饮料中甜味剂的应用与食品安全

食品安全问题已经成为了一个普遍的社会问题,其中有很多的食品安全问题是由于非法添加造成的。甜味剂作为一种常用的添加剂,几乎涵盖了所有的食品,我国批准使用的甜味剂有15种。随着生活水平的不断提高,人们更加重视生命健康与饮食安全,因此需要科学的渠道,让人民大众了解食品添加剂与食品安全。通过调查各种甜味剂在榆林市市场上大部分饮料中的使用情况,本研究主要对5种常用甜味剂(甜蜜素、安赛蜜、阿斯巴甜、糖精钠、三氯蔗糖)的使用情况、存在的安全问题、如何规范使用等进行了概述。以期让消费者科学的了解甜味剂与食品安全,同时在食用或购买食品时更加有科学的依据。     

高效液相色谱法同时检测食品中安赛蜜、苯甲酸、山梨酸、糖精钠的影响因素分析

目的分析高效液相色谱法(high performance liquid chromatography,HPLC)检测食品中安赛蜜、苯甲酸、山梨酸、糖精钠等添加剂含量时的各种影响因素。方法从流动相比例、流动相pH、样品基质、流动相乙酸铵浓度、柱温、标准曲线溶液储存时间等方面判断各因素对色谱分析结果的影响。结果随流动相中乙酸铵浓度降低,柱温升高,4种物质的保留时间缩短,其中乙酸铵的浓度对糖精钠的影响最大。流动相pH对安赛蜜和糖精钠保留时间无影响,而苯甲酸和山梨酸随流动相pH升高保留时间缩短,其对山梨酸影响最大。样品pH对保留时间有影响,但并不影响分析结果。乙醇含量对保留时间无影响,标准曲线溶液4℃冰箱密封保存,一周内各浓度峰面积变化不显著(P0.05)。结论安赛蜜、苯甲酸、山梨酸、糖精钠分析会受各种色谱条件影响,标准曲线溶液4℃冰箱密封保存一周内有效。     

户太8号桃红葡萄酒贮藏期香气物质损失及添加剂护香效果分析

研究户太8号桃红葡萄酒贮藏期的香气物质变化规律,并比较几种添加剂处理的护香效果,旨在优化设计葡萄酒的陈酿工艺。研究以户太8号桃红葡萄酒为试材,当葡萄酒发酵结束后分别添加适量葡聚糖、没食子酸、甘露糖蛋白和谷胱甘肽处理,而后定期采集酒样,对酒样香气通过仪器和感官进行分析。香气成分采用SPME-GC-MS定性定量分析,香气特征通过感官培训的品评小组量化品评。结果表明:户太8号桃红葡萄酒中共定量出33种香气物质,有9种成分的气味活性值(OAV)大于1,11种成分的OAV在0.1~1.0。贮藏期间,酒样中乙酸酯和中链脂肪酸乙酯含量在贮藏初期急剧下降而后趋于平稳,高级醇含量逐渐升高至平缓,脂肪酸、萜烯类和苯乙基类化合物的含量逐渐升高并在贮藏后期降低。贮藏1年后,葡聚糖处理的酒样中果香酯、苯乙基类以及己(烯)醇类化合物等香气物质含量明显高于其他处理组,而其他处理组之间差异不显著。感官分析也表明,葡聚糖处理组比其他处理组具有更好的温带水果、甜香、花香和小浆果香的香气特征。研究发现,在发酵结束后添加300mg/L葡聚糖对贮藏期户太8号桃红葡萄酒表现出较好的护香作用。     

大学生对食品添加剂风险认知现状及影响因素

目的：了解大学生对食品添加剂的认知状况和影响因素,为食品添加剂风险交流提供依据。方法：采用随机抽样方法,对北京大学学生进行自填式问卷调查。结果：北京大学学生对于食品添加剂有较高的风险认知和负性情绪。知识和企业风险控制等对于降低风险认知和负性情绪都有显著影响。但是,知识知晓和企业风险控制评价的情况均较差,71.4%的受访者将违法添加物三聚氰胺等视为食品添加剂,仅8.9%的受访者认为企业会按标准使用食品添加剂。结论：要促进食品添加剂的科学认知、降低负性情绪,应加强食品添加剂知识的科普宣教、并规范企业遵纪守法的行为。     

印刷适印剂在贴花纸中的应用

介绍了印刷适印剂在贴花纸中应用的实验过程和数据,结果表明:实验条件下,贴花纸抄造过程中加入适量印刷适印剂能够改善纸样的印刷适性。     

The consumer’s perception of artificial food additives: Influences on acceptance,risk and benefit perceptions

