紫苏子油中游离脂肪酸的动态分析

采用毛细管气相色谱的方法，以十五碳烷酸为内标，对紫苏子油中的五种游离脂肪酸：棕榈酸（Ｃ１６：０）、硬脂酸（Ｃ１８：０）、油酸（Ｃ１８：１）、亚油酸（Ｃ１８：２）、亚麻酸（Ｃ１８：３）进行分析，研究紫苏子油中五种游离脂肪酸在储藏期间的变化。此分析方法无需进行甲基化，直接分析游离脂肪酸的变化。研究中对每种脂肪酸都作了方法学研究，脂肪酸的线性范围在１４７～９２２ｐｐｍ之内，ｒ＾２值≤０．９９７。精密度≤     

气相色谱内标法测定水产饲料中的脂肪酸

建立以十三烷酸为内标物,气相色谱定量测定水产饲料中脂肪酸含量的方法。饲料样品中的油脂经酸热法提取、氢氧化钾-甲醇皂化、三氟化硼-甲醇甲酯化后衍生为相应的脂肪酸甲酯,以SPTM-2560毛细管柱分离,氢火焰离子化检测器测定,保留时间定性、峰面积内标法定量。结果表明,在所选择的色谱条件下,37种脂肪酸甲酯在65 min内获得较好的分离;9种主要脂肪酸加标回收率(n=6)为88.4%~107.5%,相对标准偏差为2.28%~4.79%,最低定量限(S/N=10)为2.0 mg/kg。该方法操作简便、快速、重复性好,适合批量水产饲料样品脂肪酸的定量测定。     

沙棘油特征指标的比较

采用气相色谱和化学滴定等手段,对不同产地的13个成品沙棘油及3份实验室提取的沙棘油（分籽油、全果油、果油）的酸值、过氧化值和特征指标（相对密度、折光指数、碘值、皂化值和脂肪酸组成）进行了测定,并进行比较分析。结果表明：16份沙棘油的酸值和过氧化值均符合相关标准要求;折光指数（n40）、相对密度（d2020）、碘值3个特征指标基本是按籽油、果油、全果油的顺序依次减小,皂化值则较为接近。沙棘籽油以亚油酸、亚麻酸、油酸、棕榈酸为主,不饱和脂肪酸含量为87.4%～88.1%;全果油以棕榈酸、棕榈油酸、油酸、亚油酸为主,不饱和脂肪酸含量为62.9%～70.4%;果油以亚油酸、油酸、棕榈酸为主,不饱和脂肪酸含量为81.9%～89.1%。沙棘油与3个进口橄榄油的脂肪酸组成基本相同,但在比例与含量上有很大差异。研究表明沙棘油是一种营养丰富、极具开发潜力的植物油。     

紫苏子油中游离脂肪酸的动态分析

采用毛细管气相色谱的方法,以十五碳烷酸为内标,对紫苏子油中的五种游离脂肪酸:棕榈酸(C16:0)、硬脂酸(C18:0)、油酸(C18:1)、亚油酸(C18:2)、亚麻酸(C18:3)进行分析,研究紫苏子油中五种游离脂肪酸在储藏期间的变化.此分析方法无需进行甲基化,直接分析游离脂肪酸的变化.研究中对每种脂肪酸都作了方法学研究,脂肪酸的线性范围在147～922 ppm之内,12值≤0.9997.精密度≤2.43%(n=5).最后用此法测定了不同储藏期间的样品,结果显示随储藏时间的延长,游离脂肪酸的总量增加,但各脂肪酸的变化情况不同.     

刺梨果中多元酸和高级脂肪酸的分析研究

目的分析刺梨果中多元酸和高级脂肪酸的组成。方法采用硫酸甲酯化处理刺梨果样品，用气相色谱-质谱联用（GC-MS）分析其多元酸和高级脂肪酸含量，用面积归一化法得出各有机酸的相对含量。结果共分离、鉴定22种酸性组分，占总峰面积的97．04％。结论刺梨果中高级脂肪酸和多元酸成分为：亚油酸（37．75％）、亚麻酸（19．51％）、油酸（15．15％）、棕榈酸（8．53％）、硬脂酸（4．12％）、枸橼酸（3．74％）和苹果酸（1．49％）等。     

气相色谱法分析酒花油的主要香气物质研究

建立了用气相色谱法测定酒花油中香叶烯、里那醇、石竹烯、法尼烯和律草烯含量的方法，并对4种酒花油样品进行了捡测：采用水蒸气回流提取法进行样品前处理．以十四烷作为内标物，色谱条件为：载气流速2.0ml/min、柱温为程序升温，100℃（Omin）-10℃/min-160℃（Omin）-30℃/min-210℃（5min），分流比25：1，进样量0．5℃L；分析时间短．12分钟内即可完成。内标法定量测得相对标准偏差为0．0120％～1．0707％，回收率在95．18％～102．25％之间，具有操作简便快捷、精密度好、准确度高的特点。检测结果表明，不同品种酒花油样品在主要香气物质上有较大差异，可以据此对酒花油及相应酒花的品质进行监控。     

薏米中营养成分的分析

采用索氏提取法对薏米中脂肪酸进行了提取并进行了甲酯化处理，以气相色谱-质谱联用仪进行了分析，共分离鉴定出12种脂肪酸，共占薏米中脂肪酸总量的95．66％。其中主要成分为：十六酸（棕榈酸）13．05％，9，12-十八碳二烯酸（亚油酸）35．75％，9-十八碳烯酸（油酸）39．85％。     

气相色谱法测定配方奶粉中的脂肪酸和反式脂肪酸

建立同时测定配方奶粉中脂肪酸和反式脂肪酸的气相色谱分析方法。样品中的脂肪酸和反式脂肪酸经乙酰氯-甲醇甲酯化处理后,用气相色谱仪测定,采用HP-88色谱柱分离定性,以十一碳酸甘油三酯为内标进行定量。结果表明:顺-反异构体脂肪酸分离效果较好,脂肪酸和反式脂肪酸的回收率在97.2%～104.6%之间,相对标准偏差小于3.5%,检出限为5μg/g。     

绿豆胚芽中脂肪酸组成和维生素E的分析

利用气相色谱对绿豆胚芽中脂肪酸组成进行了测定,结果表明绿豆胚芽油中脂肪酸主要由棕榈酸和不饱和酸组成,其中棕榈酸占２５．１４％、油酸占９．７４％、亚油酸占４２．２２％、亚麻酸占１６．９７％,与一般食用油脂相比较,绿豆胚芽油中亚麻酸含量明显高于常用油脂的亚麻酸含量。同时利用高效液相色谱法测定了ＶＥ的含量,流动相选用甲醇∶水（９８∶２,Ｖ／Ｖ）,流速０．６ｍｌ／ｍｉｎ,检测波长２９２ｎｍ,在ＺｏｒｂａｘＣ１８柱上测定了ＶＥ的含量,ＶＥ的平均含量为２３１ｍｇ／１００ｇ胚芽油,ＶＥ的回收率为９２．００％～１０２．００％,相对标准偏差为４．３３％。     

狼紫草籽油中脂肪酸组成的研究

采用毛细管气相色谱法测定了狼紫草籽油中的脂肪酸组成及相对含量。鉴定了１５种脂肪酸，占脂肪酸总量的９９．３％。样品所含主要脂肪酸为棕榈酸、油酸、亚油酸、α—亚麻酸和γ—亚麻酸。不饱和脂肪酸为９０．６４％，其中α—亚麻酸２６．８８％，γ—亚麻酸６．７０％。     

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.