共查询到19条相似文献，搜索用时 867 毫秒
1.
研究鲜活和不同加热时间条件下沙蛰组织构造及流变学特性的变化。组织构造变化采用Van Gieson染色法观察和扫描电镜观察,流变学特性参数通过应力松弛和破断实验进行测定。结果表明,沙蛰样品在加热过程中其重量和体积均呈现显著减小趋势;流变学特征参数弹性模量E0和破断强度逐渐减少,而松弛时间τ1、粘性模量η1却呈现明显增加趋势,而且流变学特征参数与组织结构变化之间具有较好的相关性。这些变化主要是由于加热过程中沙蛰样品的蛋白质发生热变性所引起。与鲜活样品相比,加热样品具有弹性较大、粘结性较大和硬度小的特点。 相似文献
2.
研究牙鲆在冰温贮藏条件下鱼肉的鲜度指标(pH值、K值、TVB-N、细菌总数)和质构特征参数(感官评定、组织构造、破断强度等)的变化,并与冷藏样品的相应变化进行了比较分析.结果表明,随着贮藏时间的延长,菌落总数、K值和TVB-N上升,pH值则先下降后上升,冷藏后期样品pH值上升较快且很高;至货架期终点时破断强度呈减小趋势,组织结构逐渐劣化.与冷藏样品相比,冰温贮藏条件能更有效地抑制牙鲆鱼体内微生物的作用,延长牙鲆的贮藏期. 相似文献
3.
研究冻结贮藏条件下鲈鱼组织构造、质地剖面分析（TPA）及流变学特征参数（弹性模量E,应力松弛时间τ,粘性模量η,破断强度gf）的变化,同时结合鲜度指标（细菌总数,K值,TVB—N,pH值）和感官特性判断其品质变化特征。结果表明：随着冻结时间的延长,鲈样品细菌总数下降,K值和TVB—N上升;组织构造呈现纤维间空隙增大、方向性增强、断裂崩解的趋势;弹性模量呈上升趋势,破断强度、硬度、弹性、粘聚性、咀嚼性均呈下降趋势,应力松弛时间、粘性模量的变化则不显著。与冷藏样品相比,冻结样品具有鲜度高、货架期长的特点。 相似文献
4.
微冻贮藏条件下鲈鲜度和质构变化 总被引：5，自引：0，他引：5
研究鲈在微冻贮藏条件下组织构造、质地剖面分析(TPA)及流变学特征参数(弹性模量E,应力松弛时间τ,粘性模量η,破断强度)的变化,同时结合鲜度指标、细菌总数、K值、TVB-N、pH值和感官特性判断其在微冻条件下的品质变化特征。结果表明,随着贮藏时间的延长,菌落总数、K值和TVB-N上升,pH值则先下降后上升,且上升速度随温度的升高而加快;组织结构呈现肌原纤维间空隙逐渐增大,方向性增强,构造逐渐断裂崩解的趋势;弹性模量呈上升趋势,破断强度、硬度、弹性、粘聚性、咀嚼性呈下降趋势,而应力松弛时间、粘性模量的变化则不显著。与冷藏样品相比,微冻样品的货架期能够延长20 d,说明微冻条件比冷藏条件能更有效的抑制鲈体内酶活性及微生物的作用,缓解蛋白质分解,延长鲈的贮藏期。 相似文献
5.
不同加热条件下海螺足部质构的变化 总被引：1，自引：0，他引：1
研究了鲜活和不同加热条件下(5、20、60 min)海螺足部的组织构造及其流变学特性的变化,并进行了质地剖面分析(TPA)和感官评定试验,为海螺深加工制品的开发及加工工艺的优化提供理论基础和科学依据.组织构造变化采用Van Gieson染色法观察,流变学特性参数和TPA通过质构仪测定,同时比较了TPA和感官评定间的相关性.结果表明:不同的加热处理对海螺足部的组织结构和流变学特征参数有明显影响.流变学特性与组织结构的变化之间具有一定的关联性.流变学特征参数表明鲜活海螺足部的肌肉具有硬度大、弹力和粘着性小的质地特点,而加热样品则是硬度小、弹力和粘着性大.海螺足部的热加工应以加热20 min为宜,时间太短或过长都无法给人以最佳的口感.TPA和感官评定在硬度(R=0.969 2)、弹性(R=0.927 2)和咀嚼性(R=0.854 2)方面呈显著相关性,在粘着性(R:0.794 5)方面也有较好的相关性. 相似文献
6.
