Energy use in controlled temperature marine aquaculture

Temperature control offers benefits in land‐based marine aquaculture: stock growth rates may be enhanced by heating in winter; mortality rates in summer may be reduced by cooling. However, if the plant is not well designed, temperature control may create very large energy demands. This paper describes the application of temperature control in abalone aquaculture in New Zealand, with a focus on energy considerations in plant design. An abalone farm using a semi‐closed water conditioning system is used as a case study for which an energy model, based on a heat pump system, is developed. The model is used to determine the impact of plant design and tank conditions on the economics of the operation. Copyright © 2002 John Wiley & Sons, Ltd.     

Algal phagostimulants for marine herbivorous gastropods

Methanol extracts of the green algaUlva pertusa contain four kinds of glycerolipids that are active as feeding-stimulants for marine herbivorous gastropods. These compounds are digalactosyldiacylglycerol (DGDG), 1,2-diacylglycerly-4-O-(N,N,N-trimethyl)-homoserine (DGTH), 1-monoacylglyceryl-4'-O-(N,N,N-trimethyl)-homoserine (MGTH), and 6-sulfoquinovosyldiacylglycerol (SQDG). The various gastropods exhibit marked specificity, however, as young abaloneHaliotis discus respond to DGDG and DGTH at minute dosages of 20–30 g/sample zone, but do not respond to 300 g of SQDG, which is a phagostimulant for two other kinds of gastropods,Turbo comutus andOmphalius pfeifferi.Chemical Studies on Phagostimulants for Marine Gastropods. Part VI. For Part V, see Sakata et al. (1986b).     

Feeding-stimulant activity of algal glycerolipids for marine herbivorous gastropods

Phagostimulant activity of glycerolipids such as digalactosyldiacylglycerol (DGDG), 6-sulfoquinovosyldiacylglycerol (SQDG), phosphatidylcholine (PC), phosphatidylethanolamine (PE), etc., have been examined using the Avicel plate method for three kinds of marine herbivorous gastropods, the abaloneHaliotis discus, the turban shellTurbo cornutus, and the topshellOmphalius pfeifferi. DGDG showed strong activity for all the test animals. SQDG was much less active than the other glycerolipids for abalone. The turban shell and the top shell responded more or less sensitively to all tested glycerolipids at doses of 10–20g/sample zone.Chemical Studies on Phagostimulants for Marine Gastropods. Part VIII. For Part VII, see Sakata et al. (1988a).     

酶法制备鲍鱼脏器呈味肽及呈味氨基酸

研究了酶法制备鲍鱼脏器呈味肽及呈味氨基酸的最佳条件.鲍鱼脏器分别经中性蛋白酶、木瓜蛋白酶和胰蛋白酶水解,中性蛋白酶酶解产物的水解度和肽得率最大,鲜味氨基酸含量最高且口味最好.以中性蛋白酶为工具酶,通过单因素试验和响应面分析确定了酶解的最佳条件:酶加量3 000 U/g,温度46℃,pH 7.8,时间3 h,底物质量分数...     

美拉德反应制备鲍鱼脏器肽呈味基料及其抗氧化活性研究

采用美拉德反应处理皱纹盘鲍脏器肽制备呈味基料,并通过感官评定实验及体外抗氧化实验评价了美拉德反应处理对鲍鱼脏器肽风味及抗氧化活性的影响.结果表明,鲍鱼脏器肽经美拉德反应处理后,鲜味增加,腥、苦等不良口味下降,总体风味得到显著提升.与反应前相比,美拉德反应产物的DPPH自由基清除活性增强百倍,而羟自由基清除活性及还原活性...     

超滤膜分离鲍鱼内脏酶解物及其体外抗氧化活性的研究

利用超滤膜对鲍鱼内脏酶解物进行分离,考察了各分子量段酶解物的成分组成和抗氧化活性。利用截留分子量为10000 u、3000 u、500 u的超滤膜分离得到FA、FB、FC和FD等四个组分中,FA组分的总糖和蛋白含量分别为34.06%和17.20%,而FB、FC和FD等组分主要是由蛋白组成,其游离氨基酸含量分别高达23.20、25.4、28.68 g/100g。根据Tricine-SDS-PAGE和β-消除反应的分析结果,表明FA中位于间隔胶的高分子组分(HMWF)含有N-糖苷键结合的糖蛋白,而分子量为25 ku的成分主要是蛋白。凝胶渗透色谱数据表明FB、FC和FD的分子量主要分布在300 u左右。另一方面,体外抗氧化结果表明,在低浓度下FA组分具有较强的DPPH自由基清除活性和还原力;当质量浓度高于5 mg/m L时,各超滤组分的DPPH自由基清除活性无明显差异,但FB、FC和FD组分的还原力明显高于FA组分;不管是低浓度还是高浓度,FB、FC和FD组分的羟自由基清除活性都明显高于FA组分。     

鲍内脏酶解工艺条件的优化

目的建立鲍内脏酶解工艺条件,为鲍内脏多糖、多肽的工业化生产提供参考。方法以多糖提取率和蛋白质水解度为指标,研究p H值、提取温度、料液比、加酶量和酶解时间等因素对鲍内脏酶解效果的影响,运用响应面设计优化酶解工艺参数。结果选用木瓜蛋白酶与胰蛋白酶对鲍内脏进行复合酶解,适宜的酶解条件为p H 8.0、酶解温度40℃、料液比1:40,加酶量3000 U/g,在此条件下,比较不同酶解时间对酶解产物的影响,发现多糖提取率在酶解6 h时达到最大,为16.58%,而酶解液的水溶性蛋白含量、蛋白质水解度和对DPPH清除率均随酶解时间的延长而增加。结论木瓜蛋白酶与胰蛋白酶复合酶解鲍内脏效果良好,能够获得较高的多糖提取率,酶解液具有良好的清除DPPH活性。     

Abalone (Hariltis discus): Seasonal Variations in Chemical Composition and Textural Properties

Seasonal changes in adenosine 5′-triphosphate, total free amino acids, and total oligopeptides in abalone meat were analyzed. Levels were higher in summer and lower in winter. In both seasons, the most abundant free amino acid was taurine followed by arginine, glycine, glutamine, and glutamic acid. The largest peptide-bond amino acid was glutamic acid + glutamine. The collagen content decreased in summer and increased in winter. The breaking stress values of the meat were low in summer and high in winter, indicating that summer abalone would be more tender. Scanning electron microscopy revealed the collagen network was more compact in winter.     

鲍鱼及其副产物综合加工利用研究进展

鲍鱼作为海珍品深受国内外广大消费者的喜爱。随着养殖技术的日益成熟和养殖产量的不断增长,中国已成为世界第一鲍鱼养殖和消费国家。为提高鲍鱼产品原料利用率和产品附加值,鲍鱼加工技术也逐渐向综合利用和高新技术方向发展。本文综述鲍鱼肉的加工利用现状（干鲍、冻鲍、鲍鱼罐头）,并对其加工工艺进行具体介绍;同时综述鲍鱼加工下脚料（内脏）及鲍鱼壳的高值化开发利用现状,并对鲍鱼综合加工与利用前景进行展望,旨在为鲍鱼的进一步开发利用提供参考。