两种干燥方式对马铃薯全粉营养品质和加工特性的影响

以新鲜"云薯304"切片后,采用漂烫冻干、不漂烫冻干、漂烫烘干和不漂烫烘干四种工艺条件制备干片,再经研磨粉碎制成半生的马铃薯全粉,研究不同工艺条件下全粉的营养品质和加工特性。结果表明:采用漂烫冻干工艺,马铃薯全粉的颜色与鲜马铃薯颜色最接近,制备的马铃薯全粉还原糖含量最低,为0.15%;蛋白质含量(9.01%)、总淀粉含量(69.12%)、直链淀粉含量(31.60%)与其他三种工艺处理无显著差异;从加工特性上看马铃薯全粉的持水力(5.27 g水/g全粉)和持油力(1.55 g油/g全粉)、透光率(83.43%)和各个温度下的膨胀度(50℃:9.32 g/g;60℃:11.98 g/g;70℃:13.11 g/g;80℃:15.35 g/g;90℃:12.50 g/g)均最高,都显著高于其他三种工艺(P<0.05);且凝胶流程最短,为10.96 mm。因此,可认为漂烫冻干是制备马铃薯全粉的最优工艺。     

甘薯生全粉对面团特性及馒头品质的影响

该实验以甘薯-小麦混粉为原料,探究甘薯生全粉添加量对混粉特性、混粉面团特性以及甘薯生全粉馒头综合品质影响的研究。结果表明,甘薯生全粉中主要成分为淀粉,含量约为64.60%;随着混粉中甘薯生全粉含量的增加,混粉的持水性从1.16 g/g增加至1.70 g/g,持油性呈先增大后减小的变化趋势。随着甘薯生全粉添加量增大,混粉粉质特性变差,面团加工品质降低;随着混粉面团中甘薯生全粉含量的增加,面团的TO、TP、TC、硬度逐渐增大,弹性逐渐减小;甘薯生全粉添加量在20%以内时,甘薯馒头感官评分大于70,馒头的质构、比容和白度仍在可接受范围内。综上所述,当甘薯生全粉添加量小于10%时,混合面团的加工特性和馒头品质较优;当甘薯生全粉添加量小于20wt%时,混合面团的加工特性和馒头品质在可接受范围内。     

‘黑美人’马铃薯颗粒全粉品质特性分析

为开发‘黑美人’马铃薯特色食品,对比分析了‘黑美人’马铃薯颗粒全粉和‘陇薯7’号马铃薯颗粒全粉的蛋白质、淀粉、维生素C、灰分、花青素含量及氨基酸构成等营养品质指标,色泽、碘蓝值、持水率、持油率、析水率、溶解度、膨胀度、沉淀指数、最低胶凝浓度等理化和加工特性。结果表明,‘黑美人’马铃薯颗粒全粉蛋白质含量(10.23%)、维生素C含量(7.95 mg/100 g)和必需氨基酸与氨基酸总量比值(47.20%)等营养品质指标,持水率(5.65 g/g)、持油率(3.023 g/g)、膨胀度(14.48%)和沉淀指数(38.83 mL)等加工特性指标均高于‘陇薯7号’马铃薯颗粒全粉,且差异显著(P0.05)。‘黑美人’马铃薯颗粒全粉还含有丰富的花青素,含量达到342.06 mg/100 g,花青素保持率83.72%,全粉与原料色泽非常接近,花青素保持良好。‘黑美人’马铃薯颗粒全粉比普通马铃薯颗粒全粉营养价值更高,食品加工性能更优,具有广阔的开发利用前景。     

