饮料中常用天然色素的研究进展

色素作为一种重要的食品添加剂,广泛应用于食品工业中,常用的色素包括人工色素和天然色素.本文介绍了三种饮料常用的天然色素,即叶绿素铜钠盐、β-胡萝卜素和天然苋菜红色素.详尽论述了这些天然色素的理化性质、生理功能和制备方法.     

饮料中常用天然色素的研究进展

色素作为一种重要的食品添加剂,广泛应用于食品工业中,常用的色素包括人工色素和天然色素.本文介绍了三种饮料常用的天然色素,即叶绿素铜钠盐、β-胡萝卜素和天然苋菜红色素.详尽论述了这些天然色素的理化性质、生理功能和制备方法.     

天然β-胡萝卜素的制备及应用

天然β-胡萝卜素是重要的食品添加剂和食品强化剂,主要用作色素和营养强化剂。近些年来,β-胡萝卜素在保健和医疗领域中的应用也日益得到了人们的重视。本文简述了天然β-胡萝卜素的制备原理、应用市场。摘要用第三人称,不要用“本人、本文、作者、我们、笔者”作主语     

β-胡萝卜素的降解及其对食品体系的影响

β-胡萝卜素是食品中的天然色素和重要的营养物质,它在食品加工或贮藏过程中易发生降解,进而影响食品的风味、营养价值、颜色和安全性。β-胡萝卜素的降解方式主要包括热裂解、热氧化降解、化学氧化降解、光氧化降解和酶促降解等,其降解产物和降解方式与降解条件关系密切。影响β-胡萝卜素降解的主要因素包括氧气、食品添加物和水分活度。今后应重点研究微生物发酵、食品成分以及加工技术对β-胡萝卜素降解的影响,以及防止食品中β-胡萝卜素降解的措施和β-胡萝卜素降解产物风险性评估。     

天然β—胡萝卜素的制备及应用

天然β－胡萝卜素是重要的食品添加剂和食品强化剂，主要用作色素和营养强化剂。近些年来，β－胡萝卜素在保健和医疗领域中的应用也日益得到了人们的重视。本文简述了天然β－胡萝卜素的制备原理、应用及市场。     

β-胡萝卜素乳状液研究进展

β-胡萝卜素是类胡萝卜素之一,是广泛存在的天然色素。β-胡萝卜素为脂溶性物质,将其制成乳状液不仅可以解决其溶解性的问题,还可以提高其生物利用率及抗氧化活性,因此其在食品、饮料、药品等行业中有广泛的应用前景。本文介绍了β-胡萝卜素及其乳状液的基本性质和制备方法,简述了新型壁材包裹β-胡萝卜素乳状液的研究进展,并对其发展前景做出展望。     

胡萝卜素产生菌Cr-1的诱变和选育

<正> 前言 以β—胡萝卜素为主体的胡萝卜素类色素,以它呈现的艳丽色彩已被人们用作食品着色剂和饮料增色剂。更引人注目的是,β—胡萝卜素被动物和人体吸收以后转变成维生素A,因此可以作为营养添加剂。近来一些资料表明:胡萝卜素还具有防血管硬化、抑制癌细胞增生以及抗衰老等功能,所以引起国内外学者关注。尤其是微生物发酵合成的胡萝卜素避免了化学合成色素造成的潜在     

为健康增值的天然胡萝卜素

<正> 多年来,食品加工商一直使用人工合成的β-胡萝卜素对食品进行着色。不过,这种做法已经过时。随着天然胡萝卜素的开发与应用,它除了可以作为食用色素外,还含有高度的营养价值,为食品产品带来附加值。 有助增进健康 时下消费者对天然产品的需求日益增加,追求健康已经成为—种时尚。有研究表明,类胡萝卜素具有潜在的特性,能帮助预防心脏病、癌症和延缓老化及视力衰退。此外,研究又指出,这种预防作用是来自一系列的类胡萝     

化学合成β-胡萝卜素和天然β-胡萝卜素（发酵法）的鉴别区分初探

胡萝卜素具有良好的抗氧化性,在营养食品、保健品等领域应用广泛。与人工合成产品相比,发酵法得到的天然β-胡萝卜素表现出更显著的生物学功能。开发了一种有效鉴别天然β-胡萝卜素(发酵法)和合成-胡萝卜素的方法,即通过γ-胡萝卜素的检测(HPLC法)、丙酮或环己烷等溶剂残留的检测(GC法)以及三苯基氧膦的检测(HPLC法)等一种或多种方法的综合运用,判断β-胡萝卜素样品是否为合成来源,或是天然β-胡萝卜素(发酵法)中是否添加了一定量的合成β-胡萝卜素。     

