SPME与SD提取八角茴香挥发性风味成分的GC-MS比较

目的:比较固相微萃取法(SPME)和水蒸气蒸馏法(SD)法提取的八角茴香挥发性风味成分的差异。方法:采用气相色谱-质谱(GC-MS)联用技术对2种方法提取的八角茴香挥发性成分进行分析。结果:2种方法分别鉴定了41种和21种挥发性成分,占各自挥发性成分总量的93.29%和90.20%,其中含量最高的化学成分均为反式茴香脑。结论:固相微萃取法可以萃取到很多水蒸气蒸馏法无法得到的物质,如异松油烯、萜品烯、金合欢烯、α-胡椒烯等。     

不同方法提取艾纳香叶挥发性成分的气相色谱-质谱分析

采用气相色谱-质谱法(GC-MS)分析水蒸汽蒸馏法(SD)、同时蒸馏萃取法(SDE)和顶空固相微萃取法(HS-SPME)3种方法提取的艾纳香叶挥发性成分。结果表明:3种方法提取艾纳香叶挥发性成分中主要是醇类和烯类化合物,其中萜类物质占较大比例。3种方法的提取物中分别鉴定出化合物50种(SD)、24种(SDE)和49种(HS-SPME)。水蒸汽蒸馏法和同时蒸馏萃取法提取的油状挥发物中主要成分相似,水蒸汽蒸馏法提取油状挥发物与顶空固相微萃取法提取挥发性成分的种类和相对含量相似,同时蒸馏萃取法提取油状挥发物中低沸点化合物较少。     

不同方法提取木姜子花蕾挥发油成分的比较研究

木姜子是我国南方特有的香料植物,其枝叶、花蕾、果实都能散发出芳香的气味,被广泛应用于食品添加剂和烹饪调料中。为了提取木姜子风味更浓郁的挥发油,分别采用水蒸气蒸馏法(SD)、超声辅助水蒸气蒸馏法(UASD)、微波辅助水蒸气蒸馏法(MASD)、超临界CO_2萃取法(SCFE)对木姜子花蕾中的挥发油成分进行提取,经SPME-GC-MS进行分析,研究结果表明,不同的提取方法所得挥发油组分不完全相同,但主要化学成分基本一致,采用超声辅助水蒸气蒸馏法最适合提取木姜子花蕾中的挥发油,共鉴定出49种挥发性物质,占挥发性成分的99.93%,其中影响木姜子花蕾中挥发油主要呈香风味物质柠檬醛、柠檬烯、罗勒烯、月桂烯、芳香醇的相对含量达到76.33%,由此可见该方法可获取风味更浓郁的木姜子挥发油。     

马格努门啤酒花挥发性成分的气相色谱-质谱联用分析

采用顶空固相微萃取-气相色谱-质谱联用的方法研究马格努门啤酒花中的主要挥发性成分的组成和含量,并与传统的水蒸气蒸馏方法所得到的精油成分进行比较,定性采用质谱谱库检索结合保留指数进行验证。结果表明:两种方法测得的啤酒花中的挥发性成分存在较大的差异。顶空固相微萃取法共鉴定出73种成分,占总峰面积质量分数的99.35%,以葎草烯、石竹烯为主要成分的萜烯类化合物的质量分数达85.35%,其氧化产物仅为0.24%;水蒸气蒸馏法共鉴定出63种化合物,占总峰面积质量分数的98.42%,其中萜烯类化合物的质量分数仅为68.41%,而萜烯类的氧化产物的质量分数达13.27%。而其他含氧化合物醇类、酯类和酮类,两种方法测定结果比较接近,其中,顶空固相微萃取法中的质量分数依次为2.65%、8.14%、1.29%;水蒸气蒸馏法依次为3.42%、10.55%、2.51%。此外,顶空固相微萃取法还检测到3个质量分数占到0.99%的醛类化合物,而水蒸气蒸馏法得到的精油中未检出该类组分。分析结果表明,马格努门啤酒花中的主要挥发性成分为葎草烯、β-香叶烯、β-石竹烯、葎草烯氧化物、石竹烯氧化物、δ-杜松烯、依兰油烯、4-癸烯酸甲酯、古巴烯、丙酮、γ-杜松烯、α-蛇床烯、β-蛇床烯、β-蒎烯、里哪醇、(E)-β-法呢烯、甲酸香叶酯。     