为研究鲜活和不同加热温度下刺参体壁组织构造及其胶原纤维结构的变化,采用VanGieson染色法观察组织构造、采用细胞分裂扫描电镜法(cell-maceration/SEM)观察胶原纤维结构,同时利用示差扫描量热仪(DSC)测定刺参肌肉蛋白质的热收缩温度。结果发现,在不同加热温度条件下,刺参体壁组织构造及其胶原纤维结构均发生显著变化。随着加热温度的升高,刺参肌肉组织中纤维逐渐聚集交联,形成多孔网状结构;蛋白质发生热变性、胶原纤维结构收缩,导致纤维排列紧密,纤维间孔隙度呈减小趋势。与刺参整体组织构造的变化相比,胶原纤维结构的变化尤其明显。鲜活刺参体壁肌肉蛋白质的热收缩温度为68.92℃,加热过程中蛋白质的热变性是引起其构造变化的主要原因。 相似文献
7.
运输对养殖黄颡鱼血液生化和肌肉物性分析指标的影响 总被引：1，自引：0，他引：1
测定了在10.4~11.2℃下运输4 h后不同时间(0 h、1 h、3 h、6 h、12 h、1 d、3 d、7 d和20 d)养殖黄颡鱼(Pelteobagrus fulvidraco)血液生理生化指标和肌肉物性分析指标的变化。结果显示,运输引起了黄颡鱼血清皮质醇和血糖浓度的显著升高(P0.05),在运输结束12 h后恢复到正常水平。运输后鱼体血清超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和总抗氧化能力(T-AOC)均有显著性升高,随着恢复时间的推移逐渐回降到正常水平;但过氧化物酶(POD)活性并未出现显著性差异,维持稳定的水平。运输后肌肉硬度、弹性、胶黏性、凝聚性、咀嚼性、回复性等物性分析指标均显著性降低。除了凝聚性和咀嚼性之外,其他肌肉物性分析指标在运输结束72 h后恢复到正常水平。研究表明,长途运输造成了养殖黄颡鱼的应激反应,对肌肉物性特征产生了显著的影响,但运输后的恢复可使鱼体抗氧化能力和肌肉物性分析指标回复到正常水平。 相似文献
8.
鲢、狭鳕鱼糜微波加热凝胶形成的动力学分析 总被引：3，自引：0，他引：3
以鲢（Hypophthalmichthys mollitrix）和狭鳕（Theragra chalcogramma）鱼糜为对象,在微波、水浴两种加热条件下,对鱼糜及鱼糜大豆蛋白复合素材试样的凝胶特性——破断力值加以测定,进而考察不同加热方式下两种鱼糜的凝胶形成速度以及微波加热所需的活化能,并对试样能量吸收值进行了比较。结果表明：（1）鲢、狭鳕鱼糜微波加热凝胶形成速度比传统水浴加热高两个数量级,不同鱼种的鱼麋微波加热凝胶形成速度有一定的差异性（P〉0．05）。（2）微波加热下,欲达到相同的破断力值,鲢需要高于狭鳕1倍的活化能,两者对应的复合素材的活化能均小于相应的单一鱼糜试样。（3）与水浴加热相比,在能量吸收值相同的情况下,微波加热试样能达到更高凝胶破断力值。 相似文献
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10.
研究了鲜活和不同加热条件下（5、20、60min）海螺足部的组织构造及其流变学特性的变化,并进行了质地剖面分析（TPA）和感官评定试验,为海螺深加工制品的开发及加工工艺的优化提供理论基础和科学依据。组织构造变化采用Van Gieson染色法观察,流变学特性参数和TPA通过质构仪测定,同时比较了TPA和感官评定间的相关性。结果表明：不同的加热处理对海螺足部的组织结构和流变学特征参数有明显影响。流变学特性与组织结构的变化之间具有一定的关联性。流变学特征参数表明鲜活海螺足部的肌肉具有硬度大、弹力和粘着性小的质地特点,而加热样品则是硬度小、弹力和粘着性大。海螺足部的热加工应以加热20分钟为宜, 时间太短或过长都无法给人以最佳的口感。TPA和感官评定在硬度（R=0.9692）、弹性（R=0.9272）和咀嚼性（R=0.8542）方面呈显著相关性,在粘着性（R=0.7945）方面也有较好的相关性。 相似文献
11.
ABSTRACT: Changes in tissue structures, rheological properties, and water content of abalone meat were studied in relation to boiling and steaming time. The adductor muscle of abalone Haliotis discus, which was removed directly from the shell, was boiled or steamed for 1 h, 2 h, and 3 h. When observed under a light microscope and by scanning electron microscopy, structural changes in the myofibrils were greatest in the boiled abalone meat compared with the steamed meat. When heating time was increased from 1 h to 3 h, the instantaneous modulus E 0 of boiled abalone meat decreased gradually with increased heating time, whereas the E 0 of steamed abalone meat was reduced when heated for 2 h. When heated for 1 h, the relaxation time of steamed abalone meat was much longer than that of boiled meat. There were no significant changes in the relaxation time of abalone meat among the different boiling times, but the relaxation time of steamed abalone meat was reduced gradually with increasing heating times. The study's results confirmed that the difference in rheological properties between the boiled and steamed meats was due mainly to the denaturation level of myofibrils when heated for 1 h, as well as due to the changes in water and solid content and the manner in which the inner water was exchanged after heating time was increased from 1 h to 3 h. 相似文献
12.
