高良姜精油和纯露的体外抗氧化活性及酪氨酸酶抑制活性研究

以超临界流体辅助提取的高良姜精油和纯露为研究对象,测定其总抗氧化能力、ABTS+自由基清除能力、DPPH自由基清除能力、羟自由基清除能力,并与水蒸气蒸馏法所得高良姜精油和纯露比较,结果表明,采用超临界法辅助提取的高良姜精油和纯露具有比采用传统的水蒸气蒸馏法所得的对应样品更佳的体外抗氧化活性;超临界辅助提取高良姜精油对L-酪氨酸酶的抑制率,最高约为64%,明显高于阳性对照熊果苷对L-酪氨酸酶的抑制率。     

微胶囊化高良姜精油对冷藏金鲳鱼鱼糜的保鲜效果及凝胶特性影响

采用罗望子胶(CTG)与阿拉伯胶(GA)分子包埋法制备微胶囊高良姜精油,并将其应用于金鲳鱼鱼糜的保鲜,研究不同添加量的微胶囊化高良姜精油对鱼糜在冷藏过程中保鲜效果及凝胶特性的影响。结果表明:以罗望子胶与阿拉伯胶为壁材,通过包埋法制得的高良姜精油微胶囊具有缓释的能力;在冷藏条件下,添加微胶囊化高良姜精油可以有效地降低金鲳鱼鱼糜细菌菌落总数(TVC)、挥发性盐基氮(TVB-N)、p H值、TBA值。随着微胶囊添加量的增加,凝胶化鱼糜产品的凝胶强度呈现明显增加。     

无溶剂微波萃取没药精油及其在卷烟加香中的应用

采用无溶剂微波萃取法从没药中提取精油,测定了其物理性质,鉴定了主要功能团,GC/MS法分析了没药精油的主要化学成分,并进行了卷烟加香试验。结果表明:①最佳萃取条件为没药粉碎粒度40目,浸润时间3 h,微波功率800 W,萃取时间21 min;此条件下精油得率为3.95%。②共鉴定出62种化合物,主要包括异乌药根烯、莪术烯、乌药根烯、α-柏木烯和β-榄香烯等。③没药精油能改善和修饰卷烟烟气,有效降低杂气,改善吸味和余味,减少刺激。     

水蒸气蒸馏法提取辛夷精油及在卷烟加香中的应用研究

利用水蒸气蒸馏法提取辛夷中的精油，研究了在不同提取条件下辛夷精油的出油率和精油的质量。试验表明：在利用水蒸气蒸馏法提取辛夷精油时，蕊和壳应粉碎并分开蒸馏，最佳浸泡时间和蒸馏时间分别为24h和4h，在此条件下，辛夷蕊、壳的出油率分别为2．7％和0．57％。用辛夷精油进行卷烟加香试验，结果表明：辛夷精油能明显改善和修饰卷烟香气，降低烟气的粗糙度，改善吸味，减轻刺激性，去除杂气。     

高良姜精油微胶囊的制备及其对猪肉糜的保鲜效果

采用复凝聚法制备得到高良姜精油微胶囊并将其应用于猪肉糜的保鲜,研究不同质量分数微胶囊添加量对肉糜在10 d冷藏期间菌落总数、脂肪氧化程度(TBA值)和高铁肌红蛋白(Met Mb)含量的影响。结果表明:以壳聚糖和海藻酸钠为壁材制备的高良姜精油微胶囊能缓慢释放精油,对大肠杆菌、金黄色葡萄球菌和酵母菌有良好的抑菌效果。用于肉糜保鲜,与对照组相比,所有处理组均能抑制肉糜微生物生长,降低其TBA值和MetMb含量。其中,添加质量分数0.1%和0.2%微胶囊对肉糜有较好的保鲜作用且效果接近,而0.05%微胶囊保鲜效果不明显。结论:添加0.1%高良姜精油微胶囊可以提高肉糜品质,延长肉糜冷藏的货架期。     

麦芽精油成分研究及其在卷烟中应用

采用水蒸气蒸馏法提取普通麦芽、炒麦芽和焦香麦芽的精油组分,通过GC-MS方法分析不同麦芽精油的主要化学成分,并对制备出的精油进行了卷烟添加实验。结果表明:不同麦芽的精油中均含有棕榈酸及其酯类,但其他化学成分差异较大,造成了它们在卷烟中不同添加效果。焦香麦芽精油中含有大量的吡嗪类化合物、糠醛类衍生物和麦芽酚,加入到卷烟中表现出突出的焦甜香韵,是较好的焦甜香香原料。      

玫瑰精油香味成分分析及在卷烟加香中的应用

为考察不同玫瑰精油的香味成分差异及对卷烟烟气感官质量的影响,通过优化前处理和仪器条件,采用顶空-固相微萃取-气相色谱质谱联用(HS-SPME-GC/MS)方法分析了5种玫瑰精油样品。结果表明:(1)优化确定的实验条件为,50μL玫瑰精油样品,用粉色萃取头在80℃下萃取30 min,解吸3 min后进行GC/MS分析。(2)从5种玫瑰精油样品中共检测出191种香味成分,包括醇类52种、烯类42种,酯类39种、醛类15种、烷烃15种、酮类8种和其他成分20种;主要的香味成分为醇类物质。(3)5种玫瑰精油样品香味成分的选择相似性指数(SSI)分析表明,共检出指标相似度最高的样品为保加利亚玫瑰精油-土耳其玫瑰精油,其次是保加利亚玫瑰精油-中国甘肃玫瑰精油。(4)感官评价结果表明,5种玫瑰精油样品中,保加利亚玫瑰精油的卷烟加香效果最好;与保加利亚玫瑰精油样品相比,玫瑰精油样品的香味成分SSI越高,则加入该精油的卷烟烟气感官质量越好。     

香橼叶挥发性化学成分及其在卷烟加香中的应用研究

应用同时水蒸气蒸馏-溶剂萃取方法(SDE)提取新鲜香橼叶精油,通过GC-MS技术从中鉴定出30种化学成分,其中主要成分有柠檬烯、橙花醛、香叶醛、香茅醛等.香橼叶挥发油的卷烟加香试验表明,它能明显改善和修饰卷烟香气,增加烟香,提高香气品质.     

几种植物精油对赤拟谷盗成虫的熏蒸作用

在14.7μL/L的剂量下,测试了八角茴香油、高良姜油、臭椿油、留兰香油、艾蒿油、黄樟油、薄荷油、山苍子油、辣椒油、石菖蒲油、肉豆蔻油、姜黄油、广藿香油、香茅油和芥菜油等15种植物精油对赤拟谷盗Tribolium castaneum(Herbst)成虫的熏蒸活性,结果表明八角茴香油、高良姜油、臭椿油、留兰香油、艾蒿油和黄樟油等6种植物精油对赤拟谷盗成虫具有熏蒸活性,其中八角茴香油和高良姜油的效果较好.八角茴香油对赤拟谷盗成虫的熏蒸毒力测定结果表明,当熏蒸处理24、48、72 h时,其LC50值分别为14.39、7.44、7.03μL/L.高良姜油的测定结果表明,在24、48、72 h的熏蒸处理条件下,LC50值分别为25.48、17.93、15.79μL/L.     

烟草精油研究及应用进展

烟草精油是烟草中的次生代谢物,主要由挥发性和半挥发性成分组成,是烟草香味的重要来源。目前,烟草精油主要作为香精香料应用于卷烟工业。本文就烟草精油概念、化学成分、提取方法、分析方法和应用方面的研究进展进行综述,并对烟草精油的应用前景进行探讨。     

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