芋艿头全粉对富硒芋艿头营养重组米结构及特性的影响

以芋艿头全粉和碎粳米为主要原料,硒作为营养强化剂,L-α-磷脂酰胆碱和单甘酯作为复合质构调节剂,利用挤压膨化法制备富硒芋艿头营养重组米。通过对芋艿营养重组米研究发现:芋艿头全粉可提高营养重组米的黏聚性,增加营养重组米的弹性,改善营养重组米的硬度和感官品质;营养重组米表面粗糙呈不规则形状,形成了V-型淀粉酯复合物的结晶结构,相对结晶度降低,糊化温度降低,淀粉酯复合物的焓变值增大;营养重组米的峰值黏度、衰减值和回生值均逐渐减小,快消化淀粉含量降低、慢消化淀粉和抗性淀粉含量升高,富硒芋艿头营养重组米的稳定性、抗老化性和消化特性得到明显改善。该研究结果可为开发功能型营养重组米提供理论支撑。     

粳米重组米的制备工艺优化及性能研究

以碎粳米粉为原料,添加一定量的抗性粳米淀粉,采用双螺杆挤压技术制备重组米,考察了模头温度、水分含量和螺杆转速对重组米品质的影响。在单因素基础上,采用响应面优化了挤压工艺条件,测定了重组米的糊化、流变、蒸煮和消化性能。结果表明,当模头温度100℃、水分含量28%、螺杆转速96 r/min时,重组米的综合得分达到70.7±0.5。重组米糊化特性的各项指标均低于市售粳米,而黏度、回生值和糊化温度略高于空白重组米;重组米G’、G"低于市售粳米,略高于空白重组米;重组米的吸水率、体积膨胀率和蒸煮损失率均高于空白重组米和市售粳米;相比于空白重组米和市售粳米,重组米的SDS和RS含量较高,RDS含量较低,分别为51.62%、9.37%和39.01%。本研究结果可为低消化性重组米产品的开发提供实验依据。     

莲子淀粉重组米制备工艺优化

以不同比例莲子淀粉与碎米粉进行混合后挤压制备重组米,通过对混合粉的糊化特性和重组米的感官品质、质构特性及蒸煮损失率的分析,确定了莲子淀粉重组米的配比。以物料含水量、模头温度、螺杆转速为影响因素,采用响应面试验优化了莲子淀粉重组米挤压的最佳工艺条件。结果表明:随着莲子淀粉添加量的增加,混合粉的峰值黏度、谷值黏度、崩解值、最终黏度及回生值等均逐渐增加;感官评分先增大后减小,在莲子淀粉添加量为30%时较高;质构特性中硬度逐渐增大,弹性、咀嚼性、黏聚性先增大后减小,在莲子淀粉添加量为30%时最大;蒸煮损失率逐渐增大。综合分析,重组米品质在莲子淀粉添加量为30%时达到最佳。重组米的最佳挤压条件为:物料含水量40%、螺杆转速210 r/min、模头温度95 ℃时,重组米评分为69.13分。     

低GI挤压重组米配方优化及食用品质评价

采用双螺杆挤压法,以大米粉为基料,配比一定量的酸改性淀粉、抗性糊精、魔芋粉、聚甘油酯,探究制备低血糖生成指数(glycemic index,GI)重组米优化配方.体外消化法测定挤压重组米GI值,通过感官、质构、蒸煮品质综合评价低GI重组米的食用品质,使用扫描电镜观察微观形貌.结果显示,添加量为大米粉60％、酸改性淀粉3...     

挤压生产糙米重组米的研究

本文以籼糙米为原料,采用双螺杆挤压技术制备糙米重组米,对制备工艺进行了优化,同时研究了挤压参数及干燥条件对糙米重组米品质的影响。研究结果表明,最佳挤压工艺参数为:3、4区挤压温度100℃,加水量28%(原料初始水分含量为12%),螺杆转速100 r/min。提高干燥温度会对产品的质构、蒸煮品质和色泽产生不利影响,最佳干燥条件为45℃下干燥105 min。在该优化条件下制备的糙米重组米米饭的挥发性风味成分与糙米米饭存在差异,糙米重组米风味成分组成及含量总体较好;糙米重组米的硬度和粘附性接近于白米,质构及蒸煮品质均优于糙米,并且与市售重组米无显著差异(p0.05)。     