Zhaohui Zhang Qian Liu Pei Wang Fan Liu 《Journal Of Aquatic Food Product Technology》2017,26(2):205-214
Changes in tissue structure and rheological properties of abalone meat with cold air drying and natural drying were studied. Natural drying took 168 h, while cold air drying took 120 h, which was 71% of natural drying. Nutrition loss of cold air drying abalone meat was less than that of natural drying samples. Muscle fibers in heated samples reassembled, and voids in muscular tissue extended. With drying time increasing, muscle fibers in abalone meat shrank, and the size of aperture among myofibrils decreased. While drying finished, myofibrils in cold air drying abalone meat had a homogeneous network structure, which was fit for water restoration. Rheological properties (elasticity modulus E, viscosity modulus η, and rupture strength) in heated samples were smaller than those in raw samples, while the relaxation time τ was greater. During the drying process, E, η, and rupture strength tended to increase, and the relaxation time τ had no significant regularity changes. Compared with natural drying, the cold air drying had more advantages in actual production as the drying time was shorter, and the drying process and sanitary conditions were easy to control. 相似文献
13.
Fisheries managers and scientists worldwide are struggling with a lack of basic information for many shark and ray species. One factor hampering the data collection is inaccurate identification of many chondrichthyan species and their body parts. Morphologically similar species, and specimens which are poorly preserved or have had key diagnostic features removed, can be difficult to identify. This study examined DNA barcoding as a method to identify shark species from dried fins, confiscated from a vessel fishing illegally in Australian waters. 211 left pectoral fins were examined. 18 either did not provide a sequenceable product or yielded a microbial sequence, while 193 fins (91.5%) provided a chondrichthyan sequence. All of these could be matched to reference specimens in a DNA barcode database, and so were able to be identified. 27 species were detected, 20 species of sharks and seven species of rays The most abundant species (22% of fins) was Carcharhinus dussumieri. Many of these species are listed on the World Conservation Union (IUCN) Red List and include one, Anoyxpristis cuspidata (3%), rated as critically endangered. Fishing authorities can use DNA barcoding to gather data on which chondrichthyan species are targeted by illegal fishers, information that will greatly assist in management and conservation. 相似文献
14.
鱼皮明胶蛋白膜的制备及其热稳定性 总被引：5，自引：0，他引：5
利用鲨鱼皮明胶制备蛋白可食膜,测定了成膜液蛋白浓度、甘油含量对明胶蛋白膜理化性质的影响,以及环境湿度对膜热稳定性的影响.结果发现,利用鲨鱼皮明胶可以制备成无色透明的蛋白可食膜,成膜液蛋白浓度对明胶蛋白膜的断裂延伸率(EAB)、水蒸气透过率(WVP)以及透明度值有一定的影响,对拉伸强度(TS)没有发生显著影响,但甘油含量从10％增加到70％时蛋白膜的TS逐渐降低.利用DSC对膜的热稳定性进行分析,结果表明当水分活度(Aw) ＜0.33时,明胶蛋白膜在常温下可以处于玻璃态,机械性质能够保持稳定.然而,当Aw超过0.44后,膜的玻璃化转变温度(Tg)起始点低于25℃,膜的EAB上升,TS出现显著下降.当Aw达到0.92时,膜甚至开始溶解变成溶胶.因此,利用鲨鱼皮制备的明胶蛋白膜只适合在Aw小于0.44的干燥环境中应用. 相似文献
15.
《Journal Of Aquatic Food Product Technology》2013,22(3):53-67
Abstract Gel was prepared from shark myofibrillar proteins by reducing the pH of washed, collagen-free, shark meat homogenate in water to 4.0 by acetic acid. The gel was homogenized in water at a protein concentration of 3% (w/v) to get low viscous (free-flowing) dispersion. Proteins in the dispersion were stable to heating at 100°C. However, the proteins were precipitated when the dispersion was heated after either increase of pH to 6.0 or addition of salts. Spray drying of die dispersion gave colorless and odorless protein powder. Some characteristics of the powder are discussed. 相似文献
16.