枸杞色素的分离及其冷冻干燥技术的初步研究

枸杞子是我国传统名贵中药材,其色素含丰富的类胡萝卜素,是枸杞中重要的生理活性成分之一。利用离心和超滤技术分离枸杞鲜果色素,再经冷冻干燥制成枸杞色素粗粉,其中β-胡萝卜素含量达6%以上,可作为食品和化妆品和添加剂,也是提取β-胡萝卜素的理想原料,具有广阔的开发前景。     

Heterogeneity of subunit composition in lupin globulins. Comparison of proteins from a single seed and from a number of seeds

The subunit compositions of a legumin-like (globulin 8) and a vicilin-like protein (globulin 4) extracted from a plurality of seeds and from a single seed both in commercial and in a selected cultivar of Lupinus albus were studied. In the case of globulin 4, a very similar number of bands were observed in SDS-PAGE, in the protein extracted from a batch of seed and in the same globulin isolated from a single seed. For globulin 8 the SDS-PAGE pattern showed fewer subunits in the protein from the batch of seeds than in that from a single seed. This is more pronounced in the single seed and in the plurality of seeds of a selected cultivar. Reasons for this behaviour are discussed.     

Effect of carbohydrates on arterial pressure. An experimental study]

The effect of incorporation of sugar in a diet on a level of arterial pressure in 120 rats Wistar was examined. The replacement of 50% of starch by sugar in the balanced diet with a normal content of protein and white salt did not have a profound influence on a pressor effect. However on a background of an abundant content of white salt in a diet protein and fat balanced, the incorporation of sugar in a diet resulted in additional increase of arterial pressure (+27.27 mm of a hg) in comparison with a saline diet without sugar (p < 0.001). The sugary diet with normal content of white salt bring to evident pressor effect (+6.60 mm of a hg) at deficiency of protein (p < 0.001), though on others variants of protein deficiency diets the slight tendency to a drop of arterial pressure was observed. The causes of ambiguous changes of arterial pressure in a protein deficiency remain unclear.     

25—STUDIES IN FRICTION-TWISTING PART I: A SIMPLE TREATMENT OF THE SLIPPING MODE

The paper gives a vectorial treatment of a simple friction-twisting situation in which a ‘yarn’ passes over a moving belt in a slipping mode in a straight-line path with constant frictional increment. The treatment leads to theorems concerning the asymptotic values of torque, equal to that in the hypothetical non-slipping rotational mode, and tension change. Comments on complexities of the real friction-twisting situation in texturing are made.     

A contaminant trap as a tool for isolating and measuring the desorption resistant fraction of soil pollutants

Bioremediation of contaminated soils often leaves a desorption-resistant pollutant fraction behind in the soil, which in the present study was isolated with a combination of diffusive carrier and infinite diffusive sink. Such a diffusive sink was made by casting a composite of silicone and activated carbon into the bottom of a large glass. Field-contaminated soil samples were then suspended in a cyclodextrin solution and incubated in such glasses for the continuous trapping of PAH molecules during their release from the soil matrix. The PAH concentrations remaining in the soil were determined by exhaustive extraction and compared with a biodegradation experiment. The concentration decline in the first soil was faster in the contaminant trap than in the biodegradation experiment, but the halting of the biodegradation process before reaching the legal threshold level was well indicated by the contaminant trap. The PAH concentrations in the second soil hardly decreased in the traps at all, in good agreement with the biodegradation experiment. The PAHs in this soil appeared to be "stuck" by strong sorption. The contaminant trap proved to be a practical approach to the isolation and quantification of the desorption-resistant PAH fraction.     

有机酯在低酒精度水溶液中的贮存变化分析

低度白酒中有机酯在酒体中的变化一直是白酒行业中非常热门的话题，通过对有机酯在单纯低度酒精-水溶液的贮存变化和添加对应有机酸后的变化从而验证有机酯在低度酒精-水溶液中的变化规律属于有机酯的酸水解过程，对应酸在其中起催化剂的作用。     

A simple formulation and solution to the replacement problem: a practical tool to assess the economic cow value, the value of a new pregnancy, and the cost of a pregnancy loss

