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21.
Identification of durum wheat cultivars and monovarietal semolinas by analysis of DNA microsatellites 总被引:1,自引:0,他引:1
Microsatellites isolated in bread wheat were used to identify 20 Italian durum wheat (Triticum turgidum var. durum L.) cultivars. A total of 15 microsatellite primer pairs were tested against DNA extracted from leaf tissue, single seeds
and semolina. Twelve markers showed allelic polymorphism among the 20 cultivars, providing a total of 41 different alleles.
Firstly, an analysis of microsatellite informativeness in the chosen set of durum wheat cultivars was made and a set of highly
polymorphic microsatellites was established. Secondly, among the most polymorphic cultivars, the minimum number of microsatellites
able to distinguish all cultivars was determined. A set of five microsatellites was found sufficient to differentiate the
durum wheat cultivars examined. The method is directly applicable to seeds and semolina, and is suitable for detecting seed
mixtures in the same seed lot.
Received: 22 February 1999 / Revised version: 19 April 1999 相似文献
22.
Whole soybeans were exposed to microwave roasting for 6, 12, and 20 min at a frequency of 2,450 MHz and were studied not only
for phospholipid composition but also for positional distribution of the fatty acids. During microwave roasting, the greatest
rate of phospholipid losses (P<0.05) was observed in phosphatidylethanolamine (PE), followed by phosphatidylcholine (PC) and phosphatidylinositol (PI),
respectively. Therefore, the effects of microwave roasting on the composition and positional distribution of the fatty acids
are likely clearer in PE than in PC or PI. However, the principal characteristics for the positional distribution of fatty
acids are still retained during microwave roasting: unsaturated fatty acids, especially linoleic, are predominantly concentrated
in the 2-position, and saturated fatty acids, especially palmitic, primarily occupy the 1-position after 12 or 20 min of roasting.
The results suggest that unsaturated fatty acids located in the 2-position are significantly protected from microwave roasting. 相似文献
23.
Christine Kenter & Christa M. Hoffmann 《International Journal of Food Science & Technology》2009,44(5):910-917
Long-term storage of sugar beet is an option to extend the processing campaign of the sugar factories in Europe. In the present study, changes in the processing quality of sugar beet were quantified during 110 days of storage at 7 and 20 °C. During storage, the concentration of sucrose decreased whereas K, Na, amino N, betaine, invert sugar and raffinose accumulated in the beets, i.e. quality was impaired markedly. At 7 °C, the changes in sucrose concentration were relatively small but the formation of invert sugar and raffinose caused considerable losses in beet quality. Thus, long-term storage at low temperature is appropriate to prolong the campaign but processing costs will increase. Quality assessment with two formulae showed that measurements of K, Na and amino N are insufficient to evaluate stored sugar beets for recoverable sugar. Due to its increase in storage, the concentration of invert sugar should also be taken into account. 相似文献
24.
Statistical analysis on Sicilian olive oils 总被引:1,自引:0,他引:1
Marco D’Imperio Giacomo Dugo Maria Alfa Luisa Mannina A.L. Segre 《Food chemistry》2007,102(3):956-965
A robust multivariate statistical procedure applied to an accurate gas chromatography (GC) analysis was used to analyze 1004 monovarietal and multivarietal Sicilian extra virgin olive oils coming from 22 cultivars of different geographical areas of Sicily and collected in nine years (1993, 1995, 1996, 1997, 1998, 1999, 2000, 2001 and 2002). The effect of the cultivar, of pedoclimatic conditions as well as of the year of harvesting on the olive oil fatty acid composition and therefore on their classification was investigated. Oleic, linoleic and palmitic fatty acids, important for the nutritional properties of an olive oil, showed a crucial rule in the characterization of olive oils. 相似文献
25.
