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61.
[目的]为探究不同包装对丁香鱼干常温贮藏期间的品质特性影响,[方法] 以空气包装为对照,与真空包装、气调包装和CO2包装做比较,测定贮藏过程中菌落总数、TVB-N、POV、TBA、色差、挥发性风味成分及感官评分的变化。[结果]结果显示,真空、气调、CO2三种包装均能有效抑制丁香鱼干微生物生长,常温25 ℃贮藏8 d后,真空包装组样品TVB-N、POV和TBA值分别较空气包装组降低47.08%、4.13%和25.49%,并且真空包装组样品在减缓样品色泽变化、保护肌纤维结构完整性、保留挥发性风味成分和保持感官特性方面均具有较佳效果,确定了真空包装为丁香鱼干的最佳包装方式。基于Arhenius方程建立了丁香鱼干货架期预测模型,25 ℃和35 ℃下真空包装丁香鱼干的货架期分别为6.07和3.23 d。[意义]本研究成果可为丁香鱼干常温物流过程中的品质控制提供理论依据。  相似文献   
62.
Illex argentinus, the Argentine short-finned squid, is an important species within the Patagonian shelf ecosystem, where it supports a major multi-national fishery. The fishing fleet operating in this region is comprised of jigging vessels which attract squid using powerful incandescent lights. These fishing lights are detectable in remotely sensed satellite imagery which makes the fishery unusually amenable to a large-scale analysis of its spatial dynamics. In this paper, long-term inter-annual variability in fleet distribution and extent is examined using imagery from the Defence Meteorological Satellite Program-Operational Linescan System (DMSP-OLS) for the period 1993–2005. The fishery was found to occupy a wide area across the shelf and slope, with regions of consistent fishing activity observed on the high seas (45–47°S) and to the north of the Falkland Islands (Malvinas). Distribution of the fishery over the 13-year study period was variable, with 28% of the fished area occupied in 1–2 years, and 7% of the area occupied in 12–13 years. Annual catch levels were positively associated with the extent of the area occupied by the fleet. Higher catches corresponded to the fishery occupying a wide latitudinal range, whereas lower catches were observed during 2004 and 2005 corresponding to a contraction of the fishery away from the south of its range. In years of very high catches, fishing took place along almost the entire latitudinal range of the species. Due to the intensity of fishing, changes in the distribution of the fleet can reflect shifts in the distribution of I. argentinus; this has potential for the long-term monitoring of this highly variable squid fishery.  相似文献   
63.
用化学动力学法以过氧化值为表征参数预测几种贮存条件下炒制葵花籽货架期。以生葵花籽为原料,炒制后去壳,分别在4℃、25℃和40℃温度及10.5 k Pa和21.0 k Pa氧分压条件下贮存,测定贮存期间其过氧化值变化,进行动力学回归,求算化学反应动力学参数,进而结合感官评定预测炒制葵花籽的货架期。结果表明,葵花籽仁油脂氧化劣变呈一级化学反应特征,反应速率常数随温度的升高而增大,半衰期随温度的升高而下降,用过氧化值预测的货架期与感官评定结果接近。研究证明,用过氧化值法可预测炒制葵花籽的货架期,在低温、低氧分压贮存条件下可延长炒制葵花籽的货架期。  相似文献   
64.
分析了接合方式对板式家具搁板变形的影响,根据目前板式家具主要采用的搁板接合方式,选择了圆棒、金属销和偏心连接件等作为支撑与连接构件进行相应分析,从结构的刚性与搁板的承载能力方面来看,应优先选用可垂直拆装的偏心连接件.  相似文献   
65.
开架管理下图书分类及排架的思考   总被引:3,自引:1,他引:2  
根据本馆在开架管理下出现的新问题,分析了图书管理工作与图书排架号的关系,提出解决问题的几点意见。  相似文献   
66.