马铃薯全粉剂量效应对面团特性以及馒头品质作用分析

为丰富馒头营养和品种,向面团中加入马铃薯全粉,分析马铃薯全粉基本成分及物化特性,探究马铃薯全粉剂量效应对混粉、面团特性,以及馒头品质影响的研究。结果表明,马铃薯全粉中主要成分为淀粉,含量约为67.07%;马铃薯全粉的持水性、吸水膨胀性分别为3.57 g/g、2.49 mL/g;马铃薯全粉的粘度为12.71 m2/s,与面粉混合可以增强面团的物化特性。马铃薯全粉的添加使得面团粉质特性变差,揉混特性变好,添加量为8%~15%时,面团糊化特性和拉伸特性较好;随着马铃薯全粉添加量的增加,马铃薯馒头表皮、内瓤白度降低;马铃薯全粉添加量为5%~8%时,馒头比容、硬度、胶着性和咀嚼性较大,感官评分高。综上所述,为提高面团特性,马铃薯全粉的建议添加量为8%~15%;为改善馒头品质,马铃薯全粉的建议添加量为5%~8%。     

不同品种甘薯全粉品质特性比较

对比分析19个不同品种甘薯全粉的营养品质与物化特性,结果显示,19种甘薯全粉可筛分为7类,其中营养品质最好的前三品种为Q7007>赣紫C702>宁紫8号。聚类分析显示,根据各品种性能相似,可将其划分4个大类,Ⅰ类：7个品种,持水、吸水膨胀力中等,持油力低;Ⅱ类：3个品种,持水力高,持油力低;Ⅲ类：5个品种,持水、持油和吸水膨胀力均较低;Ⅳ类：4个品种,持油和吸水膨胀力高。此外,糊化起始温度(To)、峰值温度（Tp）、终止温度（Tc）、热焓（ΔH）分别介于73.47 ℃~83.00 ℃、80.63~88.10 ℃、86.87~92.90 ℃、0.79~3.77 J/g之间,To、Tp、Tc最高的是徐薯22,最低的是苏薯32。相关性分析显示,蛋白质含量与吸水膨胀性呈显著负相关,持水性与持油性分别与花青素、β-胡萝卜素含量呈显著正相关,证明甘薯全粉的营养品质与物化特性之间存在着紧密联系。因此,可根据不同品种甘薯全粉的营养品质、物化特性及性状相关对其进行加工利用,以期为甘薯资源的推广和产品开发提供理论依据。     

紫薯-低筋复配粉理化特性及其饼干制品品质分析

研究紫薯全粉不同添加量对低筋粉加工特性,及其饼干制品品质的影响。结果表明,紫薯全粉-低筋粉复配处理后,相较于低筋粉,10%～50%复配粉的持水性提高了0.90～2.08 g/g,持油性降低了0.05～0.18 g/g。随着紫薯全粉比例的增大,低筋粉的糊化起始温度(T_o)、峰值温度(T_p)、终止温度(T_c)逐渐升高,而热焓值(ΔH)逐渐减小,紫薯全粉的T_o、T_p、T_c则呈下降趋势,ΔH呈上升趋势。紫薯全粉的加入导致面团面筋膜撕裂,黏着性变差,当添加量达到50%时,复配粉基本不具备面筋网络形成能力,由其制成的饼干硬度和脆性相较于对照组分别降低2 276.49 g、5.43 mm,而抗性淀粉含量提高了8.42 g/100 g。10%～30%紫薯全粉添加量有利于饼干感官品质的提升,其可接受度程度依次为30%紫薯饼干>20%紫薯饼干>10%紫薯饼干。     

微波热处理对马铃薯全粉品质改良及马铃薯面包消化特性的影响

采用微波热处理对马铃薯全粉进行改良,明确马铃薯脂肪酶、持水力、不溶性膳食纤维及粉质特性的变化规律。将改良后的马铃薯全粉与高筋粉按3:7比例制作马铃薯面包,研究不同微波功率对马铃薯面包品质及淀粉消化特性的影响规律。结果表明:微波热处理后的马铃薯全粉各项特性均得到改善,随着微波功率的增加,马铃薯全粉脂肪酶残余酶活降至1.23%,持水力提升至5.71 g/g,不溶性膳食纤维含量降低了21.35%。与未经微波热处理的马铃薯全粉制成的马铃薯面包相比,改良后的马铃薯面包营养及消化特性均得到了明显的改善,当微波功率为750 W时面包各项指标最优,比容提升为4.04 mL/g,硬度降为115.50 g、弹性升高为9.17 mm,抗性淀粉含量提高为43.60%,HI_WB750、PGI_WB750分别降低为67.29%、46.34,改良后的马铃薯面包抗老化能力和感官品质均有所提升。     

