专用硅胶在油脂精炼生产中的应用研究

利用专用硅胶对油脂进行吸附脱胶、吸附脱皂、吸附脱色及脱除氯离子,通过对工艺条件和脱除效果的研究,评价其在油脂精炼生产中应用的可行性。结果表明:利用SORBSILR92硅胶对浓香花生油进行吸附脱胶,在硅胶添加量0. 5%、吸附温度80℃、吸附时间15 min条件下,磷脂脱除率为96. 2%,且脱胶油色泽清亮、风味保留好;利用SORBSILR92硅胶对碱炼脱酸后的大豆油进行脱皂处理,可使大豆油含皂量从130. 7 mg/kg降至未检出,与水洗脱皂相比,不仅能明显降低含皂量,还实现了脱皂过程的废水零排放,减少了脱皂过程的油脂损耗;利用SORBSILR40F在优化条件下对大豆油脱色(先向待脱色油中添加0. 08%的SORBSILR40F硅胶,吸附反应后再添加1. 57%的活性白土)后,其含磷量明显低于单纯活性白土脱色油,并且脱臭油的色泽、氧化稳定性也优于单纯活性白土脱色脱臭油;利用SORBISILR40F硅胶和SORBSILR92硅胶在100℃、20 min条件下对大豆油进行吸附处理,大豆油中氯离子含量分别降低28. 47%和18. 98%,这对防范和降低油脂脱臭过程3-氯丙醇酯和缩水甘油酯的形成是有利的。综上,专用硅胶SORBSILR92和SORBSILR40F在油脂精炼工艺技术的改进发展方面具有很好的应用前景。     

油脂脱酸过程中碱炼效果优化研究

油脂脱酸处理过程一般采用氢氧化钠溶液进行处理,在去除原料油中游离脂肪酸和磷脂的同时,也会形成产生大量的皂,如果皂不能被有效脱除,会增大油脂后续的加工难度。本文通过对油脂脱酸过程中碱炼的实验条件的研究和优化,确定了在碱反应温度为75℃、碱反应时间为20 min、水洗温度为92℃、水洗水添加量为8%、柠檬酸添加量为0.04%时,可以有效的将脱酸油的含磷量控制在5 mg/kg左右,含皂量控制在30 mg/kg内,为油脂后续的精炼打下良好的基础。     

二氧化硅作为新型环保吸附剂在食用油中的 高效吸附作用

针对常规油脂脱色存在油脂色泽过浅的问题,以活性白土作对比,将二氧化硅用于葵花籽油的脱色,通过测定不同添加量二氧化硅脱色葵花籽油的色泽、杂质含量、氧化诱导期及风险物质含量,考察二氧化硅的吸附脱色效果。结果表明：二氧化硅（0.1%~0.5%）添加量脱色葵花籽油的磷含量、苯并（a）芘和黄曲霉毒素B1含量与0.5%活性白土脱色葵花籽油的相当,但与0.5%活性白土相比,0.1%二氧化硅脱色可以在保持葵花籽油色泽的同时,达到葵花籽油中的皂未检出和氧化诱导期显著延长的效果,说明二氧化硅在食用油中具有较好的吸附脱色效果。     

大豆油酶法脱胶和硅胶吸附脱皂效果研究

利用PLA1脱除大豆毛油中的磷脂,再用硅胶吸附脱除大豆油中的残磷和残皂。以酶法脱胶后含磷量、硅胶吸附脱皂后的含磷量和含皂量为评价指标,研究酶法脱胶及硅胶吸附脱皂对大豆油脱胶脱皂效果的影响。结果表明：在大豆油pH 5.5～6、去离子水添加量3%、反应时间6～8 h的脱胶条件下,酶法脱胶效果随PLA1添加量的增加而提高,PLA1添加量分别为50、75、100 mg/kg时,脱胶大豆油中含磷量分别从566.36、538.02、562.76 mg/kg降至44.67、18.99、17.01 mg/kg,再添加油质量0.1%的SORBSIL R92硅胶,大豆油含磷量分别降至41.21、16.35、15.42 mg/kg,含皂量分别从37、23、14 mg/kg降至14、8、5 mg/kg。酶法脱胶后大豆油酸值和过氧化值有所升高,3个油样的酸值（KOH）平均升高0.63 mg/g,过氧化值平均升高0.007 g/100 g。硅胶吸附脱皂也造成大豆油酸值和过氧化值有所升高。     

