Effect of the absence of lipoxygenase isoenzymes on the storage characteristics of rice grains

Three varieties of paddy rice with and three varieties without lipoxygenase (LOX) isoenzymes were stored at room temperature, in dark conditions for 42 months. Insect damage and viability were investigated during that time. Varieties without LOX-1,2 and their offspring were screened with a rapid method of estimating LOX isoenzymes, and subjected to an accelerated-ageing experiment. The results indicated that in varieties without LOX-1,2, after long storage, rice quality was normal, but for varieties with LOX-1,2, rice quality deteriorated. With increase of storage time, the germination rate of the seed of most varieties decreased greatly except for varieties without LOX-1,2 where there was almost no change in the germination rate. In varieties without LOX-1,2 and their offspring, after an accelerated ageing experiment the germination rate of some varieties changed slowly, but with others, the germination rate changed quickly. This indicated that a definitive factor, which influenced the life of seeds, may be the loss of LOX-1,2. During storage, there was also a significant difference in the degree of insect damage. In varieties without LOX-3 insect damage was lower, but in varieties with LOX-3 insect damage was higher. Therefore, the absence of LOX-3 may be very important in insect resistance in rice grain.     

Evaluation of the phenolic content,antioxidant activity and colour of Slovenian honey

Honey samples from the seven most common honey types in Slovenia were screened for total phenolic content by the modified Folin–Ciocalteu method, for potential antioxidant activity using the ferric reducing antioxidant power (FRAP) assay and by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method for antiradical activity. In addition the colour characteristics of honey samples were analysed. The results of the study showed that total phenolic content, antioxidant activity and colour parameters differ widely among different honey types. Phenolic content expressed as gallic acid equivalent ranged from 44.8 mg/kg in acacia honey to 241.4 mg/kg in fir honey. Antioxidant activity was the lowest in the brightest acacia and lime honeys and the highest in darker honeys, namely fir, spruce and forest. The colour of the Slovenian honeys, analysed in this study was very variable and ranged from pale yellow to dark brown. Correlations between the parameters analysed were found to be statistically significant (p < 0.05).     

“中国十大文化名酒”成功案例系列报道之四—文化名酒的口感与工艺特色

国酒茅台集酱香、窖底香和醇甜香于一体,发酵时间长,环境、微生物独特,水质好、无污染。炉州老窖无色透明、窖香幽雅、绵甜爽净、柔和协调、尾净香长、风格典型;窖龄长,粮、曲、水独特,工艺管理严谨。剑南春集五粮之精华,香、醇、净、爽,儒雅柔香。酒鬼酒酱香幽雅、清香灵秀、浓香醇厚。道光廿五酒醇香、幽香、雅香。汝阳杜康、双沟大曲、宝丰大曲、今世缘等文化名酒,也各具独特风格个性。（孙悟）     

Systematic clinical examinations for identification of latent udder health types in Danish dairy herds

A cross-sectional study was conducted to explore the applicability of systematic clinical examinations of udders as an additional tool for the evaluation of udder health status on dairy farms. During 2000, each of the 16 dairy farms was visited 5 times; 20 cows per farm were chosen at random at each visit for clinical udder examination immediately after milking. The clinical examination included both pathological and morphological variables. One examination per cow was included in the analysis (n = 707 cows). Principal component analysis (PCA) was performed in 3 steps. First, 19 variables characterizing udder and teats were analyzed (PCA 1). Second, the variables parity and stage of lactation were included (PCA 2). Finally, somatic cell count (SCC) and milk yield (PCA 3) were included. The PCA resulted in 4 components that explained 30% of the variation of the data: 1) small udder, 2) distressed udder, 3) mastitis udder, and 4) soiled udder. Variables with high positive correlation to the "small udder" were small udder shape, short teats, and first parity. Impaired teat surface, hard udder texture, and a long udder shape were related to the "distressed udder." The "mastitis udder" was characterized by the clinical variables asymmetry between front quarters, asymmetry between hind quarters, knotty tissue, and acute clinical mastitis. Reduced milk yield and high SCC were related to the "mastitis udder," whereas low SCC was related to the "small udder." The "soiled udder" was related to early lactation. Including this information in the assessment of udder health may be of substantial value for data analysis in farms with suspected under-reporting of clinical mastitis.     

