大豆油脱臭馏出物酶法甲酯化工艺研究

Eversa Transform 2. 0脂肪酶价格低、催化活性好,具有微量高效的优点。以Eversa Transform2. 0脂肪酶为催化剂,对大豆油脱臭馏出物进行酶法甲酯化工艺研究。通过单因素试验研究了醇酸摩尔比、酶用量、反应温度、反应时间对酯化率的影响,并进行正交试验,对酶法甲酯化工艺进行优化。在最佳工艺条件下,通过放大试验对试验结果进行验证,并采用薄层色谱法对甘油三酯的转化进行分析。结果表明:Eversa Transform 2. 0脂肪酶催化大豆油脱臭馏出物甲酯化反应的最佳工艺条件为醇酸摩尔比(甲醇与游离脂肪酸摩尔比) 2∶1、酶用量0. 3%(相对于大豆油脱臭馏出物的质量)、反应温度35℃、反应时间6 h,在此条件下酯化率达到95%以上,且甘油三酯基本反应完全。     

固体酸催化大豆油脱臭馏出物甲酯化工艺研究

采用溶胶-凝胶和浸渍法制备了SO2-4/TiO2-SiO2固体酸催化剂,利用其对大豆油脱臭馏出物进行甲酯化。研究了TiO2-SiO2载体焙烧温度、浸渍用硫酸浓度、浸渍时间对催化剂活性的影响,以及催化剂用量、醇油比、反应温度和反应时间对酯化率的影响。得到了最佳反应条件为载体焙烧温度550℃,浸渍用硫酸浓度2.5 mol/L,浸渍时间12 h,催化剂用量5%(以大豆油脱臭馏出物质量计),醇油比1.5∶1(甲醇与大豆油脱臭馏出物体积质量比),反应温度65℃,反应时间4 h。在最佳条件下,酯化率达到96.5%。     

新疆棉籽油脱臭馏出物酶法甲酯化工艺研究

以新疆棉籽油脱臭馏出物为研究对象,采用Novozyme435脂肪酶催化其中的游离脂肪酸进行甲酯化反应,通过单因素试验对影响酯化反应的反应温度,反应时间,酶用量及酸醇比4个因素进行优化,选取最佳的工艺参数。在单因素试验的基础上应用响应面设计确定最优的棉籽油脱臭馏出物脂肪酸甲酯化反应的工艺参数。结果表明,棉籽油脱臭馏出物甲酯化最优工艺条件是反应温度60 ℃,酶用量62.86 plu/g,反应时间9 h和酸醇比1.00∶1.65（g∶mL）,模型预测酯化率97.27%,实际试验值为（97.09±0.09）%,基本与预测值一致。     

微波辅助绿豆碳基固体酸催化剂活性研究

为了考察微波辐射对自制固体酸催化剂催化活性的影响,作者以绿豆为原料,采用碳化-磺化法制备了一种新型碳基固体酸催化剂,于实验室自制微波反应器中催化油酸和甲醇的酯化反应。对油酸甲酯化反应过程中的微波功率、反应温度、反应时间、催化剂用量、醇油摩尔比等条件进行了单因素分析,并对醇油摩尔比、反应时间、催化剂用量对油酸甲酯化的转化率的影响进行了正交优化,得到最佳工艺为:微波功率400 W、反应温度65℃、醇油摩尔比11∶1、反应时间30 min、催化剂用量为5%,在此工艺条件下油酸甲酯化的转化率为93.97%。     

文冠果种子油制备生物柴油工艺的研究

以文冠果种子油为原料,通过甲酯化反应制备生物柴油,采用气相色谱法测定产品生物柴油中脂肪酸甲酯的含量。考察了醇油摩尔比、催化剂用量、反应温度、反应时间对脂肪酸甲酯含量的影响。确定了最佳工艺条件为：醇油摩尔比8∶1,催化剂用量为油重的1.2%,反应温度65℃,反应时间120 min。     

玉米油脱臭馏出物固体酸催化的甲酯化反应条件优化

对玉米油脱臭馏出物中的脂肪酸采用强酸性阳离子交换树脂催化甲酯化反应。对树脂进行筛选、预处理、干燥,确定以干燥的干氢NKC-9强酸性树脂作为甲酯化催化剂。对反应条件进行单因素试验,确定了最佳反应工艺参数。经正交试验优化确定甲酯化反应最佳条件为:甲酯化反应温度为60℃,甲酯化反应时间为5h,醇酸比为2∶1,催化剂用量为20%。最佳条件下脂肪酸甲酯化率可达到97.8%。     

酶法提取番茄籽油脱臭馏出物中维生素E的研究

试验以番茄籽油脱臭馏出物为原料,以脂肪酶为催化剂,通过酶法甲酯化,再将甲酯化产物结晶,分离甾醇后用正己烷提取维生素E的相关工艺及参数进了行研究。试验确定脂肪酶最佳反应体系为水相体系,结合响应面优化试验,确定最佳反应条件:料液比1︰5(mg/m L)、酶用量500 U/g、反应温度40℃、反应时间16 h和水分含量为26%时,番茄籽油脱臭馏出物中维生素E总提取率可以达到42.78%,与模型理论预测值43.45%接近。     

脱臭馏出物提取VE的酶预处理

研究了以大豆油脱臭馏出物为原料,采用脂肪酶Novozym435为催化剂,催化脂肪酸与甲醇的酯化反应。反应最佳工艺条件为:反应试剂摩尔比(甲醇∶脱臭馏出物中游离脂肪酸)为2.2∶1,催化剂用量为2.5%,反应温度为35℃,反应时间为10 h。在最佳反应条件下酯化率为95.9%。     

大豆油脱臭馏出物的酶法甲酯化新工艺

采用酶法研究大豆油馏出物甲酯化的工艺。对反应条件进行单因素分析和正交试验,确定了反应的最佳工艺参数。试验结果表明:影响转化率的主要因素是反应时间和酶用量,反应温度和底物比影响其次。最佳甲酯化工艺条件为:料溶摩尔比1:1.5,酶用量60plu/g,反应温度60℃,反应时间8h,该条件下转化率达94.78%。     

麻疯树籽油甲酯化工艺的研究

以低温压榨麻疯树籽油(经过水化脱胶、溶剂萃取脱酸和脱水,使油脂酸值在1 mgKOH/g以下,水分在0.1%以下.)为原料,甲醇钠作催化剂,考察了甲酯化反应条件如醇油比、催化剂用量、反应温度、反应时间对麻疯树籽油甲酯转化率和得率的影响.经正交实验确定甲酯化最佳条件为:反应温度65℃,醇油摩尔比7:1,反应时间60min,催化剂用量为油重的0.9%.在最佳反应条件下,甲酯转化率为95.09%,产品得率为88.88%.反应产物经水洗、脱水并过滤后,即得脂肪酸甲酯.     

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.