共查询到19条相似文献，搜索用时 78 毫秒
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引起啤酒、白酒和澄清果汁出现混浊或沉淀的原因很多,最常见的是由蛋白质———多酚的相互作用引起的,但这些饮料一般能稳定存在,并能延缓蛋白质———多酚混浊物形成开始的时间。10多年前已有关于促使蛋白质或多酚成为混浊激活物(ＨＡ)方面的报道(Ａｓａｎｏｅｔａｌ,1982;Ｍｏｌｌ,1987),但近来的研究发现,饮料中两者的比例对混浊的形成数量起着重要的作用(Ｓｉｅｂｅｒｔｅｔａｌ,1996ｃ),这发现使我们能更好地理解一些检测ＨＡ种类的分析方法及其稳定的机制。在鉴别ＨＡ物质的特性方面,我们已经做子大量的工作(Ｍｏｌｌ,1987)。啤酒中的… 相似文献
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饮料中蛋白质——多酚的作用机制 总被引：3，自引：0，他引：3
蛋白质－多酚的相互作用是引起饮料混浊的重要原因之一。蛋白质具有混浊形成活性主要取决于它的脯氨酸含量,多酚形成混浊的能力与其分子结构有关,蛋白质与多酚的比例强烈影响到饮料中混浊的形成量。文中叙述了饮料中蛋白质－多酚的作用机制和最新进展。 相似文献
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R.T. THRELFALL J.R. MORRIS A. MAUROMOUSTAKOS 《Australian Journal of Grape and Wine Research》1999,5(1):22-26
Resveratrol has been identified as a wine component related to moderate wine consumption and a reduction in serum cholesterol levels. Processes such as wine fining that result in loss of resveratrol during winemaking are therefore of interest, and led to these present studies. A number of agents were compared and were found to lower resveratrol levels in all wines to some extent. Results from two studies (1996 and 1997) are reported. The standard addition method was used in combination with High Pressure Liquid Chromatography to calculate resveratrol levels. In Study 1 (1996), recommended maximum levels of all fining agents (Level 3), bentonite, egg white, gelatin + kieselsol and polyvinylpolypyrrolidone (PVPP), lowered resveratrol levels significantly compared to controls (Level 0). Nevertheless, addition of fining agents at Level 0 resulted in resveratrol levels that were significantly higher than those at Level 3, but resveratrol levels in wine from Level 0 were not significantly different from Level 1. In Study 2 (1997), carbon + egg white, and gelatin + kieselsol fining was studied, and their effects differed according to grape variety. Least removal of resveratrol by carbon fining occurred in wine from Cabernet Sauvignon (Vitis vinifera) whereas most removal occurred in wines from Cynthiana (Vitis aestivalis) and Noble (Vitis rotundifolia). Resveratrol levels of control wine were significantly higher than resveratrol levels of wine treated with recommended maximum addition of fining agent in all varieties. Taken overall, any addition of any fining agent lowered resveratrol levels in all wines to some extent, but complex interactions between fining agent and wine variety resulted in different regression trends. While recognising the constraints set by our particular data that could reflect unique circumstances, we are nevertheless able to infer from these trends that low levels of fining agents can be used without statistically significant loss of resveratrol. 相似文献
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Are Hugo Pripp Rob Vreeker John van Duynhoven 《Journal of the science of food and agriculture》2005,85(3):354-362
In this paper we investigate the interaction of phenolics extracted from olive oil with different food proteins (sodium caseinate, bovine serum albumin, β‐lactoglobulin and gelatin). Binding parameters are estimated using different experimental techniques: gel filtration, HPLC, isothermal titration calorimetry and NMR diffusion measurements. For comparison, the binding properties of gallic acid and tannic acid are also studied. The affinity of olive oil phenolics for the different food proteins is found to be relatively weak (compared with tannic acid). Binding constants are measured for the different phenolics in the extract: tyrosol and hydroxytyrosol do not (or very weakly) bind to the proteins, whereas other phenolics in the extract had binding constants of the order 102–104 M ?1. The binding parameters determined have been discussed in relation to the possible effect of proteins on sensory properties (bitterness) of food emulsions containing olive oil. Copyright © 2004 Society of Chemical Industry 相似文献
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本文主要对小米饮料的淀粉液化、糖化的最佳反应条件和稳定剂对小米饮料稳定性的影响进行了探讨,结果表明小米浸提液的液化最佳条件为:α-淀粉酶的加酶量6U/g淀粉,作用时间90min,作用温度70℃,pH6.5;糖化的最佳条件为:β-淀粉酶的加酶量100U/g淀粉,作用时间60min,作用温度60℃,pH5.5;稳定剂的最佳配比为:0.5%的阿拉伯胶、0.07%的瓜儿豆胶、0.07%的黄原胶、2.1%的蔗糖。 相似文献
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Background and Aims: Bentonite fining to remove protein is the most widely used treatment to prevent protein haze in white wines. Bentonite can be added at different stages during winemaking. This study aimed to determine the best time to add bentonite. Methods and Results: Unstable juices were vinified after bentonite fining of juice, or with bentonite added either early or late in fermentation. Different addition rates of bentonite were used and bentonite was either added in one or two additions. Fermentation rates were observed and protein stability and bentonite fining rates of the resultant wines were determined. Conclusions: Adding bentonite during fermentation or fining finished wines was the most efficient option in terms of amounts of bentonite required. Fermenting with bentonite present also may increase fermentation rates. Significance of the Study: Using the least bentonite necessary for heat stability is important for winemakers for quality, cost and environmental reasons. This study describes ways in which bentonite addition rates can be minimised. 相似文献
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《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(11):1805-1817
Proteinogenic wine fining agents are hidden allergens and could present a risk for consumers with allergies. Therefore, the European Parliament adopted Directive 2003/89/EC amending Directive 2000/13/EC to declare ingredients, contaminations and processing aids that are known to trigger allergic reactions. The Amendment Regulation (EU) 1266/2010 excluded the labelling of wines which are processed with hen’s egg and products thereof until 30 June 2012 to get more scientific findings. After 1 July 2012 wine fining agents have to be declared if above 0.25 mg l–1 (Regulation (EU) 579/2012 in conjunction with article 120 g of Regulation (EU) 1234/2007). The Organisation International de la Vigne et du Vin (OIV) advises this limit of detection (LOD) for potential allergenic residues of proteins. Wine fining agents are processing aids and according to the wine producer’s knowledge will be removed after coagulation by filtration or other production steps. Due to lack of scientific data, residues of fining agents in the final product could not be excluded. In this risk assessment, highly sensitive ELISA methods for ovalbumin of known origin for wine have been developed. The objective was to investigate the presence of allergen residues in wine after certain technological treatments were applied to remove the wine fining agents. For all developed ELISA methods the LODs are in the low µg l–1 range between 5 and 10 µg l–1 fining agent, whereas the LOQ varies between 5 and 80 µg l–1 fining agent. The results of the investigation of well-known wines and fining agents demonstrate that white wines fined with white or ovalbumin from hen’s egg could retain allergens. The use of certain technological procedures during wine processing leads to different results. In white wine, bentonite or sheet filtration followed by sterile filtration lead to wines containing no detectable amounts of ovalbumin. In red wine, especially the final sterile filtration removes the fining agents. 相似文献