超临界CO2萃取省沽油籽油及其化学成分研究

对省沽油籽油的萃取工艺及其化学成分进行研究。采用超临界CO2萃取技术,用正交试验法研究省沽油籽油的萃取工艺,确定最佳萃取条件;并用GC-MS方法分析省沽油籽油的化学成分。结果表明：省沽油籽油的超临界CO2萃取条件为：萃取釜压力25MPα,温度50℃,萃取2h,萃取率为28．83％;省沽油籽油中共分离出48种成分,确认结构31种,占总峰面积的81．10％。其中低沸点成分主要是E,E-2,4-癸二烯醛和E,E-2,4-壬二烯醛;省沽油籽油的主要化学成分是亚油酸,其相对含量为53．30％;另外还含有较高含量的角鲨烯（7．12％）、维生素E（4．45％）和β-谷甾醇（3．21％）等。这些化合物具有很高的生物活性,其中β-谷甾醇为首次从省沽油籽油中分离得到。     

超临界CO2萃取山楂籽油及其化学成分分析

采用超临界CO2萃取技术,对山楂籽油萃取工艺进行了研究,并用GC-MS法分析了山楂籽油的化学成分.结果表明:超临界CO2萃取山楂籽油的最佳工艺条件为:萃取釜压力30 MPa,温度40℃,萃取时间3 h,在此条件下,萃取率达6.53%;山楂籽油中共分离出36种成分,确认结构31种,占总峰面积的76.27%,其中低沸点成分主要是E,E-2,4-壬二烯醛和壬醛等;山楂籽油的主要化学成分是油酸、亚油酸及其酯类,其质量分数超过31.12%,另外还含有较高质量分数的维生素E(9.18%)、角鲨烯(6.02%)、β-谷甾醇(4.76%)、二十八烷醇(0.82%)等.     

山楂籽油化学成分及抗氧化活性的研究

对山楂籽油的化学成分、脂肪酸组成进行了研究,测定了山楂籽油中角鲨烯、维生素E、总黄酮、总多酚含量,利用DPPH和ABTS法评价山楂籽油的体外抗氧化活性。结果表明:通过GC-MS,初步确认了23种化学成分,其中亚油酸、油酸及其脂类、角鲨烯为主要成分。通过对山楂籽油的脂肪酸分析,鉴别出14种脂肪酸,主要为不饱和脂肪酸(89%);测定角鲨烯含量为(236. 64±13. 20) mg/kg,HPLC法分别测定4种亚型维生素E的含量,含量最高的为γ-生育酚,达到(51. 92±2. 53) mg/100 g,测定了总多酚和总黄酮含量,分别为(424. 59±11. 25)、(103. 33±5. 86) mg REs/100 g DW,这些物质均有很好的抗氧化活性。利用DPPH和ABTS法评价了山楂籽油的抗氧化活性,结果显示山楂籽油对DPPH和ABTS有很好的清除能力,清除率均达到90%以上。     

苹果籽油中维生素E含量的测定及提取方法比较

采用荧光分光光度法对苹果籽油中的维生素E含量进行测定,试验发现:苹果籽油中的维生素含量达249.0 mg/100 g油,且采用超临界CO2萃取的苹果籽油中维生素E含量高于有机溶剂提取.     

省沽油种仁油脂肪酸及不皂化物分析

采用GC-MS分析省沽油种仁油中脂肪酸和不皂化物的组成与含量。结果表明:省沽油种仁油中不饱和脂肪酸含量达86.68%,主要为油酸、亚油酸和亚麻酸;油中不皂化物共鉴定出6种植物甾醇、3种烯烃、1种维生素和12种烷烃类化合物,其中γ-谷甾醇、角鲨烯和维生素E含量最高,分别为411.21、257.72 mg/kg和151.94 mg/kg,经质谱离子碎片对比分析,省沽油种仁油中的维生素E为α-生育酚。     