响应面试验优化玉米油二次脱皂新工艺

利用玉米油含蜡特性,即在低温脱蜡过程中,皂粒以晶核状态吸附蜡质结晶脱蜡,同时完成了一次脱皂。在脱色过程中,加入活性白土脱色,同时残余的微量皂被活性白土进一步吸附,达到了二次脱皂的效果。考察了碱炼油中含皂量、碱炼油中含水量、养晶时间和活性白土添加量对二次脱皂后脱色油中残皂量的影响。通过单因素试验和响应面优化试验确定玉米油精炼脱皂的最优工艺条件为:碱炼油中含皂量300 mg/kg,碱炼油中含水量0.4%,养晶时间24 h,活性白土添加量0.5%。在最优工艺条件下进行脱皂,得到脱色油中残皂量为0.19 mg/kg,脱皂率为99.9%。新工艺脱皂效果更好,而且不经过水洗过程,无废水排放,符合节能环保的工艺要求,而且简化了加工工艺。     

两级分子蒸馏深度脱除油脂中3-氯丙醇酯和缩水甘油酯

对3-氯丙醇（3-MCPD）酯和缩水甘油酯（GEs）含量超标幅度大的1个玉米油和2个稻米油样品分别进行两级分子蒸馏,研究两级分子蒸馏对油脂中3-MCPD酯和GEs的脱除效果,同时测定其对油脂中VE、甾醇和谷维素含量的影响。结果表明：3个油脂样品中3-MCPD酯含量为6169~16.008 mg/kg,超出欧盟建议限量（1.25 mg/kg）的3.94~11.81倍,GEs含量为7.004~56.399 mg/kg,超出欧盟限量（1.00 mg/kg）的6.00~55.40倍;经一级分子蒸馏,油脂中3-MCPD酯的脱除率为49%~68%,GEs脱除率为42%~90%;经二级分子蒸馏,油脂中3-MCPD酯和GEs的脱除率分别达到93%~96%和91%~98%,含量分别降低至0.368~0.932 mg/kg和0.545~0900 mg/kg,均明显低于欧盟限量;经二级分子蒸馏,3个油脂样品VE保留率为11%~14%,甾醇保留率为59%~75%,稻米油中谷维素保留率为88%~89%。采用两级分子蒸馏能实现油脂中高含量3-MCPD酯和GEs的深度脱除,但同时也会造成油脂中VE、甾醇等活性成分的较严重损失。因此,可根据油脂中3-MCPD酯和GEs的超标程度合理选用一级分子蒸馏或两级分子蒸馏。     

无水脱皂工艺在油脂精炼中的应用

分析脱皂离心机出油含皂和吸附剂用量对无水脱皂工艺的影响,确定合适的无水脱皂工艺参数,同时对无水脱皂工艺和常规水洗工艺的中和油品质进行了对比。结果表明,无水脱皂工艺在含皂300 mg/kg左右,吸附剂添加量为0.10%时可以顺利进行;无水脱皂工艺中和油品质优于常规水洗工艺,无水脱皂工艺的节能减排效益显著。     

油脂碱炼过程中无水脱皂工艺改造

在原600 t/d碱炼工艺中将常规水洗脱皂工艺调整成无水脱皂工艺,增加2台过滤机,减少1台水洗离心机,采用两次脱色工艺,添加硅藻土0.1% ～0.2%,脱去脱皂油中的磷脂和皂类,取消水洗,可减少废水排放40 kg/t,白土用量增加1.23 kg/t,减少用电0.93 kW·h/t,精炼油得率提高约0.1%,减少加工费8.99元/t.白土脱色后油中残磷量1～3 mg/kg,残皂量为0.     

