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1.
为了解γ-聚谷氨酸(γ-PGA)对小麦淀粉糊化及流变学特性的影响,采用快速黏度仪、差式扫描量热仪、流变仪、扫描电镜测定添加不同比例γ-PGA的小麦淀粉糊化特性、热力学性质、流变学特性、微观结构。结果表明,随γ-PGA添加量的增加,小麦淀粉糊的黏度、糊化焓值降低,糊化温度升高,γ-PGA阻碍了淀粉糊化,增强了淀粉糊的热稳定性;储能模量G′和损耗模量G″降低,损耗角正切tanδ升高,该混合体系为弱凝胶动态流变学图谱,弹性大于黏性;应力随添加量的增加而降低,呈剪切稀化现象,该淀粉糊为假塑性流体;γ-PGA使淀粉凝胶孔洞变小,微观结构更加致密。γ-PGA明显改善了小麦淀粉的糊化及流变学性质,添加量为0.7%时影响效果最大。  相似文献   

2.
小麦淀粉流变学特性分析   总被引:4,自引:0,他引:4  
研究小麦淀粉流变学特性,对小麦淀粉溶液糊化过程中粘度与剪切速率、温度和浓度关系进行分析,结果显示糊化后小麦淀粉糊为典型假塑性流体,对小麦淀粉糊流变学分析表明,其流变模型用幂函数表示有很高拟合度,以Y表示粘度,X表示剪切速率,浓度8%,90℃时,本实验小麦淀粉模型为y=1319.5x-0.4144,R2=0.9735。  相似文献   

3.
玉米淀粉磷酸酯糊特性研究   总被引:2,自引:0,他引:2  
以玉米淀粉为原料和三偏磷酸钠反应,并采用分光光度计、旋转粘度计等现代分析仪器,对生成的玉米淀粉磷酸酯的糊特性进行了较详细的研究,通过流变学分析,测得所得变性淀粉糊均为非牛顿流体。结果表明:交联度较高时,糊的透明度低,但冻融稳定性较好。  相似文献   

4.
为探索菊糖作为非淀粉多糖添加物对小麦淀粉的影响,以小麦淀粉为原料,采用差示扫描量热仪(DSC)、快速黏度分析仪(RVA)以及流变仪分析了不同添加量的菊糖对小麦淀粉糊化、回生以及流变学等特性的影响。试验结果显示:随着菊糖添加量的增加(0%~20%),复配体系的糊化温度不断升高,在4℃环境下贮藏一定时间后,其老化速率随着菊糖添加量的增加不断降低。静态剪切流变测试结果表明:复配体系黏度不断下降,其流变学特性均符合幂率模型,为假塑性流体;动态黏弹性测试结果表明不同菊糖添加量的淀粉凝胶均为弱凝胶。添加适量的菊糖不仅可以改善淀粉糊的糊化和流变特性、推迟淀粉糊的糊化时间,对淀粉的回生也有一定程度的抑制作用。  相似文献   

5.
利用快速黏度分析仪(RVA)、差示扫描量热仪(DSC)、流变仪(DHR)和扫描电镜(SEM)测定添加小麦纤维对小麦淀粉糊化特性、热力学特性、流变学特性和微观结构的影响。结果表明,随小麦纤维添加量的增加,小麦淀粉崩解值和回生值显著降低,表明小麦纤维抑制了小麦淀粉凝胶的老化;在4℃环境下储藏7d后,其老化焓值随小麦纤维添加量增加显著降低,抗老化性显著提升;添加不同浓度小麦纤维的淀粉糊为假塑性流体,小麦淀粉凝胶均为弱凝胶;小麦淀粉凝胶微观结构显示小麦纤维添加使小麦淀粉凝胶的表面更加完整、结构更加致密。由此表明小麦纤维对小麦淀粉凝胶老化有显著抑制作用。  相似文献   

6.
《粮食与油脂》2013,(8):8-12
为探索不同程度热损伤对小麦淀粉其颗粒特性与淀粉糊特性影响,以市售神象特一粉为原料,在室温、50℃和70℃温度处理下,分别测定小麦总淀粉、A–淀粉、B–淀粉破损淀粉含量、淀粉颗粒特性和淀粉糊特性变化;同时,该文探究热损伤对淀粉糊化特性影响,并表述该损伤方式损伤机理。  相似文献   