不同提取方法对安化茯砖茶挥发油成分的影响

分别采用水蒸气蒸馏法(SD)、同时蒸馏萃取法(SDE)、超声波溶剂萃取法(UAE)和固相微萃取法(SPME)提取安化茯砖茶的挥发油成分并通过GC-MS对4种方法的提取物成分进行了比较。结果表明,4种方法提取安化茯砖茶挥发性成分中主要是萜以及醛、酮、酸、酯类化合物。4种方法的提取物中分别鉴定出化合物86种(SD)、69种(SDE)、64种(UAE)和81种(SPME),其香气成分和相对含量比例有一定的差异。SD法提取油状挥发物与固相微萃取法提取挥发性成分的种类最多,在低沸点的组成上相类似。同时蒸馏萃取法和超声波溶剂萃取法提取挥发性成分中高沸点化合物含量较多。实验结果为选择合适的安化茯砖茶挥发油的提取分析方法及其制取方法提供参考。     

陈皮挥发性成分的提取与分析

采用顶空固相微萃取法和同时蒸馏萃取法提取陈皮中的挥发性成分,并利用气相色谱-质谱联用对其进行分离鉴定,共鉴定出89 种挥发性成分,其中烯烃类44 种、醇类10 种、醛类10 种、酚类8 种、酯类7 种、酮类4 种、其他物质6 种,两种方法均鉴定出的挥发性成分有34 种。对陈皮香气特征贡献较大的主要有D-柠檬烯、γ-松油烯、2-崖柏烯、α-金合欢烯、对-伞花烯、α-蒎烯等。     

GC-MS分析不同产地花椒挥发性成分

为考察5个不同产地花椒挥发性成分差异,分别采用水蒸气蒸馏法(water-steam distillation,WD)、顶空固相微萃取法(headspace solid-phase microextraction,SPME)和同时蒸馏法(simultaneous distillation,SD)3种提取方法结合气相色谱-质谱联用仪(GC-MS)分析山东花椒的挥发性成分。采用顶空固相微萃取提取5个产地花椒的挥发性物质,共鉴定出77种挥发性物质。采用主成分分析(PCA)寻找潜在标记特征物质,乙酸芳樟酯和乙酸松油酯作为潜在标记物,可区分5个不同产地花椒。研究结果对综合利用不同产地花椒具有重要的意义。     

粮食香气成分分析方法的研究

用顶空-固相微萃取法和同时蒸馏萃取法研究了酒用粮食中的挥发性香气成分,采用不同极性和不同膜厚的萃取头进行顶空固相微萃取,使用二氯甲烷、乙醚等作为有机溶剂进行同时蒸馏,用GC/MS对萃取成分进行定性检测。结果表明,顶空-固相微萃取法宜采用中等极性和中等膜厚的萃取头,同时蒸馏萃取法用二氯甲烷作为有机溶剂较合适,两种方法结合可以更全面地测定粮食的香气成分。     

不同方法提取西藏黑木耳中挥发性成分的气相色谱-质谱分析

为了探讨不同方法提取西藏黑木耳中的挥发性成分的化学组成,采取水蒸气蒸馏法和有机溶剂浸提法对黑木耳的挥发性成分进行提取,并采用GC-MS方法对提取的挥发性成分进行鉴定。水蒸气蒸馏法中鉴定了61个化学成分,主要成分是棕榈酸、亚油酸等;二氯甲烷浸提法中鉴定了36个化学成分,主要成分是麦角甾醇、5,8-麦角甾二烯-3β-醇等;乙醚浸提法中鉴定了26个化学成分,主要成分是麦角甾醇、亚油酸。     

不同提取方法对芸香科柑橘属植物佛手和柠檬挥发性成分研究

采用水蒸气蒸馏法(SD)与固相微萃取法(SPME)提取富集黔产佛手果和柠檬中果皮挥发油,结合气质联用技术(GC-MS)分析两者的挥发性成分。结果从佛手果鉴定出68种成分,柠檬果皮中鉴定出67种成分,两种同属植物挥发油中具有43种相同的化合物,主要是柠檬烯、β-蒎烯、α-蒎烯等;而成分相对含量不同及微量成分组成不同导致了他们具有各自的风味特征。本文研究结果为两种提取技术的进一步应用提供了参考,同时为两种同属植物在产品运用与开发、风味改善等方面提供了理论依据。     

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.     

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.     

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.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.