Gas chromatographic-olfactometric characterization of aroma active compounds in sun-dried and vacuum-dried tarhana

The influence of drying methods on the aroma active volatiles of sun-dried tarhana (SDT) and vacuum-dried tarhana (VDT) were compared using headspace SPME, GC-O and GC-MS. Although vacuum drying reduced the total amount of volatiles as compared to SDT (total FID peak area), more aroma active material was retained with VDT (total olfactory peak area). Vacuum drying retained a greater number of aroma active components (41) whereas the sun-dried method retained only 23. Aldehydes were the largest single class of aroma compounds in both types of tarhana: 17 in VDT and 10 in SDT. Other differentiating aroma compounds include alcohols, terpenes, and phenols such as geraniol, terpinolene, and 4-vinylguaiacol among others. A total of 22 aroma active components were present in greater amounts in the VDT versus only four aroma compounds present in greater amounts in the SDT.     

Interactions between anthocyanins and organic food molecules in model systems

The interactions between different glucosidic anthocyanins (pelargonin, cyanin, delphinin, malvin and petunin) and some organic compounds (lactic, galacturonic, tannic, phenolic and sinapic acids; pyrogallol, furfural, pectin, cellulose, hydrolitic lignin) which are present in food‐stuffs were investigated at pH 3.0–4.3 and 25 °C. The interactions were monitored by means of u.v.‐VIS spectra and their different behaviours were highlighted by following changes in absorbance over a range of wavelengths (Δλ and ΔA). Significant effects on absorbance were detected and are discussed in terms of the phenomenon of co‐pigmentation.     

掺La的锆锡钛酸铅陶瓷制备及介电性能

锆锡钛酸铅(Pb(Zr,Sn,Ti)O3)系列陶瓷具有优异的铁电、压电等性能,为制备高质量的陶瓷材料,采用传统的氧化物固相烧结工艺,制备了一组镧(La)元素微量掺杂的锆锡钛酸铅陶瓷,并对样品的铁电和介电性能进行测试表征.结果表明,所采用的制备工艺良好,成瓷好,4组陶瓷样品的组分位于铁电/反铁电相界附近,铁电相和反铁电相共存.     

带Poisson跳和Markovian转换的随机时滞泛函微分方程数值解的收敛性

为了近一步研究带Poisson跳和Markovian转换的随机时滞泛函微分方程数值解的收敛性问题,文中给出带Poisson跳和 Markovian 转换的随机时滞泛函微分方程 Euler 数值解迭代格式。在弱条件下,利用Laypunov泛函方法和随机分析理论证明了数值解依概率收敛于方程的解。所得结果覆盖了许多非线性时滞微分方程已经存在的某些理论,而且实验说明此结论比以往的结论更容易验证。     

正二十烷／海藻酸钠微胶囊的锐孔凝固浴法制备

为改善织物的调温性能,采用锐孔凝固浴法,以正二十烷为芯材,海藻酸钠为壁材,制备相变微胶囊。使用光学显微镜、扫描电镜、傅里叶变换红外光谱分析仪和差示扫描量热仪等测试手段对相变微胶囊的外貌形态和热性能进行分析。得到制备正二十烷／海藻酸钠相变微胶囊的最佳工艺条件为：海藻酸钠的质量分数2?5％,CaCl2的质量分数7?0％,芯材与壁材质量比1∶3。在最优条件下制备的相变微胶囊表面光滑,平均粒径为56?7μm,相变潜热为117?3 J／g,微胶囊的耐热性能良好,明显地改善了织物的调温性能。     

棕色绵糖

介绍了国外市场上被认作具有特殊性能的棕色绵糖，并叙述了棕色绵糖的生产方法和应用范围，旨在为制糖企业开发新品种及提高附加值提供技术基础。