7.
青稞淀粉和小麦淀粉的理化性质比较研究   总被引:5,自引:1,他引:4  
研究了青稞淀粉的理化性质,包括淀粉的颗粒形态、粒度分布及淀粉糊透明度、溶解度、膨胀力和糊化特性,并与小麦淀粉性质进行比较。结果表明:青稞淀粉颗粒的平均粒径大于小麦淀粉颗粒的平均粒径,青稞淀粉颗粒大小和形状分布均匀;青稞淀粉糊透明度大于小麦淀粉糊,但在储藏过程中,青稞淀粉糊透光率变化显著;青稞淀粉的溶解度和膨胀力均大于小麦淀粉糊,这与小麦淀粉中小颗粒淀粉含量较多有关;与小麦淀粉的糊化相比,青稞淀粉成糊温度低,糊化容易,但峰值黏度低,衰减值大,热糊稳定性差,回生值大,冷糊稳定性差,易老化。  相似文献   

8.
为保持小麦淀粉天然特性,发展一种通过直接破碎浸泡过的小麦籽粒分离淀粉的方法,然后对所得十九种国内优质小麦的淀粉的蛋白质、脂肪、直链淀粉、水分含量及白度进行测定,通过比较、分析,总结得出不同品种小麦淀粉特性。  相似文献   

9.
研究小麦微孔淀粉的半干法制备及理化特性。考察了反应温度、加酶量、加水量、pH值、反应时间5个因素对制备微孔淀粉吸油率的影响。通过正交试验得到了半干法制备小麦微孔淀粉的最佳工艺参数,即:反应温度52℃、pH5.5、加水量30%、加酶量1 600U/g、反应时间12h,在该条件下制得的微孔淀粉的吸油率为17.2%。同时也考察了小麦微孔淀粉的理化特性,包括流变学特性、糊的透明度、冻融稳定性;结果表明,小麦微孔淀粉比天然淀粉具有优良的糊稳定性和冻融稳定性好,可为小麦微孔淀粉的工业化生产提供参考。  相似文献   

10.
板栗淀粉特性研究进展   总被引:8,自引:0,他引:8  
对板栗淀粉的颗粒特性,淀粉糊的流变学特性、粘度特性以及淀粉的加工特性等进行了详细介绍,从而为板栗的深加工提供理论依据。  相似文献   

11.
The influence of physicochemical properties of starches on expansion of‘keropok’was studied. Swelling power, solubility, and amylose leaching of a starch were dependent on the lipid and protein contents of the starch. The morphology of different starch granules used in‘keropok’gel was observed using scanning electron microscopy. The sizes of swollen starch granules in the gel were quantitatively measured by image analysis. The average length and width of swollen gelatinized sago and tapioca starch granules were significantly higher than that of wheat starch, and consequently, the linear expansion of‘keropok’with wheat starch was lower than those of‘keropok’made with tapioca or sago starches. Linear expansion was positively correlated to swelling power and solubility of the starch. Textural properties of‘keropok’gels with different starches were also measured and found to have correlation with linear expansion of the final products.  相似文献   

12.
为了得到超声波辅助提取油莎豆淀粉的最佳条件,以及油莎豆淀粉的理化特性,本文通过单因素和响应面试验研究提取油莎豆淀粉的最佳条件,通过扫描电镜分析、傅里叶红外变换分析、X射线衍射分析、DSC分析研究其理化特性。结果表明:最佳工艺条件为温度30 ℃、时间50 min、液料比15:1 mL/g、pH8,此条件下油莎豆淀粉提取率为92.22%±0.99%。将油莎豆淀粉与小麦淀粉等五种淀粉的理化特性对比发现:油莎豆淀粉颗粒较其它淀粉表面光滑,粒径范围与木薯淀粉、红薯淀粉、小麦淀粉相近,明显小于马铃薯淀粉,粒径范围2~15 μm,处于中小水平;油莎豆淀粉C-O和O-H拉伸程度较低,C-H的伸缩振动程度较低;油莎豆淀粉晶型与大多数谷物淀粉相似,属于A型淀粉;油莎豆淀粉在DSC实验中起始温度、峰值温度仅低于红薯淀粉,终止温度低于红薯淀粉和玉米淀粉。综上,油莎豆淀粉粒径相对较小,其属于A型淀粉,与B型淀粉相比不易发生水解,且其支链淀粉结构较多。  相似文献   

