动物性食品中莱克多巴胺检测方法研究进展

莱克多巴胺作为激素类添加剂,对动物机体产生副作用,同时影响消费者的健康.近年我国进出境口岸屡次在进口动物性食品中检出莱克多巴胺.本文对近几年来动物性食品中莱克多巴胺的检测方法新进展和新兴技术做了大量调查和整理,旨在为出入境口岸动物性食品中莱克多巴胺的检测提供一定的参考,为进出口动物性食品的安全控制提供理论依据.     

化学发光免疫分析法在新疆地产动物源性食品中硝基呋喃代谢物检测的应用

目的探讨化学发光免疫分析法(chemiluminescence immunoassay,CLEIA)检测新疆地产动物源性食品中呋喃唑酮(furazolidone,AOZ)、呋喃它酮(furaltadone,AMOZ)、呋喃西林(nitrofurazone,SEM)、呋喃妥因(nitrofurantoin, AHD)的效果。方法运用化学发光免疫分析法检测采集自新疆不同地区的150份动物源性食品的AOZ、AMOZ、SEM和AHD;采用液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)进行结果验证。结果 CLEIA检测发现150份样品中AOZ检出率最高,为2.00%; AMOZ的检出率次之1.33%; SEM、AHD均未检出。鸡肉样品的硝基呋喃类药物残留检出率最高,为5.56%;牛肉和蛋类检出率分别为2.44%和3.57%;羊肉、猪肉和蜂蜜中未检出。UPLC-MS/MS检测结果与CLEIA检测结果一致。结论 CLEIA可用于动物源性食品的硝基呋喃代谢物的初筛检测。     

Determination of the overall migration from silicone baking moulds into simulants and food using 1H-NMR techniques

Different silicone baking moulds (37 samples) were characterized with respect to potential migrating substances using ¹H-NMR, RP-HPLC–UV/ELSD and GC techniques. In all cases cyclic organosiloxane oligomers with the formula [Si(CH₃)₂–O] _n were identified (n = 6 … 50). Additionally, linear, partly hydroxyl-terminated organosiloxanes HO–[Si(CH₃)₂–O] _n –H (n = 7 … 20) were found in 13 samples. No substances other than siloxanes could be detected, meaning the migrants mainly consist of organopolysiloxanes. Based on this knowledge, a ¹H-NMR quantification method for siloxanes was established for the analysis of both simulants and foodstuffs. Validation of the ¹H-NMR method gave suitable performance characteristics: limit of detection 8.7 mg kg^–1 oil, coefficient of variation 7.8% (at a level of 1.0 mg kg^–1 food). Migration studies were carried out with simulants (olive oil, isooctane, ethanol (95%), Tenax) as well as preparation of different cakes. From the 1st to 10th experiment, siloxane migration into cakes only slightly decreased, with a significant dependence on fat content. Migration never exceeded a level of 21 mg kg^–1 (3 mg dm^–2) and was, therefore, well below the overall migration limit of 60 mg kg^–1 (10 mg dm^–2). However, migration behaviour into simulants differed completely from these results.     

大米中环已烯酮类除草剂残留量的测定

建立了大米中环己烯酮类除草剂残留量同时测定的液相色谱-质谱/质谱法。试样中残留的环己烯酮类除草剂用酸性乙腈高速匀浆提取,提取液经N-丙基乙二胺（PSA）、十八烷基硅烷（ODS）和石墨化炭黑净化,用液相色谱-质谱／质谱仪检测和确证,外标法定量。环己烯酮类除草剂的浓度在0．0025～0．1000μg·mL^-1范围内时,线性关系良好,8种环己烯酮类除草剂的相关系数为0．9947～0．9992。在0．005～0．050mg·kg^-1浓度范围内,样品平均加标回收率在73．2％～107．0％之间,相对标准偏差为5．14％～10．15％。8种环己烯酮类除草剂的最低检出限均为0．005mg·kg^-1。     

高温加热食品丙烯酰胺问题的探讨

丙烯酰胺对人和动物是一种有效累积性神经毒物，近年来研究发现在高温加热食品中有丙烯酰胺产生，本文介绍了高温加热食品中丙烯酰胺的形成机理、影响其形成的各种因素以及测定其含量的各种方法，最后提出了降低丙烯酰胺的一些措施．     

Relationship between physicochemical properties and maximum residue levels and tolerances of crop-protection products for crops set by the USA, European Union and Codex

