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排序方式: 共有480条查询结果,搜索用时 31 毫秒
61.
62.
通过对比我国现行GB 50009-2006建筑结构荷载规范与IS875∶1987印度建筑物设计荷载(不包括地震)规程的有关规定,从荷载系数以及不同极限状态下选取的荷载组合两个方面,分析两国荷载规范的异同,为涉外工程的结构设计提供参考。 相似文献
63.
Amit Laddi Neelam Rup Prakash Shashi Sharma Himanka Sekhar Mondal Amod Kumar Pawan Kapur 《Journal of food engineering》2012
In this research work, an attempt was made to discriminate different grades of black crush-tear-curl (CTC) tea based upon their physical attributes such as color of brewed liquor, texture, size and shape of the tea granules obtained by machine vision technique. The principal component analysis (PCA) was applied over two types of data. First, tea samples with seven different quality grades but same mechanical grading and second, samples with same quality grade but nine different mechanical grades (Brokens, Fannings and Dust) were considered for analysis, respectively. The results of PCA showed that best discrimination (100%) in both types of data was given by color attributes only. Correlations among tea samples and physical attributes were determined. Based upon these results it may be concluded that color only attributes are the most significant and sufficient for quantification of tea quality whereas other physical attributes contribute so little to quality estimation that they may be ignored. 相似文献
64.
Seasonal variations of heavy metals concentrations and overall chemical compositions were determined in chub mackerel caught in the Southern Sea of Korea. The average mercury and lead content varied between 0.04 and 0.08 mg/kg and between 0.01 and 0.02 mg/kg, respectively. Seasonal variations were not detected in lead, but mercury displayed maximal values in winter (P < 0.05). A distinct seasonal pattern was found in crude fat content with maximal values in December and minimal values in April. Fatty acid composition showed that monounsaturated fatty acids levels were the highest in August, while polyunsaturated fatty acids (PUFA) levels were the highest in April. The major contributing factors to the seasonal variation of PUFA amounted to 20:5n-3 and 22:6n-3. The total amino acids content varied from 180.6 to 187.7 mg/g. There were no significant seasonal variations in total amounts of amino acids. Practical Application: Mackerel (Scomber japonicus) is one of the most important fishing resources in Korea. The effects of polyunsaturated fatty acids (PUFA) on the human body have been identified, and consequently, the intake of fish lipids has steadily increased among the human population. There have been few studies on safety and alterations in chemical composition of mackerel attributed to seasonal fluctuations. Therefore, the results presented in this study could be used to improve the safety and nutrition information available to consumers. 相似文献
65.
KATHRYN WANDERER CHAPMAN IFAT SAGI KEUM TAEK HWANG JOE M. REGENSTEIN 《Journal of food science》1993,58(6):1208-1211
Extra-cold storage (?30 and ?40°C) of mackerel (Scomber scombras) mince and fillets showed lower free fatty acid formation. Extra-cold storage (-30°C) of white hake (Urophycti tenuis) fillets produced fish with better quality based on sensory and chemical indices. The colder the storage temperature, the less firm the hake mince and fillets. Ascorbic acid accelerated cohesiveness development of mackerel mince and fillets. Over time, the quality of the hake and mackerel decreased according to sensory and chemical indices. They became tougher and generally more cohesive. 相似文献
66.
67.
Thazhakot V Sankar Alappat Ramachandran 《Journal of the science of food and agriculture》2005,85(4):563-568
The characteristics and stability of natural actomyosin (NAM) from rohu (Labeo rohita), catla (Catla catla) and mrigal (Cirrhinus mrigala) were investigated. The total extractable actomyosin (AM) was higher (7.60 mg ml?1) in the case of rohu compared with that from catla and mrigal (5 mg ml?1). Although the specific AM ATPase activity was similar (0.43–0.5 µmol P min?1 mg P?1) among the three species, the total ATPase activity was lower in mrigal (25 µmol g?1 meat) compared with the other species (37 µmol g?1 meat). The inactivation rate constants (kd) of AM Ca ATPase activity showed differences in the stabilities of actomyosin among these fish, the actomyosin from catla being least stable. The NAM from these species was stable up to 20 °C at pH 7.0. Catla AM became unstable at 30 °C, while rohu and mrigal AM could withstand up to 45 °C. The thermal denaturation with respect to solubility, turbidity, ATPase activity, sulphhydryl group and surface hydrophobicity showed noticeable changes at around these temperatures. Copyright © 2004 Society of Chemical Industry 相似文献
68.