13.
Starch is the main component of wheat having a number of food and industrial applications. Thousands of cultivars/varieties of different wheat types and species differing in starch functionality (thermal, retrogradation, pasting and nutritional properties) are grown throughout the world. These properties are related to starch composition, morphology and structure, which vary with genetics, agronomic and environmental conditions. Starches from soft wheat contain high amounts of surface lipids and proteins and exhibit lower paste viscosity, whereas that from hard cultivars contain high proportion of small granules and amylose content but lower gelatinization temperature and enthalpy. Waxy starches exhibit higher‐percentage crystallinity, gelatinization temperatures, swelling power, paste viscosities and digestibility, but lower‐setback viscosity, rate of retrogradation and levels of starch lipids and proteins than normal and high‐amylose starches. Starches with high levels of lipids are less susceptible towards gelatinization, swelling and retrogradation and are good source of resistant starch, while that with high proportion of long amylopectin chains are more crystalline, gelatinize at high temperatures, increase paste viscosity, retrograde to a greater extent and decrease starch digestibility (high resistant and slowly digestible starch and low rapidly digestible starch).  相似文献   

14.
A comparison between the morphological, thermal, rheological and noodle‐making properties of corn starch and potato starches separated from five different potato cultivars was made. The granule size and shape of all starches differed significantly. Potato starch granules were comparatively larger than corn starch granules, while the transition temperatures were found to be higher for corn starch. Consistency coefficients and flow behaviour indices measured by back extrusion were higher for potato starches than for corn starch. Stickiness of cooked starch pastes was observed to depend upon their consistency coefficient. The gels made from all potato starches showed higher gel strength than those from corn starch. The gel strength of starches from both corn and potato increased during refrigerated storage. The amylose content, swelling power, solubility and light transmittance values of potato starches were significantly higher than those of corn starch. Noodles made from potato starches had higher cooked weight and cooking loss than corn starch noodles. Texture profile analysis revealed that potato starch noodles also had higher hardness and cohesiveness than corn starch noodles. Hardness of cooked noodles from all starches increased and cohesiveness decreased during storage. Noodles made from starches of higher viscosity exhibited higher hardness and cohesiveness. Textural differences among cooked starch noodles appeared to be associated with morphological, thermal and rheological properties of corn starch and potato starches. © 2002 Society of Chemical Industry  相似文献   

15.
Volatile compounds of wheat, corn, and potato starches were determined prior to and upon extraction of the starches with aqueous solutions of sodium hydroxide (NaOH), ethanol, and sodium dodecyl sulfate (SDS). Aqueous NaOH extraction was effective in reducing the level of total volatiles and removing certain volatiles from both wheat and corn starches without increasing the level of hexanal, an important lipid autoxidation product. However, the extraction did not considerably influence the composition and abundance of volatiles in potato starch. Aqueous ethanol extraction reduced the level of total volatiles only in wheat starch. Aqueous SDS extraction was not practical in the removal of volatiles from cereal starches. However, SDS extraction was effective in removing volatiles from potato starch, as well as reducing its hexanal level. It is evident that NaOH extraction is suitable for the removal of volatiles associated with cereal starches, whereas SDS extraction is more appropriate for tuber starches.  相似文献   