裸仁南瓜籽油活性成分分析及抗氧化能力评价

以超临界CO2萃取的裸仁南瓜籽油为研究对象,根据LS/T 3250—2017《南瓜籽油》标准检测其质量指标,运用气相色谱—质谱(GC-MS)联用仪分析脂肪酸和植物甾醇组分,高效液相色谱(HPLC)仪测定角鲨烯含量;以葡萄籽油和亚麻籽油作为对比,研究裸仁南瓜籽油对DPPH、ABTS自由基的清除能力,以评价其抗氧化活性。结果表明,超临界CO2萃取的裸仁南瓜籽油符合LS/T 3250—2017标准,裸仁南瓜籽油主要含有4种不饱和脂肪酸,总含量为74.73%,其中顺式单不饱和脂肪酸和多不饱和脂肪酸含量分别为29.14%,45.54%;富含植物甾醇,β-谷甾醇含量为30.75%,△-7植物甾醇含量达10.77%;角鲨烯含量为5 490μg/g,高达葡萄籽油的80倍,亚麻籽油的279倍;裸仁南瓜籽油具有良好的抗氧化活性,其抗氧化性与油浓度呈正相关,对DPPH自由基的清除能力(IC50为16.14 mg/mL)优于葡萄籽油、亚麻籽油,对ABTS自由基的清除能力(IC50为10.46mg/mL)优于亚麻籽油,裸仁南瓜籽油良好的抗氧化活性可能与其丰富的角鲨烯、植物甾醇和不饱和脂肪酸有关。     

马鲁拉油与6种植物油理化性质、脂肪酸组成、营养物质比较

比较了马鲁拉油和6种常见植物油(橄榄油、花生油、玉米油、葵花籽油、紫苏籽油、亚麻籽油)的脂肪酸组成、理化性质及角鲨烯、维生素E和β-谷甾醇等营养物质含量的差异。结果表明:马鲁拉种仁出油率高达51.93%;马鲁拉油中角鲨烯和β-谷甾醇含量分别为2.5 mg/100 g和183.5 mg/100 g;马鲁拉油中的油酸含量高达76.94%,橄榄油中油酸含量为67.39%;与常见植物油相比,马鲁拉油富含单不饱和脂肪酸,脂肪酸比例均衡,且富含营养物质,适于人体的吸收,具有开发应用的潜力。     

制油工艺对紫苏油品质的影响研究

研究压榨、浸提与超临界CO2萃取3种工艺制得的紫苏油中脂肪酸组成、挥发物、不皂化物、维生素E的种类及含量差异,分析不同工艺对紫苏油品质的影响.结果表明,脱壳紫苏籽超临界CO2萃取工艺制得的紫苏籽油中亚麻酸含量和维生素E含量最高;通过脱壳处理能显著降低超临界CO2制备紫苏籽油的蜡质含量,提高紫苏油品质.脱壳紫苏籽超临界C...     

气相色谱-质谱联用测定南瓜籽油中角鲨烯的含量

基于GB/T 22110—2008方法,建立一种简单、快速测定南瓜籽油中角鲨烯含量的气相色谱-质谱联用(GC-MS)方法,考察了甲酯化试剂浓度对角鲨烯提取效果及不同极性色谱柱对角鲨烯分离程度的影响,确定南瓜籽油中角鲨烯含量测定的最佳条件。结果表明,0.2 g南瓜籽油经1 m L0.5 mol/L的氢氧化钾-甲醇溶液进行甲酯化反应,正己烷提取后经极性色谱柱HP-FFAP分离,用GC-MS选择离子监测模式对角鲨烯可以进行定量测定。该方法在10~500 mg/L范围内线性关系良好,相关系数r=0.999 9;检出限为0.12 mg/kg,加标回收率为79.33%~91.33%,平均相对标准偏差为3.99%。采用该方法测定的14种市售南瓜籽油中角鲨烯平均含量为1.44 g/kg。     

辣木籽油的超临界CO_2萃取及其化学成分分析

研究了超临界CO2流体萃取辣木籽油的工艺条件并对其化学成分进行了分析。考察了在超临界CO2条件下,萃取时间、萃取压力、萃取温度、CO2流量和分离温度等因素对出油率的影响,并通过正交试验优化得到最佳工艺条件,最后用GC-MS法测定辣木籽油的化学组成。结果显示最佳工艺条件为:萃取时间180 mm,萃取压力20 MPa,CO2流量20 kg/h,萃取温度35℃,分离温度40℃,在此条件下出油率为36.3%,提取率为97%。GC-MS测定结果显示辣木籽油主要由脂肪酸组成,总的质量分数为92%,其中含油酸65.63%;此外还含有1%~3%的饱和烃(1.07%)、醛和醚(1.76%)、酯(2.85%),1.95%的菜油甾醇、豆甾醇、β-谷甾醇和岩藻甾醇。揭示了用超临界CO2法萃取辣木籽油是可行的;辣木籽油是一种富含油酸、甾醇等功能性成分的植物油。     

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.     

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.     

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.     

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.     

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.     

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