ABSTRACT: :
The effects of different fuel sources used in grilling on the physicochemical and sensory characteristics of mackerel were investigated. Oak and sawdust charcoals were used as fuel sources. The content of saturated fatty acids was increased during grilling. Histidine was the most predominant amino acid; grilling significantly increased glutamic acid. Mackerel shows a high inosine 5'-monophosphate content that is increased during grilling. Oak charcoal and sawdust charcoal contained high levels of potassium and sodium, respectively. Potassium content was increased at the surface muscle of oak charcoal grilled mackerel (OM). The flavor preference for OM was significantly (p < 0.05%) higher than for sawdust charcoal grilled mackerel. These results indicate that physicochemical and sensory properties of grilled foods can be affected by the fuel source. 相似文献
The effects of different fuel sources used in grilling on the physicochemical and sensory characteristics of mackerel were investigated. Oak and sawdust charcoals were used as fuel sources. The content of saturated fatty acids was increased during grilling. Histidine was the most predominant amino acid; grilling significantly increased glutamic acid. Mackerel shows a high inosine 5'-monophosphate content that is increased during grilling. Oak charcoal and sawdust charcoal contained high levels of potassium and sodium, respectively. Potassium content was increased at the surface muscle of oak charcoal grilled mackerel (OM). The flavor preference for OM was significantly (p < 0.05%) higher than for sawdust charcoal grilled mackerel. These results indicate that physicochemical and sensory properties of grilled foods can be affected by the fuel source. 相似文献
69.
Fresh Indian mackerel (Rastrelliger kanagurta) was exposed to gamma radiation at dosages of 0,1.5 and 3 kGy. The meat was collected and subjected to a four-step washing treatment. Homogenates of the washed meat in cold (<10°C) water exhibited apparent viscosity, which was dependent upon protein concentration. Warming the homogenate to 45°C or reduction of its pH to 3.5 by acetic acid decreased the viscosity. Proteins in the low-viscosity dispersion were stable to heating at 100°C while incorporation of NaCl at 5 mM prior to heating resulted in protein precipitation. Gamma irradiation did not affect the viscosity, solubility or stability of the muscle proteins in water. 相似文献
70.
Alok K Srivastava Ummiti J
S Prasada Rao Punaroor Haridas Rao 《Journal of the science of food and agriculture》2003,83(3):225-231
In order to predict the suitability of wheat for chapati making, 15 Indian wheat cultivars were studied for various protein characteristics in relation to chapati‐making quality. The cultivars varied considerably in their protein characteristics and chapati‐making potential. Results clearly indicated that both quantitative and qualitative characteristics of proteins influenced the chapati‐making potential of cultivars. Puffed height, the important qualitative parameter of chapati, was positively correlated with protein content (r = 0.62, p < 0.05), gluten content (r = 0.79, p < 0.01), sodium dodecyl sulphate (SDS) sedimentation value (r = 0.57, p < 0.05) and Glu‐1 quality scores of high‐molecular‐weight (HMW) subunits (r = 0.66, p < 0.01). Overall quality score of chapati was positively correlated with gluten content (r = 0.64, p < 0.01), SDS sedimentation value (r = 0.60, p < 0.05) and Glu‐1 score (r = 0.58, p < 0.05). HMW subunit composition varied considerably among cultivars. Cultivars having 5 + 10 subunits at the Glu‐1D chromosome, a protein content of about 130 g kg?1 and SDS sedimentation value around 75 ml yielded excellent chapatis, while those having 2 + 12 subunits, a protein content of about 115 g kg?1 and SDS sedimentation value around 55 ml resulted in poor chapatis. Interestingly, the presence of the 1BL/1RS chromosome in cultivars had no adverse effect on chapati quality. © 2003 Society of Chemical Industry 相似文献