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排序方式: 共有4401条查询结果,搜索用时 15 毫秒
991.
The present study was undertaken to evaluate the effects of high protein (soybean protein or casein) on the balance between production of free radicals and antioxidant level in digestive organs of mice. For this purpose, male (C57BL/6J) mice were adapted to experimental diets containing soybean protein or casein with 20% (normal protein diets, NPDs) or 60% (high protein diets, HPDs), and HPDs supplemented with 0.06g/kg cysteamine. After two weeks of feeding, oxidative and antioxidative parameters in duodenum, liver and pancreas were measured. The results show that ingestion of high protein markedly increased contents of superoxide anion and malondialdehyde (MDA), decreased activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and Na+ K+-ATPase, and content of reduced glutathione (GSH) in digestive organs of mice (P<0.05). Levels of oxidative parameters were lower and antioxidant capacity of both enzyme and non-enzyme was higher in mice fed with soybean protein than those fed with casein. In groups fed HPDs supplemented with cysteamine, oxidative stress was mitigated. However, oxidative parameter levels were still higher than those of NPD-fed groups. The present study indicates that ingestion of high protein diets could result in an imbalance between oxidant and antioxidant, and thus induce oxidative stress in digestive organs of mice. The oxidative damage was smaller in mice fed with high level of soy protein in comparison with casein. 相似文献
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994.
Arnaud Hallier Sylvie Chevallier Thierry Serot & Carole Prost 《International Journal of Food Science & Technology》2008,43(7):1253-1262
The freezing-thawing effect on the colour of raw fillets and on the texture of cooked fillets of European catfish ( Silurus glanis ) was studied. European catfish coming from two rearing conditions occurring in France were analysed by sensory and instrumental measurements. Fillets of European catfish became lighter, yellower and less bright after a freezing-thawing cycle. An increase in hardness and a decrease in resilience, disintegration and shear resistance were also highlighted after a freezing-thawing cycle. We could make the hypothesis that these variations of colour and texture were due either to mechanical damage or muscle protein denaturation. Fillets also became less juicy after a freezing-thawing cycle because of a loss of water-holding capacity. 相似文献
995.
Mara V. Galmarini Carolina Schebor María C. Zamora & Jorge Chirife 《International Journal of Food Science & Technology》2009,44(10):1869-1876
Use of trehalose as a novel drying aid to produce freeze-dried strawberry puree was studied and compared with conventional drying aids for fruit purees, namely sucrose and maltodextrin (MD). Glass transition temperature ( T g ), colour, sensory profile and consumer preference were determined. Purees dried with MD and/or trehalose presented higher T g values as compared to sucrose. Sensory evaluation indicated that samples dried with trehalose retained fresh strawberry aroma and flavour, keeping a good sweetness/sourness balance, while puree dried with sucrose was mostly sweet. Addition of MD caused an increase in products visual viscosity and sourness, attributes which were negatively correlated to preference. Trehalose presented several advantages for increasing the quality of freeze dried fruit purees. It raised T g , gave an adequate sweetness/sourness balance, and allowed a better perception of fresh strawberry flavour. 相似文献
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997.
The role of volatile compounds on aroma and flavour perception in coloured raw carrot genotypes 总被引:1,自引:0,他引:1
Stine Kreutzmann Anette K. Thybo Merete Edelenbos & Lars P. Christensen 《International Journal of Food Science & Technology》2008,43(9):1619-1627
Quantitative analyses of volatile compounds isolated from raw carrots were combined with sensory analysis in order to identify the role of these compounds on aroma and flavour perception in coloured carrots. A sensory map of carrots with different colours was developed, the content of the isolated volatiles was determined and the role of these compounds for harsh flavour perception in raw coloured carrots was evaluated using multivariate data analysis. The sensory map showed that the coloured carrots formed distinct groups within the sensory profile. The orange genotypes were characterised by having significantly higher intensities in carrot flavour and aroma, while the reverse was true for the yellow genotypes. The purple genotype was characterised by having significantly higher intensity in sickenly sweet flavour and nutty flavour, and the red genotype was characterised by having significantly higher intensities in green aroma and flavour, bitterness and burning aftertaste. From the multivariate data analysis it was concluded that the isolated terpenes do correlate to the harsh flavour attributes. 相似文献
998.
Bangzhu Peng Tianli Yue & Yahong Yuan 《International Journal of Food Science & Technology》2009,44(3):610-615
Aroma components play an important role in the quality of cider. To understand the contribution of every component to cider aroma quality, major aroma components present in ten ciders processed with different technological methods with different yeasts and apple orchards were determined by Headspace-solid phase microextraction–gas chromatography–mass spectrometry and internal standard method. Experimental results by principal component analysis indicated that ethyl acetate, acetic acid isobutylester, isopentylacohol acetate, ethyl caprylate, ethyl 4-hydroxybutanoate, isopentylalcohol, 3,4,5-trimethyl-4-heptanol, nonyl alcohol, 3-methylthio-1-propanol serve as the key aroma components in cider from Shaanxi (China) fuji apple. A model was established and verified for evaluating aroma quality based on factor analysis by comparing with the sensory evaluation method. 相似文献
999.
Anna Maria Sanguinetti Nicola Secchi Alessandra Del Caro Giuseppe Stara Tonina Roggio & Antonio Piga 《International Journal of Food Science & Technology》2009,44(6):1192-1198
This study evaluated the shelf life extension of a cheese cake subjected to modified atmosphere (MAP) and active packaging (AP). Cheese cakes were packaged under different N2 /CO2 ratios (70/30 and 20/80) (MAP batches), by placing a sachet of an iron oxide-based oxygen absorber inside trays (AP batch) and with air (air batch). Changes in microbial growth, in-package gas composition, chemical–physical parameters including texture and sensory attributes were monitored for 48 days at 20 °C. AP allowed a mould-free cheese cake shelf life of 48 days, MAP extended the shelf life of samples packaged under 30% and 80% CO2 up to 14 and 34 days, respectively, whereas tarts stored with air spoiled after 7 days. MAP resulted in a significant increase in hardness after 14 days of storage, whereas AP tarts recovered the initial texture after 48 days. Panellists judged AP tarts over the acceptability threshold during the whole shelf life of cheese tarts. 相似文献
1000.
Mears Ryan P.; Boutros Nash N.; Cromwell Howard C. 《Canadian Metallurgical Quarterly》2009,123(2):315
Inhibitory gating (IG) is a basic central nervous system process for filtering repetitive sensory information. Although IG deficits coincide with cognitive and emotional dysfunction in a variety of neuropsychiatric disorders, limited research has been completed on the basic, functional nature of IG. Persistent IG occurs in rat prelimbic medial prefrontal cortex (mPFC), a crucial site for modulating emotional learning. To investigate the interaction of affect and IG, we recorded local field potentials (LFP) directly from prelimbic mPFC and examined the influence of tone-shock fear conditioning (FC) on IG. Behavioral reactions during IG were observed before and after FC, and increase of orienting response after FC indicated induction of tone-shock association. After FC, some components of LFP response exhibited short-term weakening of IG. On a subsequent day of recording, IG strengthened for all LFP components, but individual components differed in their particular changes. Affective regulation of IG represents an important factor influencing within-subject IG variability, and these results have implications for understanding the role of rapid, implicit neural coding involved in emotional learning and affective disruption in psychiatric disease. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献