分子光谱技术结合深度学习模型识别食用植物油种类

为实现对食用植物油的快速无损识别，采用衰减全反射-傅里叶变换红外光谱获取10种食用植物油样本的340份谱图数据，经过预处理消除光谱数据中的噪声与背景干扰，通过主成分分析降维特征提取3个主成分，在此基础上构建KNN模型与基于SSA算法优化的BP神经网络模型，对植物油种类进行识别并对识别效果进行比较。结果表明：KNN模型的识别准确率可达97.7%;基于SSA算法优化的BP神经网络分类效果最佳，识别准确率达100%,而传统BP神经网络模型识别准确率仅为87.6%。综上，建立的分子光谱技术结合深度学习模型识别食用植物油种类的新方法，实现了对食用植物油种类的准确识别。     

基于嗅觉可视化技术的食用植物油分类识别

为实现山茶油与3种常见食用植物油(菜籽油、大豆油和玉米油)的区分,制备可视化传感器阵列,采用嗅觉可视化技术对4种不同种类的食用植物油进行分类识别。采用主成分分析(PCA)对4种油样的特征数据进行降维,然后将降维后的数据导入K近邻(KNN)、极限学习机(ELM)、支持向量机(SVM) 3种分类模型中进行模型参数优化,对比了3种分类模型的分类结果。结果表明：建立的SVM分类模型性能最优,当输入主成分向量数为7、c=1.741 1、g=4.549 8时,SVM分类模型的测试集分类识别准确率为95.8%,五折交叉验证准确率为89.6%。制得的可视化传感器阵列可以实现4种食用植物油的分类识别,嗅觉可视化技术用于食用植物油检测是可行的。     

红外光谱快速识别食用植物油种类的研究

为实现食用植物油种类的快速无损识别,为公安实战中打击“食药环”犯罪提供参考,借助衰减全反射-傅里叶变换红外光谱技术对不同类别、品牌食用植物油进行了多层次分类识别工作。采用标准正态变换(SNV)和一阶导数预处理消除基线和其他背景干扰,使得重叠峰发生分离,从而提高检测的分辨率和灵敏度,利用竞争性自适应重加权算法(CARS)提取特征波长,结合基于布谷鸟搜索算法优化的极限学习机(CS-ELM)模型对不同种类和品牌的食用植物油进行分类识别,同时对比随机森林模型与CARS-CS-ELM融合模型在食用植物油快速分类检测方面的准确率。结果表明,基于CARS-CS-ELM融合模型对3类植物油样本总体进行分类,其分类准确率达到85.19%,其中小磨香油、花生油、玉米油样本训练集的品牌分类准确率依次为92.5%、100%、96.7%,测试集品牌分类准确率均为100%,而随机森林模型的9个品牌食用植物油分类准确率仅为80%。综上,CARS-CS-ELM融合模型对食用植物油快速分类识别效果较好,可为食用植物油的无损快速检验提供一定的参考与借鉴。     

基于滤波器的动植物油光谱信号预处理方法比较及识别分类

为实现对动植物油的快速无损检验，探究滤波器在提高光谱分析模型区分能力方面的可行性，该研究借助衰减全反射-表面增强红外吸收光谱技术，采集了动物油(159份)和植物油(188份)共计347份样本的光谱信息数据，构建了Fisher判别分析、支持向量机和决策树3种分类模型。比较了希尔伯特变换、有限长单位脉冲响应滤波器、无限长冲激响应滤波器、快速傅里叶变换和小波变换5种滤波器对3种分类模型精度的影响，同时考察了滤波器窗函数(矩形窗、汉宁窗、海明窗、布莱克曼窗)、小波基函数(Morlet、Dgauss、Mexhat、Haar、Daubechies、Biorthogonal)、滤波方式(低通、高通、带通、带阻)在动植物油样本区分效果方面的差异性。结果发现，滤波器能显著提升光谱分析模型的准确性，低通和带阻滤波方式，矩形窗和布莱克曼窗函数能有效提升模型对样本的区分能力，相较于其他2种算法，支持向量机对各样本的识别区分能力最好。基于FIR低通/带阻滤波器处理后构建的SVM模型(RBF核函数)可作为动植物油样本识别的最佳模型，其对347份样本实现了100%的“类别-品牌”的两级准确区分。综上，滤波器可有效提...     

基于连续分类策略的动物油红外光谱无损识别

为实现对市面上常见以及实际案件中出现的动物油样本进行快速无损识别，借助光谱分析技术和机器学习算法，基于连续分类策略，对不同动物油样本在种类及品牌/来源地方面进行区分和认定。收集了247份动物油样本(鸡油、牛油、鹅油、猪油、羊油、鸭油),对其进行红外光谱扫描，采用自动基线校正和峰面积归一化消除样本基线漂移和量纲不一致情况；再分别采用Savitzky-Golay平滑、二项式平滑、邻域平均法、FFT滤波、一阶导数和二阶导数对红外光谱进行预处理，比较了6种预处理方法在降噪方面的差异性，同时构建不同预处理方法下的随机森林、贝叶斯网络以及最小二乘支持向量机3种分类模型，开展各样本“种类—品牌/来源地”的连续分类工作。结果表明，相较于未预处理模型，经过预处理后，模型的识别能力均有提升，其中采用FFT滤波预处理结合随机森林模型可较好区分6种动物油，其对6种动物油样本品牌/来源地的识别准确率由高到低依次为鸡油、牛油、鹅油、猪油、羊油、鸭油；对实际案件中2份检材进行验证性分析，结果与实际情况相符合。红外光谱结合机器学习算法可应用于基于连续分类策略的动物油的快速无损识别。     

