折光法检测食品添加剂乳酸的含量

目的 建立一种用折光法检测食品添加剂乳酸的含量的方法。方法 配置标准乳酸浓度梯度, 使用阿贝折射仪测得标准品的折光指数, 绘制出乳酸的标准曲线, 并测量样品的折光指数, 带入标准曲线计算样品中乳酸含量, 并将折光法计算得到的乳酸含量与国标法滴定值进行比较。结果 折光法线性方程为Y=9.2545X?12.3305, 相关系数r2为0.9999。折光法与滴定法的最大偏差为0.51, 折光法检测乳酸的相对标准偏差为0.1%(n=6)。结论 相比滴定法, 折光法取样量少, 操作简单、检测快速, 为乳酸含量的快速检测提供了一种新的检测方法。     

速冻水饺复合改良剂的研制

为提高速冻水饺的品质,通过单因素和正交试验,对几种食品添加剂对速冻水饺品质的影响进行研究。结果表明：乳酸钠和复合磷酸盐能显著提高产品的质量;添加剂的复配使用具有更好的效果,其最佳复合配方为：0．2％复合磷酸盐＋0．3％乳酸纳＋0．4％瓜尔豆胶＋0．1％黄原胶。添加复合品质改良剂的水饺,经过速冻和蒸煮后,产品完整性良好,煮后不混汤。     

超高效液相色谱-四极杆/飞行时间质谱筛查水果罐头中37种食品添加剂

建立了超高效液相色谱-四极杆飞行时间质谱筛查水果罐头中37种食品添加剂的方法。试样用乙腈-水提取,以乙腈-乙酸铵溶液为流动相,在Acquity UPLC BEH C_(18)色谱柱上进行分离,电喷雾电离源负离子模式下采用全信息串联质谱信息采集的模式检测,通过各化合物的分子离子和特征碎片离子结合保留时间定性,外标法定量。结果表明,方法定量限为0.02~0.5 mg/kg,在0.5~50μg/m L内线性关系良好(r≥0.99),所有添加剂的回收率为79.5%~103.5%。该方法快速、灵敏、准确,适用于罐头中37种食品添加剂的快速筛查。     

JECFA对食品添加剂的安全性评价

食品添加剂的安全性问题是食品工业普遍关注并亟待解决的问题,JECFA是国际食品添加剂与污染物安全评价的权威机构。介绍了JECFA对食品添加剂的安全性评价概况及评价结果。总结了近几年JECFA对几种食品添加剂的评价结果,主要介绍了各种物质的ADI值,并对各种物质的功能类别做了说明。     

Comprehensive European dietary exposure model (CEDEM) for food additives

European methods for assessing dietary exposures to nutrients, additives and other substances in food are limited by the availability of detailed food consumption data for all member states. A proposed comprehensive European dietary exposure model (CEDEM) applies summary data published by the European Food Safety Authority (EFSA) in a deterministic model based on an algorithm from the EFSA intake method for food additives. The proposed approach can predict estimates of food additive exposure provided in previous EFSA scientific opinions that were based on the full European food consumption database.     

Testing guidelines for evaluation of the immunotoxic potential of direct food additives.

Immunotoxicity testing is a new addition to the safety assessment guidelines for direct food and color additives. The approaches and philosophy for this area of specialized testing are consistent with the case-by-case strategy applied in the regulatory approval process, which is based on structure-activity relationships, preexisting knowledge, and projected exposure estimates. Specialized testing such as immunotoxicity is not part of the basic testing requirements, but would be applied when indicators are positive. Concepts for immunotoxicity testing have evolved, in part, from research for evaluating various testing methods as well as specific study designs. This research, conducted over the last decade, has focused mainly on the rat as the rodent species of choice. The miniature swine was evaluated as a nonrodent model. Testing is defined by type 1 and type 2 tests, which differ in that type 1 tests are performed on the same animals used in the core study design. Sets of type 1 and type 2 tests, with reference to the indicators, define various testing levels. Retrospective testing, expansion of basic testing (such as histopathology and serum chemistry profiles), and alternative study designs, which include satellite groups for evaluation of the functional capacity of the immune system, can be considered in the evaluation of immunotoxic potential.     

Safety evaluation of substances consumed as technical ingredients (food additives)

The different types of acceptable daily intakes (ADIs) are described as used by the FAO/WHO Expert Committee on Food Additives (JECFA) and the EEC Scientific Committee for Food (SCF). The allocation is discussed of a full ADI or a temporary ADI, and examples are given for the establishment (or withdrawal) of these ADIs. The flavours cinnamyl anthranillate and the solvent 2-nitropropane (both withdrawn), the sweeteners cyclamate and saccharin and the antioxidant BHA (all three changed) but not abolished. For BHA and saccharin the ADI was retained by both committees in spite of some evidence of carcinogenicity to experimental animals. ADI--'not specified' is specially discussed and it is recommended that numerical ADIs are used whenever possible. With an ADI--'not specified' it should be stated which use (and intake) levels are toxicologically acceptable. Some compounds evaluated by the two committees are discussed, e.g. the colours: Allura red AC, erythrosine, canthaxanthin and the caramels; three anti-oxidants: BHA, BHT and the gallates; the sweeteners: polyols, aspartame, saccharin and cyclamates. Four recommendations are made: (1) a numerical basis be given for the levels allocated an ADI--'not specified' or 'acceptable'; (2) lowering of the conventional safety factor be considered when the effects found are trivial--higher safety factors be considered when the toxic effects are serious or even irreversible; (3) ADIs should, whenever possible, be based on a combination of human and animal data; (4) ADIs might be allocated to compounds indicating animal carcinogenicity, if the compound is non-genotoxic, the mechanism clearly secondary and/or species-specific.     

锌粒还原法快速测定食品中的硝酸盐

目的：建立食品中硝酸盐的快速测定方法。方法：用锌粒作还原剂，在银离子催化下将食品中的硝酸盐还原成亚硝酸盐，然后按亚硝酸盐的测定方法测定。结果：该方法的相对标准差低于5％，平均回收率94．0％。结论：运用该方法能对食品中的硝酸盐进行准确而快速的测定。