不同糊化度留胚米粉理化性质和体外消化性研究

以留胚米为原料在螺杆转速为100 r/min,水分含量为30 %,挤压温度分别为70~150 ℃的条件下制备不同糊化度的留胚米粉,研究不同糊化度对留胚米粉的理化性质和体外消化特性的影响。结果表明：随着糊化度的增大,留胚米粉的蛋白质、脂肪、可溶性膳食纤维、总淀粉和直链淀粉含量显著下降(P<0.05);色度、粒径、吸水性指数、水溶性指数及膨胀度呈上升趋势,且差异显著(P<0.05);高糊化度留胚米粉与原留胚米粉相比峰值黏度、谷值黏度、最终黏度及回生值均显著降低(P<0. 05),消化性显著提高(P<0.05)。不同糊化度留胚米粉的理化性质和体外消化特性具有明显差异。     

内源性成分对低GI挂面消化特性的影响

为研究内源性成分对杂粮复配低升糖指数（glycemic index,GI）挂面消化特性的影响,首先制备了以荞麦、山药、高直链玉米淀粉、小麦粉为原料的杂粮复配挂面,测定得到其GI值为53.02;在此基础上,对杂粮复配挂面的原料粉进行脱除酚类、脂类、蛋白质类、膳食纤维类等内源性成分后再分别制备成挂面,进行体外模拟消化。研究内源性成分对于挂面的淀粉水解率、蛋白消化率、结肠发酵环节的影响及作用机理。结果表明,分离内源性成分后制备的挂面,它们的淀粉水解率均明显上升,且预估升糖指数（estimated glycemic index,eGI）：脱脂挂面（68.76）>脱蛋白挂面（67.94）>脱膳食纤维挂面（63.62）>脱酚挂面（60.16）>低GI挂面（53.02）;挂面的蛋白消化率：脱膳食纤维挂面（65.04%）>低GI挂面（33.71%）>脱酚挂面（17.55%）>脱脂挂面（6.61%）;相较于小麦挂面,杂粮复配低GI挂面中的抗性淀粉显著提升了结肠发酵环节中短链脂肪酸（shortchain fatty acids,SCFAs）的含量,有助于宿主的糖脂...     

直链淀粉、蛋白质及脂类对大米粉热特性的影响

利用差示扫描量热仪(DSC)分别对籼米、粳米、泰国香米及糯米米粉热特性作了研究。实验结果表明:直链淀粉、蛋白质及脂类对米粉糊化熔点、峰值、糊化终点温度及糊化焓变有重要影响。直链淀粉显著影响大米米粉的糊化熔点、峰值和终点温度,高直链淀粉含量的大米米粉的糊化熔点、峰值和终点温度均高于中、低及糯米米粉;高直链淀粉含量的大米蒸煮性差、能耗高、蒸煮时间长,中、低直链淀粉含量的大米蒸煮性好、能耗少、蒸煮时间短。米粉中的蛋白质可能起到升高米粉糊化熔点、峰值及终点温度的作用;大米蛋白质含量越高,大米蒸煮性越差、能耗越高、蒸煮时间越长。米粉中的脂类对米粉热特性的影响较复杂,脂类可能起到降低糊化熔点糊化焓变的效果;大米中脂类含量越高,大米蒸煮性好、能耗少、蒸煮时间短。     

挤压膨化处理对婴幼儿米粉理化和体外消化特性的影响

为探讨婴幼儿米粉基料干法制造过程中挤压膨化处理对米粉特性的影响规律,对不同品种大米经挤压膨化得到米粉的理化和消化特性差异进行比较分析,结果表明:在相同挤压膨化条件下,不同大米之间淀粉组成差异明显,导致膨化度、吸水指数和水溶性指数差异显著(P<0.05);处理后由淀粉体外消化特性得出:早籼米中抗性淀粉含量最高,接近15%;糯米快速消化淀粉含量最低,小于75%。蛋白质消化特性结果显示,糯米制品的胃蛋白酶消化率和蛋白质总消化率均低于其它3种米粉,这可能是因糯米中蛋白质的结构和组成不同所致。研究结果为挤压膨化技术在米粉生产中的应用及对不同品种大米米粉的性能影响提供理论依据。     

不同品种大米中蛋白质和脂肪对淀粉物化特性影响的研究

以湖北省9个品种的大米作为研究对象,通过对不同品种的大米全粉、脱脂米粉和脱蛋白米粉的物化特性进行比较,研究大米中蛋白质和脂肪对大米淀粉物化特性的影响。结果表明:不同品种大米中的基本物质含量有显著差异(P0.05);脱脂、脱蛋白对大米粉的透光率有较明显的影响;脂肪和蛋白质在大米中抑制了淀粉凝沉的进行,脂肪的抑制效果更明显;蛋白质对大米淀粉的膨润力、溶解度有抑制作用,脂肪对膨润力、溶解度也有小幅度的抑制作用,但没有蛋白质的作用明显;蛋白质对大米淀粉热特性的影响较大,与糊化焓变值呈负相关关系,脂肪对大米淀粉热特性影响较小,与糊化焓变值呈正相关关系;蛋白质阻碍了大米淀粉回生的过程,而脂肪对大米淀粉回生的过程没有影响;不同来源的大米脱脂、脱蛋白处理对淀粉物化特性的影响程度存在差异。     