16.
The lipid constituents from wheat, corn and potato starches were analyzed, as was the composition of nonstarch compounds present in these lipid extracts. The lipids were extracted from starch granules using n- propanol-water (3:1, v/v) via cold and hot extraction into surface and internal lipid fractions, respectively; fatty acid profiles of the fractions so obtained were then carried out. The content of surface lipids was greatest from potato and wheat starches, whereas cornstarch was characterized as having the highest relative percentage of internal lipids. Hot extraction resulted in an increase in the lipid content for all extracts, and of the starches investigated, the lipids from cornstarch contained the highest percentage of polyunsaturated fatty acids. Unlike that of wheat starch, it was noted that the fatty acid, C20: 1 (n-9), could only be extracted from corn and potato starch granules by the hot extraction technique. Lysophosphatidylcholine (LPC) and some phenolics were found to bind to wheat starch granules, but not to those of corn and potato. Using HPLC-UV-DAD analysis, five phenolic compounds were detected in the lipids extracted from wheat starch by hot extraction. Maxima from UV-DAD spectra of the compounds were observed at a wavelength of 337.4 or 332.7 nm, and are characteristic of phenolic acids or their derivatives.  相似文献   

17.
脱脂脱蛋白处理对小麦A、B淀粉理化性质的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
为阐明脂类和颗粒结合蛋白对小麦A、B淀粉理化和结构性质的影响,以豫麦49-198为试验材料,采用面团法制备小麦淀粉,沉降法分离小麦A、B淀粉,并对其进行脱脂脱蛋白处理,研究了处理前后小麦A、B淀粉组成、颗粒结构、溶解度与膨胀度、糊特性、热特性等性质的差异。结果表明:与未处理的小麦A、B淀粉相比,脱脂脱蛋白处理后小麦A、B淀粉颗粒表面较光滑,分散程度较均匀,偏光十字的位置和形状无显著性差异,清晰度显著增加;溶解度和膨胀度随温度的增长趋势显著增加;起始温度、峰值温度、终值温度、透明度、峰值黏度、衰减值、回生值显著增加;冻融稳定性、峰值时间显著降低;热焓值无显著变化。这为小麦A、B淀粉更好的应用提供理论参考。  相似文献   

18.
Physiochemical and Rheological Characterization of Sorghum Starch   总被引:2,自引:0,他引:2  
Starch was isolated from the seeds of 3 sorghum cultivars and compared with commercial wheat starch. The amylose content of sorghum starches was in the range of 22.0–27.8%. Sorghum starches had less total lipids than wheat starch (1.66%) but there was no difference between sorghum Milo and Sorghum “100”. The water binding capacity of sorghum Dabar did not differ from that of wheat (100%) whereas differences in swelling power were observed, over a range of temperatures, between wheat and sorghum starches except for Sorghum “100” at 70°C. Sorghum starches showed single-step viscoamylographic curves with pronounced pasting peaks, good pasting stability and good set-back on cooling.  相似文献   

19.
不同来源的淀粉制备淀粉磷酸单酯的性能及应用   总被引:4,自引:0,他引:4  
本文比较了马铃薯淀粉、蜡质玉米淀粉、木薯淀粉、小麦淀粉及经磷酸化后产品的物理性能,着重研究了其粘度及糖、盐对其粘度的影响并比较了磷酸化对糊的透明度、冻融稳定性及其对发泡体系的影响,结果表明不同淀粉制得的淀粉磷酸单酯的性能有很大差别。在蛋糕中的应用试验表明,在蛋糕中添加淀粉磷酸单酯可以增加比容并延长其货架寿命。  相似文献   

20.
10种淀粉的理化特性研究   总被引:3,自引:1,他引:2  
通过对10种植物淀粉糊透明度、凝沉性、冻融性、流变性的理化特性研究,结果表明:薯类淀粉相对于其他类的淀粉糊具有更高的透明性、较低的凝沉比和黏度。加糖加盐对不同淀粉糊有不同的凝沉作用。相对于其他淀粉,玉米、糯米、高粱和小麦淀粉的析水率较低,有较好的冻融性。高粱淀粉、绿豆淀粉,马铃薯淀粉、藕粉淀粉、木薯淀粉黏度均随着剪切速率的增加而明显剪切稀化,呈典型的假塑性流体特性和具有触变性。高粱淀粉、绿豆淀粉有较高的黏性。高粱、小麦、糯米淀粉糊不耐酸性,而红薯、马铃薯、绿豆、藕粉、木薯淀粉糊相对来说比较耐酸性。所有类型的淀粉糊随着pH增加黏度有渐增趋势。  相似文献   

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