Residues on foodstuffs resulting from the use of crop-protection products are a function of many factors, e.g. environmental conditions, dissipation and application rate, some of which are linked to the physicochemical properties of the active ingredients. Residue limits (maximum residue levels (MRLs) and tolerances) of fungicides, herbicides and insecticides set by different regulatory authorities are compared, and the relationship between physicochemical properties of the active ingredients and residue limits are explored. This was carried out using simple summary statistics and artificial neural networks. US tolerances tended to be higher than European Union MRLs. Generally, fungicides had the highest residue limits followed by insecticides and herbicides. Physicochemical properties (e.g. aromatic proportion, non-carbon proportion and water solubility) and crop type explained up to 50% of the variation in residue limits. This suggests that physicochemical properties of the active ingredients may control important aspects of the processes leading to residues.     

Emulsifying properties of protein–pectin complexes and their use in oil-containing foodstuffs

The emulsifying properties of proteins have been well studied as they are important for the preparation of creams, mayonnaises and other oil/fat-containing foodstuffs. The emulsifying action of a protein is not always sufficient to obtain stable emulsions of good quality. The use of chemical stabilisers in the food industry is not desirable. One of the best ways to improve the quality of emulsions and to produce emulsions with high nutritive value is to use protein-polysaccharide complexes as emulsifiers. Varying the protein-polysaccharide ratio in the complex, and also the kind of the polymers, would vary the quality and the nutritional value of the foodstuff. Four non-conventional protein preparations were tested as emulsifiers and their emulsifying properties were improved by the addition of pectin. This makes it possible to create new foodstuffs with low oil content and high nutritional value.     

Supramolecular solvent-based microextraction of Sudan dyes in chilli-containing foodstuffs prior to their liquid chromatography-photodiode array determination

A supramolecular solvent made up of reverse micelles of decanoic acid was proposed for the simple and rapid extraction of Sudan I, II, III and IV from chilli-containing foodstuffs. The procedure involved the extraction of minute quantities (0.5–1 g) of homogenised food sample with an aqueous solution containing 10% THF and 200 mg of decanoic acid, conditions under which the supramolecular solvent (around 330 μL) formed in situ and instantaneously. The overall sample treatment took about 30 min and several samples could be simultaneously treated using conventional lab equipment. No clean-up or solvent evaporation were required before determination of Sudan dyes by liquid chromatography and photometric detection. Extractions were independent of salt addition (up to 1 M), the temperature (up to 60 °C) and the pH (below 4) rendering the method robust. The detection limits of the method were 4.2, 2.7, 6.5 and 7.4 μg kg⁻¹ for Sudan I, II, III and IV, respectively. Recoveries obtained by applying this approach to the analysis of six chilli-containing sauces fortified with Sudan dyes at the μg kg⁻¹ level were in the interval 86–108% with relative standard deviations between 2% and 7%.     

Furan and Methylfurans in Foods: An Update on Occurrence,Mitigation, and Risk Assessment

The acceptance of many foods is related to traditional cooking practices, which create taste and texture and are important to digestibility, preservation, and the reduction of foodborne illnesses. A wide range of compounds are formed during the cooking of foods, a number of these have been shown to lead to adverse effects in classical toxicological models and are known as food processing contaminants (FPC). It is essential that the presence and effects of such compounds alone and in combination within the diet are understood such that proportionate risk management measures can be developed, while taking a holistic view across the whole value chain. Furan and alkylfurans (principally 2‐ and 3‐methylfuran) are highly volatile FPC, which are formed in a wide range of foods at low amounts. The focus of research to‐date has been on those foods, which have been identified to be most consequential in terms of being sources of exposure, namely jarred and canned foods for infants and young children (meals and drinks) and coffee (roast and ground, soluble). This report presents (i) new industry data on the occurrence of furan and methylfurans in selected food categories following previous coffee studies, (ii) the most salient parameters that impact furan formation, and (iii) aspects of importance for the risk assessment.     

膜芯片技术对牛、羊、牦牛、驴肉源食品的掺伪鉴别

采用膜芯片技术,通过对牛、羊、驴、牦牛、鸡、鸭、兔、貂、狐、鼠、猪11 种目标物种的检测,实现对牛、羊、驴、牦牛物种的掺伪鉴别。结果表明：该方法具有良好的特异性和适用性,检测灵敏度和掺伪灵敏度均可达到0.1%,能快速、准确地同时鉴别牛、羊、驴、牦牛、鸡、鸭、兔、貂、狐、鼠、猪11 种动物源性成分,可满足肉类食品样品中对牛、羊、牦牛、驴等掺伪鉴别的检验需求。