烹制强度对米饭热力学及消化特性的影响

以三江大米(粳型)和星2号米(籼型)为原料,采用DSC、动态流变模拟米饭烹制过程,设置不同的烹制强度探究大米在烹制过程中的相态转变、热力学特性和米饭淀粉、蛋白质的消化性。结果表明,低强度的浸泡条件使米饭黏弹性较低,淀粉易于糊化,具有较高的淀粉和蛋白质消化率。高强度的烹制模式会提高米饭的黏弹质地和糊化程度,淀粉和蛋白质消化率较低。三江米饭的黏弹性与消化性之间存在负相关,星2号米饭的黏弹性与消化性之间的相关性不显著。同一烹制强度下,三江米饭的弹性大于星2号米饭,淀粉和蛋白质消化率小于星2号米饭。     

杂粮原料对其挂面淀粉消化性的影响及内在因素研究

本文以五种杂粮粉为原料,通过体外模拟消化试验研究了杂粮原料对其挂面体外淀粉消化特性和估计血糖生成指数（eGI）的影响。结果表明：杂粮挂面的eGI值由高到低为：大麦>青稞>苦荞>燕麦>高粱。采用差示扫描量热仪、傅里叶红外光谱仪和X射线衍射仪等手段分析了杂粮挂面淀粉理化特性差异。高粱糊化温度和焓值显著高于其他杂粮（P<0.05）;燕麦和高粱挂面直链淀粉含量和淀粉相对结晶度较高,且具有较多短程有序结构和较强氢键强度。采用组分分离法探究了内源性酚类物质和脂肪对挂面消化特性的影响,内源性多酚和脂肪的脱除使面条淀粉消化率明显升高。该研究为开发低GI食品提供了参考依据。     

可溶性大豆膳食纤维对糯米淀粉体外消化性的影响及其作用机制

以糯米淀粉为原料,研究可溶性大豆膳食纤维对其体外消化性的影响。结果表明,可溶性大豆膳食纤维的添加显著降低了糯米淀粉的体外消化率,添加量越多,效果越显著。可溶性大豆膳食纤维添加量为25%时,糯米淀粉的快消化淀粉含量从83.17%减少至68.90%,慢消化淀粉、抗性淀粉含量分别从11.57%、5.26%增加至18.12%、12.98%。可溶性大豆膳食纤维的添加可以阻碍水分子进入到淀粉内部,延缓糯米淀粉的糊化过程,降低糯米淀粉对消化酶的敏感性。傅里叶变换红外光谱分析结果显示,糯米淀粉和可溶性大豆膳食纤维间没有通过新的结合键相互作用。采用扫描电子显微镜观察到可溶性大豆膳食纤维对糯米淀粉有黏附包裹的作用,阻碍了消化酶的酶解作用。     

挤压对果蔬谷物早餐组分的变化研究

将大米粉、枣粉和胡萝卜粉按照80%∶12%∶8%的比例混合,用双螺杆挤压机进行挤压。研究挤压对维生素C、β-胡萝卜素和膳食纤维含量的影响,同时研究挤压前后淀粉、蛋白质性质的变化。结果表明,挤压以后维生素C和β-胡萝卜素的含量减少,但是可溶性膳食纤维和不溶性膳食纤维的含量均增加;通过扫描电镜发现,挤压会破坏淀粉颗粒,同时挤压会增加淀粉的糊化度、溶解度和消化率;挤压后水溶性、盐溶性、醇溶性和碱溶性蛋白质的含量分别减少了31.10%、38.88%、14.62%和64.64%,但是挤压提高了蛋白质的消化率。     

纤维对冰湖野米粉理化和消化特性的影响

目的 探究冰湖野米中内源纤维对冰湖野米粉的理化、功能和消化特性的影响。方法 以3种不同级的冰湖野米(长粒、中粒和短粒)和早籼米(对照)为原料, 将其研磨后过100目筛制备原米粉, 再采用焦亚硫酸钠法去除纤维制备去纤维米粉。利用扫描电镜和光学显微镜观察内源纤维对冰湖野米粉颗粒形貌的影响; 采用Brabender粘度仪测定内源纤维对冰湖野米粉的粘度特性的影响; 利用X射线衍射分析内源纤维对冰湖野米粉结晶特性的影响; 采用Englyst体外消化法评价内源纤维对冰湖野米粉消化性的影响。结果 不同颗粒长度的冰湖野米粉的形貌特征、结晶结构和粘度特性均无太大差异, 中粒冰湖野米粉慢消化淀粉含量最高, 短粒冰湖野米粉抗性淀粉含量最高。与早籼米相比, 冰湖野米粉起糊温度升高, 峰值粘度降低, 膨胀度降低, 快消化淀粉含量降低, 抗性淀粉含量升高。与原冰湖野米粉相比, 去除纤维后, 样品结晶度升高, 起糊温度降低, 峰值粘度升高, 膨胀度升高, 快消化淀粉含量升高, 抗性淀粉含量降低。结论 冰湖野米粉中内源纤维对冰湖野米粉粘度特性、结晶结构及消化性有显著的影响, 内源纤维的物理包埋以及与淀粉之间的相互作用, 会共同抑制淀粉颗粒的膨胀和糊化, 降低淀粉的消化酶解速率。     

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.     

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.