冷鲜羊肉品质的高光谱成像无损检测

利用400~1000 nm可见近红外高光谱成像系统对冷鲜羊肉蛋白质含量、嫩度、p H进行无损检测研究。采集冷鲜羊肉表面的高光谱散射图像,提取样本感兴趣区域的反射光谱曲线获得原始数据。先对原始光谱预处理并建立偏最小二乘回归(PLSR)模型,优选最佳预处理方法,后采用正自适应加权算法(CARS)和连续投影算法(SPA)提取特征波长,建立不同特征波长下各品质参数的PLSR预测模型。结果表明:利用原始光谱建立的冷鲜羊肉蛋白质、嫩度和p H的PLSR模型均优于经过光谱预处理所建PLSR模型;在不同波长下建立预测模型,OS-PLSR光谱模型对冷鲜羊肉蛋白质含量预测效果最佳,Rp=0.869,RMSEP=0.097;建立的SPA-PLSR光谱预测模型对p H预测效果理想,Rp=0.958,RMSEP=0.067;CARS-PLSR光谱预测模型对嫩度的预测能力较高,Rp=0.862,RMSEP=0.706。研究表明:利用可见近红外高光谱技术对冷鲜羊肉品质进行快速无损检测是可行的。     

NIR高光谱成像技术检测冷鲜羊肉嫩度

利用900~1700 nm近红外高光谱成像系统对冷鲜羊肉嫩度进行快速无损检测研究。采集冷鲜羊肉(1~8 d)表面的高光谱散射图像,提取样本感兴趣区域反射光谱曲线并用剪切力值表征冷鲜羊肉的标准嫩度。以原始光谱、特征区域光谱和Savitzky-Golay卷积平滑预处理光谱建立冷鲜羊肉嫩度的偏最小二乘回归(PLSR)模型,预处理的特征区域光谱建立的模型效果更优。结果表明:特征区域光谱可有效替代全波段光谱,经过S-G卷积平滑预处理后,模型预测效果最佳,预测相关系数(Rp)和均方根误差(RMSEP)分别为0.773和1.060。研究表明:利用近红外高光谱成像技术结合偏最小二乘回归法对冷鲜羊肉嫩度的快速无损检测是可行的。     

基于高光谱技术的羊肉含水率无损检测

利用高光谱成像系统(1000~2500 nm)对羊肉含水率进行无损检测研究。对108个羊肉样本进行光谱信息采集,通过标准正态变换法、归一化法、去趋势校正法、S-G卷积平滑法、导数法、多元散射校正法对原始光谱进行预处理,对全波段下的原始光谱和预处理后的光谱建立偏最小二乘回归(PLSR)模型,优选出的最佳预处理算法为去趋势校正法。原始数据经去趋势校正法预处理后,采用相关系数法选取特征波长,建立特征波长下羊肉含水率的 PLSR模型和逐步多元线性回归(SMLR)模型。结果表明,SMLR模型对含水率预测效果最好,校正集相关系数R_c为0.8597,标准误差SEC为0.0521;预测集相关系数R_p为0.8654,标准误差SEP为0.0387。研究表明,利用高光谱成像技术检测羊肉含水率是可行的。     

盐池滩羊肉脂肪含量的高光谱预测模型构建

本文利用可见-近红外高光谱成像技术预测冷鲜滩羊肉脂肪含量,优选最佳预测模型。测定90个滩羊背最长肌的脂肪含量并采集其光谱图像,对原始光谱进行不同种预处理后,构建了全波段下的偏最小二乘回归(PLSR)和主成分回归(PCR)的光谱预测模型。为减少模型运算次数,在预处理效果最优的全波段模型上采用连续投影算法(SPA)、应用竞争性自适应重加权(CARS)、变量组合集群分析(VCPA)和波长空间迭代收缩(IVISSA)方法提取特征波长,构建脂肪含量的光谱预测模型。结果表明:采用归一化(Normlize)预处理后光谱构建的PLSR全波段模型效果最好,校正集模型相关系数(Rc)达到0.921;采用多元散射校正(MSC)预处理后光谱构建的PCR全波段模型效果最好,其校正集模型相关系数(Rc)达到0.850;在4种提取特征波长过程中,IVISSA算法所提取特征波长的交互验证均方根误差(RMSECV)最低,为0.0072;Normlize-IVISSA-PLSR模型较其他3种算法所构建的PLSR模型效果最优,其校正集相关系数(Rc)和预测集相关系数(Rp)值分别为0.931和0.754,表明利用高光谱技术对盐池滩羊肉脂肪含量进行预测是可行的。研究成果为冷鲜滩羊肉品质在线光谱快速无损检测系统开发提供理论依据。     

宁夏赤霞珠葡萄水分含量的高光谱无损检测研究

利用可见近红外高光谱成像技术对宁夏赤霞珠葡萄含水量的无损检测进行了初步探讨。通过高光谱成像系统(400~1000 nm)采集了136幅赤霞珠葡萄图像,对原始光谱、平均平滑、高斯滤波、中值滤波、卷积平滑、归一化、多元散射校正、标准正态化、基线校准、去趋势化等预处理的偏最小二乘回归(PLSR)模型进行对比分析;采用主成分分析(PCA)、偏最小二乘回归(PLSR)、连续投影算法(SPA)、竞争性自适应重加权(CARS)方法选择特征波长,建立4种特征波长下的PLSR的葡萄含水量预测模型,优选CARS提取特征波长的方法。在此基础上,对比分析了全波段与特征波长下的MLR、PCR、PLSR的葡萄含水量预测模型。结果表明:采用多元散射校正(MSC)光谱建立的PLSR模型优于原始光谱和其他预处理光谱的PLSR模型;CARS提取特征波长建立的PLSR模型优于多元线性回归(MLR)、主成分回归(PCR)模型,预测集的相关系数(R)和预测均方根误差(RMSEP)分别为0.806、0.144。因此,利用可见近红外高光谱成像技术提取特征波长进行宁夏赤霞珠葡萄含水量的检测是可行的。     

