卷烟降焦减害技术研究进展

回顾了近年来国内外卷烟降焦减害技术的科研动态与科研新成果,重点介绍了生物材料、纳米材料、分子筛、低温催化剂以及低危害烟叶调制技术、低侧流烟气技术等在卷烟降焦减害方面的应用研究进展。介绍了新型特殊功能滤嘴、新型滤嘴材料和多种滤嘴及卷烟添加剂在卷烟降焦减害上的应用现状,同时,还简要介绍了近期开发出的可有效降焦减害的几种烟草加工工艺与烟草处理技术。  

皮革中多环芳烃(PAHs)测定方法

介绍了皮革中多环芳烃的测定方法,样品用正己烷经加速溶剂萃取、凝胶渗透色谱净化、自动定量浓缩后,用气相色谱质谱联用仪测定。方法检测低限为0.20μg/mL,实验室内相对标准偏差小于5%,回收率除萘以外均大于80%。  

Polycyclic aromatic hydrocarbons in meat smoked with different types of wood

The influence of the wood used for the smoking of meat on the formation of polycyclic aromatic hydrocarbons (PAH) has been studied. Ten types of wood and charcoal were used for preparation of smoked meat samples. The analytical sample preparation method implied extraction of PAH with cyclohexane, liquid–liquid extraction with N,N-dimethylformamide/water, back extraction with cyclohexane, followed by clean-up on silica solid phase extraction (SPE) column and quantification by gas chromatography–mass spectrometry. It was found that the type of wood has a significant influence on the amount of PAH in smoked meat. The samples smoked with apple-tree and alder contained the smallest PAH concentrations. The samples smoked with spruce had the highest concentrations of PAH. The difference in content of benzo[a]pyrene (from 6.04 till 35.07 μg/kg) and total PAH (from 47.94 till 470.91 μg/kg) indicates that choice of wood for smoking is one of the critical parameter to be controlled in order to diminish the contamination of food products.  

食品中多环芳烃的提取、纯化、以及检测方法的研究进展

对食品中多环芳烃(PAHs)的提取、纯化机理和检测方法进行了概述,侧重介绍了样品提取、纯化和分离过程中影响PAHs回收率的各种因素。  

Nucleotide sequences and characterization of genes encoding naphthalene upper pathway of pseudomonas aeruginosa PaK1 and Pseudomonas putida OUS82

A 12,808-nucleotide containing DNA fragment cloned from naphthalene-utilizing (Nah+) Pseudomonas aeruginosa PaK1 was analyzed and compared with the genes (pah(OUS)) of a 14,462-nucleotide DNA fragment from Pseudomonas putida OUS82. The DNA sequence analyses demonstrated that the naphthalene upper-pathway genes and their deduced enzymes were very similar between the two bacteria: nucleotide similarities, 83-93%; amino acid similarities, 79-95%. These genes were also similar to those of the nah operon of plasmid NAH7; in particular, the OUS82 genes were similar to the nah genes, whereas the PaK1 genes were almost identical to the dox genes of Pseudomonas sp. C18. A region homologous with the 84-bp repeated sequence that Eaton (J. Bacteriol., 176, 7757-7762, 1994) has found at a site upstream of he nah operon was found only in a region downstream of the pah(PaK) gene cluster in PaK1 and on both sides of the pah(OUS) gene cluster in OUS82. A PaK1 gene, corresponding to an unknown gene (nahQ) in the nah operon, is located between the 1,2-dihydroxynaphthalene dioxygenase gene and the trans-o-hydroxybenzylindenepyruvate (tHBP A) hydratase-aldolase gene (nahE), and was suggested to be involved in the conversion of naphthalene to salicylate. Just downstream of the pah(PaK) gene cluster, a portion of a region was identical to one-third of the transposase gene (tnpA) in a phenol-catabolic plasmid pEST1226.  

