q准则相互吻合。酶解和脱色可以提高猪血红蛋白的营养特性。脱色猪血红蛋白酶解产物可作为食品原料加以利用。     

米渣蛋白酶解及酶解物功能性质研究

以米渣为原料,通过实验确定用复合胰蛋白酶进行限制性酶解,用酶量为1%,酶解工艺条件:酶解温度为50℃,固液比为1:5,pH为8,酶解时间3 h;并对蛋白酶解物的溶解性、乳化性及乳化稳定性、粘性、粒度分布等功能性质进行了研究,发现蛋白酶解物的功能性质较原来蛋白质有显著提高。     

Gel Properties of Surimi from Pacific Herring

Surimi produced from male Pacific herring (Clupea harengus pallusi), a by-product of the roe fishery, formed gels comparable to those formed by lower-grade pollock surimi but were darker in color. Linear relationships were found between moisture content of surimi and punch force, torsion stress, torsion strain, and compression force at failure. Addition of dried beef plasma, egg white, whey protein, wheat gluten or potato inhibitor resulted in stronger gels, although no proteolysis was detected in a control sample. Low-temperature setting, or heating at 40°C prior to cooking at 90°C resulted in stronger gels, as measured by punch test.     

大米蛋白质的酶法水解及其性质研究

本文通过三种蛋白酶催化反应动力学特性的比较，确定用碱性蛋白酶Alcalase作为水解大米分离蛋白的酶制荆，并通过正交试验分别获得高溶解性、高发泡性、高乳化性大米蛋白水解物的酶反应条件。本实验所得到的大米蛋白水解物最大溶解度为50．2％，最大发泡力为50mL，最大乳化力为73．6mL／g。     

牛骨髓蛋白及其碱性蛋白酶酶解物的功能特性比较

该研究通过水提法提取牛骨髓蛋白（Bovine Bone Marrow Protein,BBMP）,采用碱性蛋白酶制备牛骨髓蛋白酶解物（Bovine Bone Marrow Alkaline Protease Hydrolysate,BBMP-AH）,测定两者的氨基酸含量,同时比较分析结构特征、理化性质以及抗氧化活性。结果表明,BBMP-AH蛋白含量高于BBMP,BBMP-AH必需氨基酸和疏水性氨基酸含量明显的增加;紫外和红外光谱图谱表明,BBMP及BBMP-AH均显出典型的蛋白吸收峰且酶解后蛋白质二级结构发生了明显的变化;理化性质试验结果表明,BBMP及BBMP-AH的等电点在pH值6左右,远离等电点时,具有较好的理化特性,酸碱性条件下理化性质显著改善。与原蛋白相比,酶解物最高溶解性提高到94.40%、乳化性为1.24 m2/g、乳液稳定性为116.33%,持水性为3.94 g/g,持油性略有降低;BBMP-AH的抗氧化活性显著强于BBMP,均具有较强的DPPH•、•OH、O2-•、ABTS+•清除能力和总还原能力。综上,酶解处理能够改善牛骨髓蛋白理化性质,提高其抗氧化能力,延伸开发应用范围。     

核桃蛋白的分离制备及其酶解物的抗氧化特性

根据蛋白在水溶液、盐溶液、醇溶液及碱性溶液中的溶解性不同,从核桃粕中分离得到四类不同性质的蛋白组分:清蛋白、球蛋白、醇溶蛋白和谷蛋白,其中球蛋白和谷蛋白含量较高,分别为16.90%和71.40%。以脱脂脱酚粕、谷蛋白和球蛋白为原料,分别制备蛋白酶解液,以DPPH自由基清除率和蛋白质回收率为指标,对蛋白酶解工艺条件进行优化,探讨蛋白酶解液的分子量分布与抗氧化活性的关系。结果表明:在碱性蛋白酶、pH8及酶解9h的条件下,蛋白酶解液有较高的DPPH·清除率和蛋白回收率;脱脂脱酚核桃粕酶解液DPPH·清除率83.29%高于谷蛋白酶解液79.25%和球蛋白酶解液72.27%,蛋白回收率分别为69.83%、66.42%和73.71%。脱脂脱酚粕、谷蛋白和球蛋白酶解液以小分子肽居多,其中相对分子量≤1000的肽段分别占总量的42.73%、63.91%和55.10%,推测其抗氧化活性可能与小分子肽含量有关。     

Influence of Hydrolysis Degree on the Functional Properties of Salmon Byproducts Hydrolysates

ABSTRACT: Protein hydrolysates from salmon heads were obtained by enzymatic treatment with Alcalase^(r) 2.4L. Response surface methodology (RSM) allowed optimization of temperature, enzyme/substrate, and pH leading to various hydrolysates (11.5% to 17.3% hydrolysis degree [DH]) and protein recovery ranging from 47% to 70%. Size exclusion chromatography of hydrolysates showed that small peptides increased only at high DH. The nitrogen solubility index (NSI) of hydrolysates was higher than 75% over a wide range of pH values, whereas hydrolysates with high DH had the best solubility. Emulsifying capacity, emulsion stability, and fat absorption capacity were better when DH was low.     

水相酶解法提油工艺对菜籽蛋白功能特性的影响

采用纤维素酶、果胶酶、Alcalase蛋白酶对油菜籽进行水相酶解法制取油脂和蛋白。对传统水剂法制油及水相酶解法提油工艺所得菜籽蛋白的功能特性进行了对比研究。研究表明：在实验条件下，工艺过程对菜籽蛋白的功能特性有一定的影响，表现为低度改性，所得菜籽蛋白溶解度显著提高，尤其是在菜籽蛋白等电区域。同时具有更好的起泡性、乳化性、持水性、吸油性，但泡沫稳定性和黏度比传统水剂法有所降低。这些功能特性的变化使之更有利于用做食品原料。     

Proteolytic processing of herring (Clupea harengus): biochemical and nutritional characterisation of hydrolysates

Food research on fish has demonstrated that they constitute excellent nutritional components. The aim of the present work, was to process herring ( Clupea harengus ) using Protamex^® and evaluate the distribution of nutrients in various fractions obtained following membrane filtration. The fish starting material was composed of approximately 88% water and the dry matter contained 59% crude proteins, 33% lipids and 5% minerals. The recovery of fish dry matter in the liquid hydrolysate was 67.8%. Most protein enriched fractions demonstrate a well-balanced amino acid composition, notably the most essential amino acids. These protein fractions are characterised by biomolecules having a relatively low molecular weight (45 kDa and less) range. Even though the process could be optimised, the biochemical and nutritional analyses indicate that the herring may serve as high-value products for future applications in the health and food sectors.