主成分分析法综合评价面条品质

对29个中国北方的推广小麦品种制作的干白面条14个品质指标进行了全面测定，采用主成分分析法提取5个主成分指标构建数学评价模型，综合评价面条的各种品质，优选出了泰山23、洛展1号、豫农949、太空6号等优质的面条专用小麦品种。本研究在感官评价的基础上，将自然断条率、最佳蒸煮时间、蒸煮损失率、拉伸强度、拉断力等7项指标与感官评分指标一起对面条品质指标进行综合评定，     

不同品种马铃薯全粉面条品质特性及主成分分析

为研究不同品种马铃薯面条品质特性的差异及马铃薯的加工适宜性,分析了11个品种马铃薯全粉面条的品质特性,采用主成分分析对11个品种面条品质特性进行分析及综合评价。结果表明,不同品种面条品质特性差异显著(p0.05),面条的ΔE*与弹性(r=0.594*),最佳蒸煮时间与咀嚼性(r=0.748**)、内聚力(r=0.648*),咀嚼性与弹性(r=0.764**)、内聚力(r=0.836**),弹性与内聚力(r=0.625*),内聚力与粘结性(r=0.523*)呈显著的正相关性。主成分分析中前4个主成分的累积贡献率为85.77%,解释了原有面条品质特性的多数信息,第一主成分综合了口感特性、第二主成分综合了蒸煮特性、第三主成分综合了硬度特性、第四主成分综合了色泽特性;通过面条综合评价模型计算综合得分,评价较优的品种是陇薯9号、LZ111和陇薯7号。本研究为筛选适宜加工面条的马铃薯专用品种提供了依据。     

基于主成分分析与聚类分析的面条力学品质评价

为了探究不同类别挂面力学品质差异,以面条硬度、黏性、弹性、咀嚼性、抗拉强度、盐、添加剂、风味成分为评判指标,采用主成分分析和聚类分析来对面条力学品质进行评价。结果表明,通过主成分分析可以得到2个主成分,累计贡献率达85. 323%;再由聚类分析将面条分为三类,分别为零添加面条、劲道风味面条和玉带面。其中,主成分得分越高的面条其力学品质也越高;同一类面条力学品质相近且具有共同特点,同时主成分得分与感官评分结果一致,说明采用主成分分析与聚类分析来对面条进行评价分类是可行的。实验结果为利用面条力学性能的多个指标来对不同品种面条品质进行评价提供了一个方法参考。     

小麦及其面粉成分与面条品质相关性研究

本文从小麦籽粒物理性状与出粉率的关系、小麦粉成分与面条评分的关系、小麦粉的流变特性与面条评分的关系、小麦粉淀粉特性指标与面条评分的关系4个方面,对影响面条食用品质的相关性因素进行探讨;通过研究,发现蛋白质和淀粉共同影响面条食用品质;在14个小麦品种中以藁城8901、济南20、百农64、周麦12、白硬冬1号制面效果较好。     

小麦及其面粉成分与面条品质相关性研究

本文从小麦籽粒物理性状与出粉率的关系、小麦粉成分与面条评分的关系、小麦粉的流变特性与面条评分的关系、小麦粉淀粉特性指标与面条评分的关系4个方面,对影响面条食用品质的相关性因素进行探讨;通过研究,发现蛋白质和淀粉共同影响面条食用品质;在14个小麦品种中以藁城8901、济南20、百农64、周麦12、白硬冬1号制面效果较好。     

小麦品种籽粒品质与中国挂面品质关系研究

以5个中国小麦品种和8个法国小麦品种为材料,研究了拉伸参数、粉质参数、蛋白质品质、糊化参数等小麦品种籽粒品质与面条品质的关系;对比了中法小麦品种面条品质的差异,并对其形成原因进行了分析;探讨了试验原料、数据分析方法和试验方法等因素对试验结果的影响;探讨了用质构仪评价面条品质时的代表性品质指标。研究结果发现,45min时拉伸参数,稳定时间,沉淀值,加入酶活抑制剂时所测糊化参数可以做为评价中国小麦品种面条用面粉品质的主要依据;沉淀值可作为小麦品种选育过程中预测面条筋力的首选指标;由质构仪所测得的硬度和断裂能量可做为主要代表性指标分别反映面条的粘弹性和筋力特性。中国小麦品种的面条粘结性和煮制吸水率较大,最佳煮制时间和干物质失落率较小,干面条的抗弯强度和熟面条的硬度、咀嚼性和筋力较低。蛋白质质量和糊化特性较低是形成这种差距的主要原因。     

小麦及其面粉成分与面条品质相关性研究

结合粮食加工厂实际需要和实验室条件,从小麦籽粒物理性状与出粉率的关系、小麦粉成分与面条评分的关系、小麦粉的流变特性与面条评分的关系、小麦粉淀粉特性指标与面条评分的关系四个方面,对影响面条食用品质的相关性因素进行探讨;通过研究,发现蛋白质和淀粉共同影响面条食用品质;在14个小麦品种中以藁城8901、济南20、百农64、周麦12、白硬冬1号制面效果较好.     

小麦品种籽粒品质与中国挂面品质关系研究注

以5个中国小麦品种和8个法国小麦品种为材料，研究了拉参数、粉质参数、蛋白质品质、糊化参数等小麦品种籽粒品质与面条品质的关系；对比了中法小麦品种面条品质的差异，并对其形成原因进行了分析；探讨了试验原料、数据分析方法和试验方法等因素对试验结果的影响；探讨了用质构仪评价面条品质时的代表性品质指标。研究结果发现，45min时拉伸参数，稳定时间，沉淀值，加入酶活抑制剂时所测糊化参数可以做为评价中国小麦品种面条用面粉品质的订 依据；沉淀值可作为小麦品种选育过程中预测面条筋力的首选指标；由质构仪所测得的硬度和断裂能量可做为主要代表性指标分别反映面条的粘弹性和筋力特性。中国小麦品种的面条粘结性和煮制吸不率较大，最佳煮制时间和干物质失落率较小，干面条的抗弯强度和熟面条的硬度、咀嚼性和筋力较低。蛋白质质量和糊化特性较低是形成这种差距的主要原因。     

小麦品质性状与鲜湿面条品质指标关系的研究

对32个品种北方小麦的品质指标进行了测定分析,并进行了制作鲜湿面条实验,通过简单相关分析、多元回归分析与通径分析等统计方法分析了小麦的理化指标与鲜湿面条品质之间的关系.研究结果表明面条的蒸煮损失率、拉伸强度等指标与面条综合得分有很强的相关性,可以用来辅助综合得分来对面条进行品质评价;小麦粉的蛋白质指标和淀粉指标都对面条品质有很强的影响,要对面条品质进行研究,必须从这两个方面进行综合考虑.     

国产优质面条小麦品种筛选与品质研究

为了筛选出国产优质面条小麦品种,通过对种植在不同年份同一地块的不同小麦品种进行了RVA糊化特性的研究,经过多批次的品质分析及制面品质研究,筛选出了郑农16、豫麦47、温麦6号等3个国产优质面条小麦品种.其淀粉品质优良,制作出的面条品质较好,超过了我国优质面条小麦品种935031.     

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