辽宁省主栽品种马铃薯块茎和马铃薯全粉的品质分析

以辽宁省主栽的11个品种马铃薯块茎为原料,采用捣碎制泥工艺生产马铃薯颗粒全粉,测定其原料品质指标(总淀粉、蛋白质、还原糖、脂肪、粗纤维和氨基酸)和颗粒全粉功能性指标(碘蓝值、透光率、冻融稳定性、持水和持油性)。结果表明:11个马铃薯品种的淀粉含量为67.9%~73.4%,其中大西洋、919淀粉含量高,早大白和克23淀粉含量低;蛋白质含量差异较大,其中富金、尤金蛋白质含量高,中5蛋白质含量最低;还原糖含量差异也较大,BQ25和大西洋含量较低,克23还原糖含量较高;脂肪含量差异不大;大西洋粗纤维含量较低,克23粗纤维含量较高。异亮氨基酸、苯丙氨基酸+酪氨酸含量11个品种均高于世界卫生组织(WHO)的“必需氨基酸模式标准”,相对其他氨基酸,33、大西洋、夏波蒂和中5的氨基酸含量较高。11种马铃薯全粉的游离淀粉率差异不大。但是透光率差异很大,919的透光率最大,BQ25和大西洋的透光率较小。富金、克23和33的析水率较高,BQ25和大西洋析水率低。11种马铃薯全粉的持水能力为7.3~8.1 g/mL,持油能力为7.6~8.6 g/mL。     

紫色马铃薯全粉蛋糕的研制

通过单因素试验和正交试验确定了紫色马铃薯全粉蛋糕的最佳配方为:小麦面粉与紫色马铃薯全粉质量比为3∶2,其中紫色马铃薯全粉40g、小麦面粉60g、鸡蛋360g、黄油50g、白糖80g、植物油40g、盐2g、泡打粉1g、塔塔粉1g。烘烤温度:上火180℃、下火180℃、烘烤时间30min。该方法加工的紫色马铃薯全粉蛋糕具有独特的马铃薯风味,薯香浓郁、口感润泽、无甜腻感、内部组织细腻、松软有弹性、感观品质和质构特性优良。紫色马铃薯全粉蛋糕开发了紫色马铃薯主食化的新途径,既提高了传统蛋糕的营养价值,又增加了蛋糕的花色品种,具有良好的市场前景。     

挤压处理对马铃薯全粉加工特性及微观结构的影响

采用挤压法对马铃薯全粉进行挤压处理,考察挤压温度、物料水分质量分数对马铃薯全粉加工特性及马铃 薯全粉面团弹性的影响,通过单因素试验确定最佳挤压工艺参数,采用扫描电子显微镜、差示扫描量热仪、快速黏 度测定仪、X射线衍射仪等仪器,对挤压处理前后马铃薯全粉的微观结构、热力学性质、糊化特性及结晶度变化等 进行对比分析。结果表明：当挤压温度为150 ℃、物料水分质量分数为35%时,马铃薯全粉的加工特性综合比较最 优,溶解度较高,持水性最好,冻融稳定性较好,此时马铃薯全粉面团弹性最好;挤压处理后的马铃薯全粉表面微 观结构出现褶皱,比表面积增加;热稳定性减弱,凝胶性减弱,不易回生;挤压处理使马铃薯全粉的结晶度下降。     

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