食用油脂中多环芳烃检测的前处理技术研究进展

多环芳烃(PAHs)是由两环或多环组成的有机化合物,具有基因毒性和致癌性.由于PAHs的亲脂性,食用油脂是最重要的PAHs来源.油脂基体复杂,所含干扰物多,常规分析方法检测其中的PAHs难以获得令人满意的结果,因此需要采用适当的样品前处理技术以达到分析检测要求.综述了近年来有关油脂中PAHs的前处理技术,重点针对这些技术的特点进行了比较和归纳,并对油脂中PAHs前处理技术的发展进行了展望.提出在线样品前处理技术是此领域的发展方向.  

Polycyclic aromatic hydrocarbons (PAHs) in different types of smoked meat products from Serbia

The contents of the16 EU priority PAHs in six different meat products from Serbia (beef ham, pork ham, bacon without skin, bacon with skin, cajna sausage and sremska sausage) were examined during the process of smoking. All these meat products from meat industry Zlatiborac, Mačkat, Serbia presented in this study, have not previously been analysed concerning to their contents of PAH compounds. Determination and quantification of PAHs in meat products were performed by a Fast GC/HRMS method. The maximum level for benzo[a]pyrene (BaP) of 5 μg/kg in smoked meat products was not exceeded in any samples. BaP comprises in general 4.6% of the total sum of the 16 EU priority PAHs and 15.2% of the total sum of the 12 IARC PAH compounds. The suitability of BaP as a marker both for 16 EU priority PAHs and 12 IARC probably and possibly carcinogenic PAHs was checked by applying correlation analysis.  

Meat and cancer

An increasing literature associates high intake of meat, especially red meat and processed meat with an increased risk of cancers, especially colorectal cancer. There is evidence that this risk may not be a function of meat per se, but may reflect high-fat intake, and/or carcinogens generated through various cooking and processing methods. The cancer risk may be modulated by certain genotypes. Cancers associated with high meat consumption may be reduced by the addition of anticarcinogens in the diet, especially at the same time as meat preparation or meat consumption, or modification of food preparation methods. Meat contains potential anticarcinogens, including omega-3 polyunsaturated fatty acids, and conjugated linoleic acid (CLA). Red meat, in particular, is an important source of micronutrients with anticancer properties, including selenium, vitamin B6 and B12, and vitamin D. Adjusting the balance between meat and other dietary components may be critical to protecting against potential cancer risks.  

Determination of benzo[a]pyrene in some Spanish commercial smoked products by HPLC-FL

In order to investigate the levels of the potently carcinogenic benzo[a]pyrene (BP), 31 samples of smoke foods were analysed. The samples tested included five samples of meat products, three samples of cheese and 22 samples of fish. A liquid chromatographic method was developed using a fluorescence detector. BP was found in 74% of the samples analysed. The levels varied from not detected to 2.46 mug/kg. Only one sample showed a BP level above 1 mug/kg, the maximum level that the EU intends to set for smoked foods.  

Determination of polycyclic aromatic hydrocarbons in smoked fishery products from different smoking kilns

The levels of 13 polycyclic aromatic hydrocarbons (PAH) were determined by an HPLC method with fluorescence and UV detection and by a GC/MS technique in smoked fishery products from modern smoking kilns with external smoke generation and from traditional smoking kilns. The average benzo(a)pyrene (BaP) concentration of all 35 samples from commercial smoking kilns with external smoke generation was 0.1 g/kg (wet weight) and the sum of the carcinogenic compounds determined in the study, i.e. benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenz(a,h)anthracene and indeno(1,2,3-c,d)pyrene did not exceed 4.5 g/kg (wet weight). The BaP levels of the 27 smoked fish samples from traditional kilns ranged from 0.2 g/kg to 4.1 g/kg, with a mean value of 1.2 g BaP/kg. The average concentration of the sum of the carcinogenic compounds was 9.0 g/kg. Large variations were found in the content of the non-carcinogenic PAHs phenanthrene, anthracene, fluoranthene and pyrene in all samples from both types of smoking kilns.