挤压膨化与重组造粒茯苓复配谷物产品功能成分分析及淀粉体外消化特性评价

以茯苓与谷物复配制得的营养粉及重组米为研究对象,探究挤压膨化及重组造粒对产品营养功能成分和碳水化合物体外消化特性(预期血糖反应)的影响。结果表明,挤压膨化比重组造粒更易导致红米多酚和苦荞黄酮损失,两种加工方式对薏苡仁酯及茯苓三萜酸含量的影响均不显著(P0.05),但可改善茯苓多糖水溶性,产品中茯苓水溶性多糖含量增加率达52.57%～61.08%;与谷物原料相比,产品的快消化淀粉和抗性淀粉含量分别增加6.79%～24.12%和14.97%～43.30%,而慢消化淀粉含量减少21.73%～41.44%;添加20%的茯苓对产品快消化、慢消化、抗性淀粉含量均无显著影响(P0.05),但对淀粉水解指数(HI)和血糖负荷评估值(EGL)影响显著(P0.05),分别降低16.81%～18.40%和32.42%～36.63%,食用后可维持餐后血糖稳态化,血糖负荷较小。     

挤压碎米制备富锌强化大米

以粳米加工副产品碎米为原料,使用乳酸锌作为锌强化剂,通过挤压法制备富锌强化大米。将碎米粉碎成100?目,乳酸锌添加量2.0%,采用响应面法考察含水量、螺杆转速及机筒温度对富锌强化大米质构特性的影响。优化条件为含水量20%、螺杆转速80?r/min、机筒温度100?℃,制得富锌强化大米硬度为1?339.05?g,黏着性为0.75?mJ,弹性为0.79?mm,咀嚼性为967.42?mJ,锌含量为450.0?mg/kg。经X-射线衍射分析表明强化米中淀粉颗粒的结晶度较粳米明显减少,通过扫描电镜表征发现强化米淀粉颗粒外表面呈现不规则类似鳞片形状,并产生聚集现象,淀粉糊化温度由77.9?℃降低到56.2?℃,酶解反应完成后还原糖增加23.0%以上,有利于强化米淀粉颗粒的酶解作用。将其按1∶10的比例添加到粳米中,米饭口感、外观良好,锌含量为48.0?mg/kg。     

马铃薯全粉-碎米混合粉的糊化特性及其挤压重组米品质

将马铃薯全粉与碎米按不同比例混合,测定混合粉的糊化特性及其挤压重组米的感官品质、质构特性和蒸煮损失率,探讨马铃薯全粉添加量对混合粉糊化特性及其挤压重组米品质的影响。结果表明:随着马铃薯全粉添加量的增加,马铃薯全粉-碎米混合粉的峰值黏度、谷值黏度、最终黏度、衰减值和回生值均逐渐减小;马铃薯挤压重组米的感官评分先增大后减小,在添加量为40%~50%时较高;质构特性中硬度显著(p<0.05)减小,弹性、黏聚性、咀嚼性先增大后减小,在添加量为50%时最大;蒸煮损失率显著(p<0.05)增大。结合感官品质、质构特性、蒸煮损失率结果,马铃薯全粉添加量≤50%时,加工出的马铃薯挤压重组米品质较好。马铃薯全粉的添加量、马铃薯全粉-碎米混合粉糊化特性与马铃薯挤压重组米品质特性存在显著(p<0.05)相关性。     

抗性淀粉对复合营养强化米质构和品质的影响

精选五谷杂粮为原料,抗性淀粉作为主料,采用双螺杆挤压工艺,根据其营养成分和食品加工学特性,调节配方和比例混合配比,研究抗性淀粉添加量对复合营养强化米品质效果的影响。结果显示,当抗性淀粉添加量为55%时,复合营养强化米断面比较平整;加热吸水率和膨胀率最大,分别为282%、272%,可溶性固形物含量最低,蒸煮品质较优;质构特征最佳,硬度、弹性、黏聚性、胶着度、咀嚼度、回复性值分别为869.159 g、0.891 mm、0.473 g·s、546.458 g、536.389 g及0.106 g·s;感官评价最优。综合各种测定指标结果显示,抗性淀粉含量在55%时复合营养强化米品质最优。     

螺杆挤压对马铃薯淀粉消化性及血糖指数的影响

目的研究螺杆挤压对马铃薯淀粉消化特性的影响。方法马铃薯淀粉经过螺杆挤压后(过程中淀粉未膨化),采用酶重量法测定挤压后抗性淀粉的含量变化情况,并通过模拟体外消化和动物实验评价挤压后淀粉的消化性能和餐后血糖上升速率。结果螺杆挤压后马铃薯淀粉中抗性淀粉的含量增加了1.08%,酶解时间为0~1.5 h时,马铃薯淀粉快速消化淀粉的含量减少,酶解时间为1.5~6.5 h时,抗性淀粉和慢消化淀粉的含量增加。挤压后的马铃薯淀粉在一定程度上可以降低小鼠的餐后血糖指数。结论螺杆挤压技术可以提高抗性淀粉和慢消化淀粉的含量,减缓餐后血糖上升速率,为马铃薯食品的深度开发提供一定的参考。     

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