This study contributes to the research literature by providing a new formulation for the cow replacement problem, and it also contributes to the Extension deliverables by providing a user-friendly decision support system tool that would more likely be adopted and applied for practical decision making. The cow value, its related values of a new pregnancy and a pregnancy loss, and their associated replacement policies determine profitability in dairy farming. One objective of this study was to present a simple, interactive, dynamic, and robust formulation of the cow value and the replacement problem, including expectancy of the future production of the cow and the genetic gain of the replacement. The proven hypothesis of this study was that all the above requirements could be achieved by using a Markov chain algorithm. The Markov chain model allowed (1) calculation of a forward expected value of a studied cow and its replacement; (2) use of a single model (the Markov chain) to calculate both the replacement policies and the herd statistics; (3) use of a predefined, preestablished farm reproductive replacement policy; (4) inclusion of a farmer's assessment of the expected future performance of a cow; (5) inclusion of a farmer's assessment of genetic gain with a replacement; and (6) use of a simple spreadsheet or an online system to implement the decision support system. Results clearly demonstrated that the decision policies found with the Markov chain model were consistent with more complex dynamic programming models. The final user-friendly decision support tool is available at http://dairymgt.info/ → Tools → The Economic Value of a Dairy Cow. This tool calculates the cow value instantaneously and is highly interactive, dynamic, and robust. When a Wisconsin dairy farm was studied using the model, the solution policy called for replacing nonpregnant cows 11 mo after calving or months in milk (MIM) if in the first lactation and 9 MIM if in later lactations. The cow value for an average second-lactation cow was as follows: (1) when nonpregnant, (a) $897 in MIM = 1 and (b) $68 in MIM = 8; (2) when the cow just became pregnant,(a) $889 for a pregnancy in MIM = 3 and (b) $298 for a pregnancy in MIM = 8; and (3) the value of a pregnancy loss when a cow became pregnant in MIM = 5 was (a) $221 when the loss was in the first month of pregnancy and (b) $897 when the loss was in the ninth month of pregnancy. The cow value indicated pregnant cows should be kept. The expected future production of a cow with respect to a similar average cow was an important determinant in the cow replacement decision. The expected production in the rest of the lactation was more important for nonpregnant cows, and the expected production in successive lactations was more important for pregnant cows. A 120% expected milk production for a cow with MIM = 16 and 6 mo pregnant in the present lactation or in successive lactations determined between 1.52 and 6.48 times the cow value, respectively, of an average production cow. The cow value decreased by $211 for every 1 percentage point of expected genetic gain of the replacement. A break-even analysis of the cow value with respect to expected milk production of an average second-parity cow indicated that (1) nonpregnant cows in MIM = 1 and 8 could still remain in the herd if they produced at least 84 and 98% in the present lactation or if they produced at least 78 and 97% in future lactations, respectively; and (2) cows becoming pregnant in MIM = 5 would require at least 64% of milk production in the rest of the lactation or 93% in successive lactations to remain in the herd.     

Comparative action of cathepsins B and L on intramuscular collagen as assessed by differential scanning calorimetry

Intramuscular beef collagen of different degrees of reticulation was treated with cathepsin L obtained from chicken liver and a commercial cathepsin B prepared from beef spleen. It was shown that, in the absence of calcium, both proteinases caused a decrease in the initial temperature of denaturation whereas the total enthalpy of denaturation was unaffected. Treatment with cathepsin B resulted in the appearance of a new peak of denaturation at a lower temperature (≈ 44°C), a change wholly comparable with that obtained previously when intramuscular beef collagen was treated with a collagenase from Clostridium histolyticum. There was no such change with cathepsin L. The addition of 20 mM CaCl(2) to the incubation buffer brought about a shift in the total enthalpy of denaturation when collagen was treated with cathepsin L; in contrast, no additional effect was observed in cathepsin B treatments. These findings led to the suggestion that cathepsins B and L have a different mode of action on collagen and that there may be a similarity in the mechanism of action between cathepsin B and the bacterial collagenase.     

Increasing access to smoking cessation treatment in a low-income, HIV-positive population: the feasibility of using cellular telephones.

This study examined the feasibility of using cellular telephones to improve access to smoking cessation counseling in a low-income, HIV-positive population. Two pilot studies were conducted: (a). A survey of interest and barriers in participating in a smoking cessation intervention (n=49) and (b). a cellular telephone smoking cessation intervention in which participants were provided with free cellular telephones and received six telephone counseling sessions over a 2-week period (n=20). A primary care clinic serving a multiethnic, medically indigent, HIV-positive population served as the setting. Demographics and smoking status were assessed by self-report and expired-air carbon monoxide testing. In study 1, participants reported multiple barriers to participating in a smoking cessation intervention, including transportation, transience, and telephone availability. However, they also reported a high level of interest in participating in a smoking cessation intervention, with the greatest interest in a cellular telephone intervention. In study 2, 19 of the 20 participants successfully completed 2 weeks of smoking cessation counseling with a 93% (106 of 114 calls) contact rate. A total of 19 participants made a quit attempt, and the 2-week end of treatment point-prevalence abstinence rate was 75%. The provision of cellular telephones allowed for the implementation of a proactive telephone smoking cessation intervention providing an underserved population with access to care. Cellular telephones also may provide unique benefits because of the intensity of counseling and support provided as well as the ability to provide counseling in real-world, real-time situations (in vivo counseling).