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211.
秘鲁外海茎柔鱼产量分布及其与表温关系的初步研究   总被引:16,自引:3,他引:16  
根据2004年1-12月我国鱿钓船在东南太平洋海域茎柔鱼的生产统计和表温数据,按经纬度1°×1°的格式利用Marine Exlporer4.0软件,对其各月产量、平均日产量的分布以及与表温的关系进行分析。结果表明,1-7月产量主要集中在14°~17°S、80°~84°W海域,8-9月在9°~11°S、81°~83°W海域,12月在14°S以南海域。由此判断,作业渔场随月份进行西北-东南方向移动。全年都有较高的平均日产量,主渔汛为5-12月。作业渔场的适宜表温为18~22℃、24~25℃,其结果经过K-S检验。但适宜表温随季节发生变化。  相似文献   
212.
Cadmium (Cd) is a toxic environmental pollutant with a long biological half-life and can produce both hepatic and renal injuries in mammals and fish. Squid viscera meal (SVM), an effective attractant for aquatic animals, is widely used as an ingredient in aquafeeds. However, SVM is rich in Cd and its complexes. A study was conducted to evaluate the effects of dietary SVM on the growth and Cd deposition in the tissues of large yellow croaker, Pseudosciaena crocea R. Three practical diets were formulated to contain a 0, 50 and 100 g · kg−1 SVM diet, correspondingly containing a 0.21, 7.26 and 12.08 mg Cd · kg−1 diet. Each diet was randomly assigned to triplicate groups of 100 juveniles of large yellow croaker (mean initial weight, 9.75 ± 0.35 g) in floating sea cages (1.0 m × 1.0 m × 1.5 m). Fish were fed twice daily (05:00 and 17:00) to satiation for 8 weeks. The results showed that there were no significant differences in fish survival among the three dietary treatments, but significant higher specific growth rates (SGR) were observed in the fish fed diets with 50 or 100 g · kg−1 SVM diet compared to the control group (P < 0.05). The cadmium concentrations in fish tissues (muscle, liver, kidney and gill) were significantly influenced by the dietary SVM. The cadmium concentrations in all tissues significantly increased with increasing dietary Cd levels (P < 0.05). In all the dietary treatments, the highest Cd level was always observed in the kidney, followed by the liver and the gill. Fish fed diets with 50 and 100 g · kg−1 SVM had significantly higher Cd accumulations in the kidney (2.65, 4.44 mg · kg−1), liver (0.58, 0.93 mg · kg−1) and gill (0.35, 0.53 mg · kg−1) compared with the control group (0.42, 0.26 and 0.12 mg · kg−1, respectively). The Cd level in fish muscle, however, was undetectable in all treatments. Therefore, based on these results, accumulation of Cd in edible tissue (muscle) of farmed large yellow croaker is not a food safety issue. However, long-term feeding of diets with SVM may result in accumulation of Cd in the kidney, liver and gills of fish.  相似文献   
213.
The Patagonian longfin squid Loligo gahi undertakes horizontal ontogenetic migrations on the Falkland shelf: juveniles move from spawning grounds located in shallow, inshore waters (20–50 m depths) to feeding grounds near the shelf edge (200–350 m depths). Immature squid feed and grow in these offshore feeding grounds and, upon maturation, migrate back to inshore waters to spawn. The possible influence of environmental factors on L. gahi migrations was investigated using data from oceanographic transects, crossing the region of known L. gahi occurrence. They were made from the inshore waters of East Falkland eastwards to depths of 1250 m on a monthly basis from 1999 to 2001. Four main water types were found in the region: Shelf, Sub‐Antarctic Superficial and Antarctic Intermediate water masses, and Transient Zone waters. The inshore spawning grounds occur in the Shelf Water mass, whereas the feeding squid (medium‐sized immature and maturing individuals) were associated with the Transient Zone. The 5.5°C isotherm appeared to mark the limit of squid distribution into deeper waters in all seasons. Seasonal changes in water mass characteristics and location were found to be important for seasonal changes in L. gahi migrations on the Falkland shelf.  相似文献   
214.
鱿鱼肝油微胶囊化技术研究   总被引:3,自引:0,他引:3  
试验采用鱿鱼肝油为芯材,辛烯基琥珀酸淀粉酯为主要壁材,以壁材比例、乳液浓度、油脂添加量、喷雾进风温度等为单因素进行微胶囊化工艺研究,并利用响应面分析法对鱿鱼肝油微胶囊化工艺进行优化。结果表明,以微胶囊包埋率为响应值,壁材比例、乳液浓度及进风温度为响应因子,建立回归模型,该模型能够较好预测鱿鱼肝油微胶囊化效果;并得到最优工艺参数为:壁材比例(HI-CAP100∶环糊精)92∶23,乳液浓度21%,喷雾进风温度171℃,微胶囊包埋率为94.09%。  相似文献   
215.
Squid ink, a by-product from the squid production process, has been demonstrated to be a multifunctional marine bioactive material that can promote freshness of shiokara and peeled shrimp. However, the preservative effect it has on marine fish as well as its preservative mechanisms are still unknown. In this article, Sparus latus was used as a model to assess the preservative effects and the possible mechanism of the ink through chemical parameters, antibacterial effect, and sensory analysis. Melanin-free extract from squid ink at a concentration of 45 mg/mL and pH 8.5 was revealed to be effective in prolonging cold storage shelf life of Sparus latus, which was confirmed through comprehensive sensory analysis evaluation and measurement of chemical changes including pH, microbial count, total volatile basic nitrogen (TVB-N) value, and nucleotide analysis. It was also discovered that the extract mainly suppressed putrefying bacteria separated from Sparus latus, and the bacteriostatic range was confirmed to be wide. Squid ink significantly prolonged the cold storage period of Sparus latus, indicating that it may be developed to be a natural preservative for marine products.  相似文献   
216.