Md Robiul Hasan Jennifer A. Chaplin Peter B. Spencer Matias Braccini 《Fish and Fisheries》2023,24(5):777-795
Sharks and rays evolved 450 million years ago, during the Late Ordovician Period. However, during the modern Anthropocene, shark populations have declined at considerable rates, and recent global assessments indicate about one in three species is threatened with extinction. A notable reason for this elevated extinction risk is overfishing linked to increased demand for shark fins and other products. Here, we review multiple dimensions of consuming shark products, ranging from stock sustainability, product (mis)labelling and trade, the human health implications of consuming shark products, and illegal, unreported and unregulated fishing and slavery and labour abuses in the fishing industry. We conclude that traceability and increased transparency in seafood supply chains is essential to overcome obstacles to consumption of sustainable, ethical and healthy shark products. We also provide a decision tree outlining steps in consumer choice that would foster such consumption. Our aim is to provide a holistic view on issues concerning the consumption of shark products that will help policymakers, the public, management and law enforcement agencies to advocate for ecologically- and ethically sustainable consumption of shark products and thereby empower the general public to make informed decisions on which shark products they consume. 相似文献
17.
Helena M. Moreno Carlos Cardoso M. Teresa Solas 《Journal Of Aquatic Food Product Technology》2013,22(4):312-330
Depending on the season of capture, giant squid (Dosidicus gigas) surimi processed by isoelectric precipitation presents low gel strength. Addition of microbial transglutaminase (MTGase) and application of high isostatic pressure (300 MPa) to improve physicochemical properties were assayed for purposes of making “suwari” gels and heated gels for use in restructured products which have a raw or cooked appearance. The physicochemical properties of both pressurized and unpressurized gels induced by application of 30°C/1 h improved when MTGase was added. In contrast, addition of MTGase was less effective in gels subsequently heated at 90°C/30 min after 30°C/1 h. High pressure treatment for 30 min at 300 MPa and 15°C helped to produce gels with better mechanical and water binding properties, whether treated for 30°C/1 h only or for 30°C/1 h plus 30-min heat treatment at 90°C. High pressure treatment also reduced lightness. 相似文献
18.
Johann Mourier Marc Soria Antonin Blaison Monique Simier Grégoire Certain Angélique Demichelis Tarek Hattab 《水产资源保护:海洋与淡水生态系统》2021,31(10):2926-2937
- Knowledge about spatial and temporal variability in the distribution and abundance of predators is necessary to adapt measures to mitigate human–wildlife interactions.
- Acoustic telemetry and network analyses were used to investigate the spatial ecology of bull sharks, the species responsible for most shark bites in Reunion Island, one of the world's shark bite hotspots.
- The west coast of the island was not used uniformly by every individual, with size predicting the movements of sharks along the coast.
- Node-based metrics – closeness, node strength, and cumulated continuous residency times – derived from up to 181 monthly movement networks from 20 individuals, revealed that smaller sharks (<250 cm total length) primarily used the south-west coast while larger individuals spent most of their time in the northern region with regular visits to multiple areas along the coast.
- This study provides essential knowledge on bull shark behaviour and central areas used at different periods of the year, which correlates well with the dynamics of observed shark bites. Our approach provides a non-invasive alternative to help predicting and anticipating human–shark conflicts and avoid shark culling programmes detrimental to the conservation of large predators such as sharks.
19.
ABSTRACT: In order to simplify the food chain in a closed ecological recirculating aquaculture system, raw Spirulina platensis cultivated in 50-L photobioreactors were fed to tilapia Oreochromis niloticus as a uni-feed from the onset of exogenous feeding. The feasibility of using tilapia grown on raw Spirulina (body weight: 155.4 ± 3.9 g, standard length: 16.2 ± 0.2 cm; n = 3) was investigated for 30 weeks for sashimi (sliced raw meat). Some of the rheological properties of the flesh were measured to clarify the obtained results of sensory evaluations of texture and fatness. The elastic modulus of flesh of the Spirulina -fed fish was significantly higher than that of the control fish (body weight: 168.9 ± 5.8 g, standard length: 17.8 ± 0.5 cm; n = 3) that were fed commercial diets. In addition, the viscosity of the flesh of the Spirulina -fed fish was significantly lower than that of the control fish. There was no significant difference in the rupture strength between the two treatments. The rheological parameters in the muscle were found to coincide with the results of the sensory assessment. These results suggest that tilapia fed solely on raw Spirulina have a high flesh quality that is suitable for sashimi. The muscle lipid of the raw Spirulina -fed fish had lower levels of non-polar lipids such as triglycerides and partial glycerides, but higher levels of polar lipids such as phosphatidylcholine and phosphatidylethanolamine. The fatty acid profile of the raw Spirulina -fed fish muscle, especially in the polar lipid fraction, was characterized by an abundance of Σn-6 highly unsaturated fatty acids (20:3n-6, 20:4n-6, 22:4n-6, 22:5n-6). 相似文献