J. Jang Y. C. Yang G. H. Zhang H. Chen J. L. Lu Y. Y. Du 《International Journal of Food Properties》2013,16(3):608-617
Many volatiles in fresh tea leaf are in the forms bound with glycosides and they are released by action of ß–primeverosidase and ß-glucosidase during tea processing. Effect of ultra-violet B on release of volatiles in fresh tea leaves of two tea cultivars, “Maoxie” and “Anhui-9,” were investigated. Types of volatile and their concentration increased when ultra-violet B was applied at 3.0 μmol m?2 s?1 for 2 h and then decreased as the irradiation was extended to 6 h. The relation of expression of ß–primeverosidase and ß-glucosidase genes to the release of volatiles were also discussed. 相似文献
26.
Susanne Schmidt Michaela Zietz Monika Schreiner Sascha Rohn Lothar W. Kroh Angelika Krumbein 《Food chemistry》2010
The aim of this study was to determine the composition and concentration of flavonoid aglycones in kale, the dependence on genotype and their interaction with decreasing temperature and global radiation. Eight kale cultivars, comprising hybrid and traditional, old cultivars, were grown in a field experiment and harvested four times at 4-week intervals. The traditional, old cultivars in particular contained high concentrations of flavonoids. In all of the investigated cultivars, kaempferol was the main flavonoid aglycone, followed by quercetin and isorhamnetin, which was quantified in six of the eight cultivars. Furthermore, in six of the eight cultivars, the total concentration of flavonoids remained unchanged with decreasing temperature and global radiation. The quercetin concentration increased in five of these six cultivars, whereas the kaempferol concentration decreased. Interestingly, the quercetin-to-kaempferol ratio increased in all of the investigated cultivars, despite the fact that the radiation level decreased, suggesting that the impact of the decline in temperature could be responsible for this effect. 相似文献
27.
The effects of cultivar, growing location and year on physicochemical and cooking characteristics of field pea (Pisum sativum) were investigated and the relationship between these characteristics was determined. Six diverse field pea cultivars were grown in five different growing locations for two subsequent years (2006 and 2007). Cultivar, location and year had a significant effect on the seed weight, seed size, water hydration capacity, cooking time and firmness of cooked peas. Significant cultivar and location differences in protein, starch, crude fibre, fat, ash and phytic acid contents of peas were observed. Most of the traits were significantly affected by the interactions: cultivar-by-location, cultivar-by-year and location-by-year. Both seed weight and seed size were negatively correlated with crude protein and crude fibre contents. Cooking time was negatively correlated with crude fibre, ash and phytic acid contents, but positively correlated with firmness and starch content. A significant positive correlation was observed between ash content and phytic acid level in peas. 相似文献
28.
29.
André de Villiers Pavel Majek Frederic Lynen Andrew Crouch Henk Lauer Pat Sandra 《European Food Research and Technology》2005,221(3-4):520-528
The phenolic content of South African wines was investigated for the purpose of their classification according to variety or cultivar. Twenty-two phenolic compounds were quantified by liquid chromatography in 55 red wines of five varieties and in 38 white wines of three varieties. Data were compared to literature values reported for wines from across the globe. ANOVA was used to determine significant concentration differences between the different varieties. Further grouping of the data was investigated by principal component analysis and cluster analysis. Finally, linear discriminant analysis was used to derive classification functions for the effective recognition of red and white wine varieties which allowed 100.0% and 97.4% correct recognition of red and white wines, respectively. 相似文献
30.
南方主要鲜食葡萄品种的叶片形态指标鉴别研究 总被引:2,自引:0,他引:2
本文根据Galet的葡萄叶形结构测定原理,用多元判别和计算机图形分析,对我国南方主要栽培的4个鲜食葡萄品种(巨峰、藤稔、美人指、希姆劳特)的叶片形态参数进行数值化鉴别.结果表明,测量的7个叶形结构参数在区分4个鲜食葡萄品种上有不同的作用,同时根据叶片测量数据,绘制判别分布图和叶形结构参数均值脸谱图形,这有利于更好的对葡萄品种进行鉴别. 相似文献