Food additives, such as food colours or sweeteners, play an important part in food supply. For a variety of reasons, some consumers might regard the use of food additives, especially artificial ones, with suspicion; food additives are considered unnatural, unhealthy or even a public health risk. The goal of this study was to investigate consumers’ perceptions and the most essential variables related to the acceptance of food additives. Two versions of a paper-and-pencil questionnaire, one investigating artificial food colours and the other investigating artificial sweeteners, were distributed to a large sample of Swiss German households. The final samples for artificial food colours and artificial sweeteners comprised 506 and 487 participants respectively. The questionnaires contained items on consumers’ acceptance, risk and benefit perception, trust in regulators, knowledge of regulation and their preference for natural products. The relationships between variables were investigated in a path model, which was constructed based on a review of previous literature. The path coefficients suggested that risk and benefit perceptions significantly influence the acceptance of the two selected food additives. The risk and benefit perceptions were influenced by consumers’ knowledge of regulation, their trust in regulators, and their preference for natural products. In the discussion, the study’s findings are examined in terms of their implications for further research and for the development of concrete communication materials.     

果胶酶处理造纸白水对薄页包装纸阳离子化学助剂使用效果影响的研究

研究白水中阴离子垃圾对PAE的增湿强效果、壳聚糖的增干、湿强效果、阳离子淀粉的增干强效果以及AKD的施胶效果的影响,并与使用果胶酶处理阴离子垃圾后阳离子助剂使用效果对比。结果表明：阴离子垃圾可显著降低阳离子添加剂的使用效果;白水经果胶酶处理后,阴离子垃圾对阳离子助剂的不利影响显著下降,阳离子助剂的效果得到明显增强。     

Plant‐oil‐based lubricants and hydraulic fluids

It is estimated that, at present, approximately 50% of all lubricants sold worldwide end up in the environment via total loss applications, volatility, spills or accidents. More than 95% of these materials are currently mineral oil based. In view of their high ecotoxicity and low biodegradability, mineral oil‐based lubricants constitute a considerable threat to the environment. In contrast, most lubricants and hydraulic fluids based on plant oils are rapidly and completely biodegradable and are of low ecotoxicity; moreover, lubricants based on plant oils display excellent tribological properties and generally have very high viscosity indices and flashpoints. However, in order to compete with mineral‐oil‐based products, some of their inherent disadvantages must be corrected, such as their sensitivity to hydrolysis and oxidative attack, and their behaviour at low temperatures. Various methods to improve the undesirable properties of native plant oils will be discussed. In parallel, government regulations that encourage or enforce the use of bio‐based fluids, at least in ecologically sensitive areas, will help to increase their market share. Using the numerous possibilities for selective breeding and/or chemical improvement of the double bond systems of natural fatty acids by increased R&D, the major obstacles regarding the use of plant‐based raw materials for the production of lubricant base fluids can be overcome and bio‐based fluids should expect a future with increasing market shares. Copyright © 2006 Society of Chemical Industry     

超高效液相色谱-串联质谱法检测多基质保健食品中27种非法添加降糖类化合物

目的 建立超高效液相色谱-三重四极杆质谱检测保健食品中27种降糖类非法添加化合物的方法。方法 4种不同基质保健品样品经甲醇超声提取后,采用Waters XBridge Amide色谱柱 (2.1 mm×100 mm, 3.5 μm),以5 mmol/L甲酸铵水溶液和5 mmol/L甲酸铵乙腈作为流动相进行梯度洗脱,分离苯乙双胍、二甲双胍、伏格列波糖、阿卡波糖、丁二胍共5种化合物;采用Waters CORTECS T3色谱柱 (2.1 mm×100 mm, 2.7 μm),以0.1%甲酸水溶液和乙腈作为流动相进行梯度洗脱,分离维达列汀、罗格列酮、西他列汀、吡格列酮等22种化合物;环格列酮采用电喷雾离子化负离子模式,其余26种化合物采用电喷雾离子化正离子模式,以多反应监测方式进行检测。结果 伏格列波糖、阿卡波糖、达格列净、卡格列净、曲格列酮、环格列酮6种化合物在250 ng/mL~12.5 μg/mL范围内线性关系良好,其余21种化合物在5~250 ng/mL范围内线性关系良好,线性相关系数r均大于0.99;27种化合物检出限(limit of detection, LOD)范围为1~1000 μg/kg;在低、中、高三水平加标,其回收率均在70%~120%范围内,相对标准偏差(relative standard deviation, RSD)为0.7%~10% (n=6)。结论 本方法快速、灵敏、高效、准确,适用范围广,可用于保健食品中降糖类化合物的高通量检测。