An experiment was conducted to investigate the effect of different initial pH on the storage characteristics and shelf life of liquid diet. 45 polypropylene bags were allotted to treatments 1, 2 and 3 on average, 100 g diet and 200 g water were placed into each polypropylene bag, food-grade DL-lactic acid was added to each bag at a rate of 0.0 mL in treatment l, 1.2 mL in treatment 2 and 4.7 mL in treatment 3, air was artificially expelled from each bag prior to heat-sealing. All bags were placed into a cage, cooked with steam at 90~C for 30 rain under normal pressure, then taken out and stored from day 0 to 60 at room temperature. Results indicated that liquid diet in treatment 3 achieved the highest total sensory scores, the pH value had a tendency to decrease and the bacteria count had a tendency to increase in the liquid diet with the advancing of storage time with the advancing of storage time, lowering the initial pH of liquid diet decreased the bacteria count, the AFBl and ZEN concentrations and increased the starch gelatinization degree from day 30 to 60, liquid diet in treatment 3 had a lower (P〈0.01) bacteria count and a higher (P〈0.05) starch gelatinization degree at day 30 and 45 than liquid diet in treatment 1. In conclusion, lowering the initial pH of liquid diet with lactic acid to pH 4 could effectively improve the storage characteristics and shelf life of liquid diet.  相似文献   
67.
台湾木本植物的大陆性特征   总被引:1,自引:0,他引:1  
对台湾木本植物科、属、种的大陆地理分布进行统计分析.结果表明,台湾有113科483属1675种木本植物,属的热带性质明显.全部科、462属均在我国大陆广泛分布,分别占台湾木本植物科、属的100%、95.65%,科、属级水平大陆性特征明显.台湾特有木本植物种类多(451种);台湾与大陆木本植物共有种有731种,占台湾木本植物的43.64%,多属于我国西南、华南、华东成分,西北、东北成分较少,种级水平大陆性特征不明显.台湾木本植物区系与我国大陆最为密切,其次为日本和菲律宾,同时与印度、马来西亚、朝鲜半岛也有联系.  相似文献   
68.
罗氏沼虾的气调保鲜   总被引:11,自引:0,他引:11  
研究不同配比的O2,CO2和N2的混合气体对罗氏沼虾的气调保鲜效果,采用涂布聚脂/聚丙烯(K-PET/PE)厚度为78μm的复合薄膜,用酯比为60%CO2/30%N2/10%O2及配比为75%CO2/20%N2/50%O2的两种不同的混合气体对罗氏沼虾进行气调保鲜包装,在6℃左右贮藏,通过与空气对照组的比较,发现混合气体可有效抑制微生物的生长并降低TVB-N的生成,而且含有高浓度CO2和低浓度O2的混合气体对微生物繁殖和TVB-N的抑制效果更好,实验结果表明:两种气调包装的罗氏沼虾经感官评定其一级鲜度可保持到第6天,二级鲜度和延续到第10天。  相似文献   
69.
水资源开发的水土环境效应评价是水资源可持续利用评价的前提和基础。根据干域的水土环境特点,分析了水资源开发的水土环境效应间的内在联系,论述了水土环境效应评价指标体系构建的必要性及其构建原则,设计了评价指标体系的大致框架,并就指标体系构建的合理性及指标设置方法进行了论证。  相似文献   
70.
Larval transport in the slope region off north‐eastern North America influences recruitment to juvenile habitats for a variety of fishes that inhabit the continental shelf. In this study, collections of larval fishes were made during springtime over the continental slope to provide insights into larval distributions and transport. Ichthyoplankton composition and distribution mirrored the physical complexity of the region. Three larval fish assemblages were defined, each with different water mass distributions. A Gulf Stream assemblage was found predominantly in the Gulf Stream and associated with filaments of discharged Gulf Stream water in the Slope Sea. Larvae of this assemblage originated from oceanic and shelf regions south of Cape Hatteras. Several members of this assemblage utilize habitats in the Middle Atlantic Bight (MAB) as juveniles (Pomatomus saltatrix, Peprilus triacanthus) and other members of the assemblage may share this life cycle (Mugil curema, Sphyraena borealis, Urophycis regia). A Slope Sea assemblage was found in all water masses, and was composed of epi‐ and mesopelagic fish larvae, as well as larvae of benthic shelf/slope residents. Larvae of one member of this assemblage (U. tenuis) are spawned in the Slope Sea but cross the shelf‐slope front and use nearshore habitats for juvenile nurseries. A MAB shelf assemblage was found in MAB shelf water and was composed of larvae that were spawned on the shelf. Some of these species may cross into the Slope Sea before returning to MAB shelf habitats (e.g. Enchelyopus cimbrius, Glyptocephalus cynoglossus). Previous studies have examined the effect of warm‐core rings on larval distributions, but this study identifies the importance of smaller‐scale features of the MAB shelf/slope front and of filaments associated with Gulf Stream meanders. In combination with these advective processes, the dynamic nature of larval distributions in the Slope Sea appears to be influenced, to varying degrees, by both vertical and horizontal behaviour of larvae and pelagic juveniles themselves.  相似文献   
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