融合高光谱和图像深度特征的腊肉分类与检索算法研究

本文以腊肉为实验对象,建立一种融合光谱曲线特征和图像特征的肉类食品分类与检索方法,利用10个3×3的卷积层、3个5×5的卷积层、5个5×5的池化层和2个全连层的CNN模型对高光谱图像进行特征提取,并以交叉熵作为优化目标,同时利用多元散射校正和主成分分析方法(Principal Component Analysis,PCA)对光谱特征进行预处理和特征提取,然后将两种特征进行融合,并将融合特征利用支持向量机(Support Vector Machine,SVM)进行分类。结果表明,直接使用CNN训练好的模型对高光谱图像进行特征提取,利用SVM作为分类器,分类的准确率只有75.6%,融合光谱曲线特征后用SVM进行分类,准确率可达99.2%。此外,本文还计算了被检索样本和标准等级样本特征向量的欧氏距离,完成了腊肉新鲜度等级的检索任务,显示了该方法的可行性和有效性。     

电子舌对不同食用植物油区分识别研究

采用法国Alpha M.O.S公司生产的电势型味觉电子舌系统对20种不同品种、不同原料产地的食用植物油进行区分与识别,并对传感器阵列采集的食用植物油响应数据进行主成分分析和判别因子分析.结果表明:传感器阵列的选择与剔除由不同食用植物油样品和不同传感器响应能力决定,主成分分析和判别因子分析2种方法均能较好地对食用植物油样品进行分类识别,分析结果显示判别因子分析优于主成分分析.电子舌作为一种新型的现代检测技术在油脂品质定性定量检测与分析方面具有巨大的应用潜力.     

基于分类特征提取和深度学习的牛肉品质识别

目的：降低数据差异性和光谱特征冗余度对牛肉品质识别的影响。方法：提出一种基于分类特征提取和深度学习的牛肉品质识别方法,采用改进的DPeak算法对光谱数据进行自适应聚类分析,实现对数据的差异性分析。定义牛肉光谱特征提取目标函数,采用离散狮群算法进行求解,提取每个分类的最佳光谱特征子集,最大限度降低特征冗余度。运用改进狮群算法(ILSO)对每个分类对应的支持向量机(SVM)模型参数进行优化,提出融合分类特征提取和ILSO优化SVM的牛肉品质识别模型,完成对牛肉品质的分类识别。结果：相比于SSA-SVM、PCA-SVM识别模型,该模型识别精度提高了约12.3%~14.5%。结论：基于分类特征提取和深度学习的牛肉品质识别模型能够提高牛肉品质识别精度。     

拉曼光谱结合模式识别方法鉴别大米种类

为实现大米种类准确、快速的鉴别,选购72份大米样品,粉碎,采集粒度为100-140目米粉的拉曼光谱,对谱图数据进行去噪、归一化和特征提取后,综合运用主成分分析（PCA）、层次聚类分析（HCA）和支持向量机（SVM）三种方法对粳米、籼米和糯米进行聚类与模式识别研究。三种大米经PCA分析可直观地归为三簇,籼米和糯米可被区分开,但粳米与糯米、粳米与籼米不能区分。HCA结果表明粳米与籼米较难区分,糯米与其它两种米有较大差异,三种大米经HCA聚类分析准确率为81.94%。而采用SVM判别方法经10次运行后的平均识别率达98.86%。实验证明：拉曼光谱法结合支持向量机用于大米种类的分类与识别简单快速,在分析数据相对复杂的情况下,可快速建立分类模型并实现大米种类间的鉴定与识别。     

基于傅里叶近红外光谱和电子鼻技术的苹果霉心病无损检测

为研究傅里叶近红外光谱技术(Fourier transform near infrared spectroscopy,FT-NIRS)和电子鼻技术分别结合化学计量学方法对苹果霉心病的判别效果,以“红富士”霉心病苹果和健康苹果为试材,利用近红外光谱技术,基于主成分分析建立Fisher判别和多层感知器(multi-layer perceptron,MLP)神经网络模型;同时利用电子鼻技术分别结合Fisher判别、MLP神经网络和径向基函数神经网络3种化学计量学的方法建立判别模型。根据建模集和验证集的预测准确率综合考虑,基于主成分分析建立的MLP神经网络模型和电子鼻结合MLP神经网络模型对苹果霉心病的判别效果最好,验证集中的正确判别率分别达到87.7%和86.2%。说明电子鼻和近红外光谱技术均可以较好地判别苹果霉心病。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the