基于VIS/NIR高光谱成像技术检测鸡肉嫩度

利用400~1000 nm可见近红外高光谱成像系统对鸡肉嫩度进行快速无损检测研究。采集鸡肉表面的高光谱散射图像,提取样本感兴趣区域反射光谱曲线并用剪切力值表征鸡肉的标准嫩度。以原始光谱和多元散射校正(MSC)预处理光谱数据建立鸡肉嫩度的偏最小二乘回归(PLSR)模型,预处理光谱建立的模型效果更优。基于MSC预处理,采用偏PLS权重系数法结合逐步回归法筛选出了4个特征波长。然后采用PLSR和多元线性回归(MLR)模型分别建立特征波长处光谱反射值和鸡肉嫩度关系的数学模型,优选最佳模型。结果显示:MLR模型预测效果较好,预测相关系数(RP)和均方根误差(RMSEP)分别为0.94和1.97。研究表明:利用可见近红外高光谱成像技术结合多元回归分析法对鸡肉嫩度的快速无损检测是可行的。     

基于高光谱成像技术的鸡蛋哈氏单位快速无损检测

本实验利用高光谱(900~1700 nm)成像技术结合化学统计学算法,对鸡蛋哈氏单位的无损检测进行研究。采集样品原始光谱信息,经S-G卷积平滑、MSC、SNV预处理后建立PLSR模型,优选最佳预处理方法;利用PLSR的加权β系数、遗传算法GA提取特征波长,分别建立PLSR、PCR模型,比较建模效果,优选最佳特征波长提取方法及建模方法。结果表明,预处理后建模效果并未提高,即以原始光谱作为建模对象,采用遗传算法提取特征波长后建立的PLSR模型效果最好,其R_C为0.8118,校正集均方根误差是2.9677,R_P为0.8203,预测集均方根误差是3.2762。因此,利用高光谱技术无损检测鸡蛋哈氏单位是可行的,同时为鸡蛋的新鲜度快速判别、分级分选提供理论依据。     

基于可见-近红外光谱预测灵武长枣脆度及模型优化

利用可见-近红外光谱对在4℃下冷藏24 h的灵武长枣脆度进行检测,并建立了最优模型。通过400~1 000 nm高光谱成像系统采集了112个长枣图像,对原始光谱与经SNV,MSC、S-G、1ST、2ND、SNV+1ST、MSC+1ST、SNV+2ND、MSC+2ND、SNV+S-G、MSC+S-G预处理后光谱的偏最小二乘回归(PLSR)模型进行了对比分析;采用主成分分析法(PCA)、连续投影算法(SPA)、竞争性自适应重加权法(CARS)提取特征波长,分别建立偏最小二乘回归(PLSR)和主成分回归(PCR)模型;将经预处理后的简化PLSR模型与全波段PLSR模型进行了对比分析。结果表明,采用标准归一化法(SNV)预处理后的PLSR模型优于原光谱及其他预处理方法;提取特征波长后建立的CARS-PLSR模型优于CARS-PCR模型和全波段PLSR模型,其相关系数(RP)和预测均方根误差(RMSEP)分别为0.919、1.121。这表明,基于可见-近红外光谱检测冷藏灵武长枣脆度是可行的,SNVCARS-PLSR模型最佳。     

高光谱成像技术对灵武长枣果皮强度的无损检测

利用高光谱技术对灵武长枣果皮强度检测进行研究,为灵武长枣外部品质无损检测提供科学方法。采集120个灵武长枣的400~1000 nm的高光谱图像,对光谱数据进行预处理;应用连续投影算法(SPA)、正自适应加权算法(CARS)和无信息变量消除法(UVE)对原始光谱数据提取特征波长;分别建立基于全光谱和特征波长的偏最小二乘回归(PLSR)和最小二乘支持向量机(LS-SVM)果皮强度预测模型。结果表明:采用标准正态变换(SNV)预处理算法效果最优,其PLSR模型的交叉验证相关系数(Rcv)为0.8207,交叉验证均方根误差(RMSECV)为9.9630;利用SPA、CARS和UVE法从全光谱的125个波长中分别选取出29个、31个和31个特征波长;而基于全光谱建立的LS-SVM模型效果最优,其预测相关系数(Rp)为0.9555,预测均方根误差(RMSEP)为3.8282;研究结果表明基于高光谱成像技术采集的灵武长枣漫反射光谱进行果皮强度无损检测具有可行性。     

冷鲜羊肉冷藏时间和水分含量的高光谱无损检测

利用可见-近红外高光谱成像技术对冷鲜羊肉的冷藏时间和水分含量进行无损检测。通过波长400～1 000 nm可见-近红外高光谱系统采集160 个羊肉样本光谱信息,优选主成分-14-线性判别法对原始光谱建立羊肉冷藏时间的判别模型,校正集对羊肉冷藏时间的判别率为99.17%,预测集为100%,模型可较好地判别羊肉的冷藏时间。其次,针对羊肉冷藏过程中水分含量的变化,优选最佳预处理方法并运用偏最小二乘回归（partial leastsquares regression,PLSR）法建立水分含量预测模型;结果表明,经过Savitzky-Golay卷积平滑预处理的PLSR模型对水分含量的建模效果最优,校正集和预测集相关系数分别为0.888和0.784,交互验证均方根误差为0.696。研究表明,采用可见-近红外高光谱成像技术对冷鲜羊肉冷藏时间的判别和冷藏过程中羊肉水分含量的快速预测是可行的。     

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.     

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.