植物油底物及碱炼条件对其β-胡萝卜素 含量的影响规律

旨在为食用油脂的精准适度加工提供理论依据,以大豆油为油样介质,通过添加β-胡萝卜素和不同脂肪酸改变油样组成,探究碱炼过程中不同植物油底物和碱炼条件（碱液质量分数、超量碱添加量、碱炼温度、碱炼时间）对油脂中β-胡萝卜素脱除率及油脂精炼得率的影响,并测定了油脂在不同植物油底物和碱炼条件脱酸后酸值的变化。结果表明：脂肪酸种类对β-胡萝卜素脱除率有显著影响,碱炼生成的饱和皂棕榈酸皂对β-胡萝卜素的脱除率最高（5.92%）,不饱和皂亚麻酸皂对β-胡萝卜素的脱除率最低（2.57%）;游离脂肪酸含量为1.2%时,β-胡萝卜素脱除率最高（4.09%）;油脂中β-胡萝卜素含量越多,β-胡萝卜素脱除率越高;碱液质量分数在12%~18%的中强碱有利于β-胡萝卜素的脱除,脱除率为3.73%~4.30%;随着超量碱添加量的增加,β-胡萝卜素脱除率先升高后降低,超量碱添加量为0.1%时,脱除率最高,为4.09%;碱炼温度越低,β-胡萝卜素脱除率越高,在30 ℃时β-胡萝卜素脱除率最高（4.46%）;随着碱炼时间的延长,β-胡萝卜素脱除率不断增加,在碱炼时间超过30 min后,β-胡萝卜素脱除率增长变缓;棕榈酸、硬脂酸显著降低油脂的精炼得率;随着碱液质量分数、超量碱添加量、碱炼温度、碱炼时间、游离脂肪酸含量的增加,油脂精炼得率总体呈下降趋势,β-胡萝卜素含量对油脂精炼得率无显著影响;除含有大量月桂酸的植物油外,碱炼脱酸可以有效地将油脂酸值（KOH）控制在0.04~0.22 mg/g之间。综上,低温、中强碱有助于β-胡萝卜素的脱除,适当缩短碱炼时间有助于β-胡萝卜素的保留。     

玉米油中黄曲霉毒素B_1的吸附脱除效果研究

以玉米油中黄曲霉毒素B_1(AFB_1)脱除率为主要考察指标,研究不同吸附剂、吸附剂添加量以及吸附时间、吸附温度对玉米油中AFB_1的脱除效果和最佳脱除条件。结果表明:当吸附剂添加量为油质量的2%时,活性白土、凹凸棒石、WY1活性炭、WY2活性炭及普通活性炭对玉米毛油中AFB_1的脱除率分别为98.04%、97.66%、94.35%、95.72%和75.71%,AFB_1含量由39.28μg/kg分别降至0.77、0.92、2.22、1.68、9.54μg/kg,明显优于GB 2716—2005《食用植物油卫生标准》中规定的AFB_1含量小于等于20μg/kg的限量指标;在玉米油吸附脱色的精炼过程中,选用活性白土或凹凸棒石或WY2活性炭、添加量2%、吸附时间25 min、吸附温度100℃的工艺条件,可将玉米毛油中AFB_1含量降至欧盟要求的小于等于2μg/kg的限量指标;若综合考虑AFB_1脱除、吸附剂成本及油脂损耗,可适当降低吸附剂添加量,当WY1和WY2活性炭添加量为1%时,可将玉米毛油中AFB_1含量分别降至3.07、2.15μg/kg。     

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.     

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