闽南—台湾浅滩渔场中国枪乌贼生物学特性研究   总被引:3,自引:0,他引:3  
本文根据1995年和2006~2007年测定中国枪乌贼生物学资料,进一步对闽南--台湾浅滩渔场中国枪乌贼生物学特性作比较系统分析研究,结果表明:闽南--台湾浅滩渔场中国枪乌贼产卵时间为4~9月,高峰期为5月和8月.春季产卵群体个体较大,大部分为180~200mm,7月份当年春生的幼体开始加入捕捞群体,7~9月群体个体大小参差不齐,既有秋季产卵群体又有索饵幼体,10~12月以索饵群体为主(胴长优势组100~120mm).中国枪乌贼胴长(L)与体重(W)的关系:W=1.7246×103L2.2754R2=(R20.9845).摄食强度以1级为主占41.7%,2级占23.89%,食性凶猛、营养级为2.62.生殖群不甚摄食,空胃率高.与历史资料同比,单拖作业生产汛期6~9月渔获群体平均胴长由上世纪70年代的211.7mm下降至90年代的150.3mm、光诱敷网作业生产汛期渔获群体从2000年的157.2mm下降到2006~2007年的144.8mm.目前雌性性成熟最小胴长103mm也比以往小,性早熟现象明显.为此,建议对中国枪乌贼的资源应加以合理利用和保护.  相似文献   
217.
To elucidate the effects of hydrographic conditions on the migration and distribution of diamond squid ( Thysanoteuthis rhombus ) in the Sea of Japan, two numerical experiments were conducted using a Lagrangian particle-tracking model. First, Lagrangian simulations with different horizontal swimming speeds were conducted in the area off the San-in coast, the southwest Sea of Japan. The comparison results of simulations and experimental tagging records from 2003 suggest that horizontal movement of diamond squid over a few days is influenced by individual swimming, but long-term migration over more than about 10 days is dependent on the ambient current field. Secondly, further Lagrangian simulations with biological processes, forced by different hydrographic conditions in 2003–2005, were conducted. Temporal variations in distributions and sizes calculated by the model corresponded approximately to those of catch data. A large number of particles simulating squid were distributed over the nearshore region from the San-in coast to the Noto Peninsula during September–November every year. Differences in the migration route and distribution of particles among years were closely related to differences in hydrographic conditions such as the position of the main stream of the Tsushima Warm Current. Prediction of the catch off the San-in coast might be improved by considering hydrographic conditions in the southwest Sea of Japan.  相似文献   
218.
营养彩椒鱿鱼肠的研制   总被引:1,自引:0,他引:1  
以鱼糜和鱿鱼肉块生产鱼肉肠,在保持鱼肉肠原有风味的同时,赋有鱿鱼的肉感和特殊咬感,并添加彩椒,提高产品的感官品质。彩椒鱿鱼肠的最佳配方为:鱼糜与鱿鱼肉块的质量比为6:4;彩椒添加量10%,淀粉5%,蛋清5%,食盐3%。  相似文献   
219.
为了改善鱿鱼与白鲢鱼混合鱼糜制品的凝胶特性,本研究通过鱼糜制品的感官评价、凝胶强度、持水性、白度、水分分布、肌原纤维蛋白凝胶电泳和光学显微镜观察等指标,分析鱿鱼与白鲢鱼混合比例对鱼糜制品凝胶特性的影响。结果表明,当鱿鱼与白鲢鱼混合比例为3∶4时,凝胶特性最好,其中鱼糜凝胶的凝胶强度及持水性较混合比例为5∶2时分别提高了42.74%和2.93个百分点;感官评价总分、白度值显著高于其他混合比例(P<0.05),分别为76.3和72.3,不易流动水相对含量显著高于其他混合比例(P<0.05),且该比例下鱼糜凝胶网络结构致密均一,对水分的束缚能力强。肌原纤维蛋白电泳结果显示,混合比例为3∶4时,肌球蛋白重链交联程度高,形成了大分子聚集体。综上,当鱿鱼与白鲢鱼混合比例为3∶4时,可明显改善混合鱼糜制品的凝胶品质。本研究结果为提高鱿鱼鱼糜制品的凝胶品质及生产研发提供了一定的理论依据。  相似文献   
220.
为探究脱色工艺及其对鱿鱼皮胶原蛋白肽风味的影响,本试验在酶解制备的基础上,研究了不同活性炭和树脂对鱿鱼皮酶解液的脱色效果及最优工艺,并采用电子舌、电子鼻、氨基酸分析及感官评价等方法对鱿鱼皮胶原蛋白肽风味变化进行了分析。结果表明,粉末状活性炭的脱色效果较好,最佳脱色工艺为:pH值2.0,添加量0.1%(m/v),30℃下脱色30 min,该条件下鱿鱼皮酶解液的脱色率和蛋白损失率分别为82.91%和24.81%。分子量分布与游离氨基酸分析结果表明,与脱色前相比,脱色后样品的分子量分布变化不大,游离氨基酸及苦味氨基酸含量下降,鲜味氨基酸占比上升。电子舌、电子鼻及感官评价结果表明,脱色前后样品的风味差异较大,脱色后,样品的风味有显著改善,表现为苦味下降,鲜、酸、咸味提升。本研究结果为鱿鱼皮高附加值产品的开发及胶原蛋白肽的应用提供了一定的理论依据。  相似文献   
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