粉葛直链淀粉与支链淀粉分离工艺研究

以粉葛为原料,对粉葛中直链淀粉和支链淀粉的分离工艺进行了研究。根据直链和支链淀粉的理化特性及结构的不同,采用正丁醇-异戊醇配合物沉淀法对粉葛直链和支链淀粉进行粗分离,再经正丁醇重结晶得到较纯的直链与支链淀粉,讨论了分离前对淀粉进行预处理、纯化次数、分离过程中离心时间对分离效果的影响。通过对淀粉-碘复合物光吸收特性分析和蓝值比较,表征分离得到的直链与支链淀粉的纯度。结果表明:直链淀粉纯化5次、支链淀粉纯化6次、分离前经过预处理、支链淀粉纯化时离心时间和速度为30min,5 000r/min的条件下,光谱分析测得的最大吸收波长和蓝值都落在直链淀粉与支链淀粉文献报道结果的相应数值范围内,表明此时分离效果最佳,正丁醇结晶法分离的直链和支链淀粉纯度较高。     

双波长法测定木薯淀粉中直链和支链淀粉的含量

目的：分离纯化木薯淀粉中的直链和支链淀粉,建立同时测定木薯淀粉中直链与支链淀粉含量的双波长法。方法：采用正丁醇结晶法分离纯化直链和支链淀粉,蓝值比较法表征直链与支链淀粉的纯度;根据双波长法原理,分别在测定波长624、538nm,参比波长440、750nm处测定木薯淀粉中直链与支链淀粉含量。结果：分离纯化得到的直链与支链淀粉蓝值分别为0.979和0.144,分别落在0.8～1.2与0.08～0.22范围内,表明纯化后木薯直链与支链淀粉的纯度较高;直链淀粉在0～80mg/L质量浓度范围内其碘复合物与吸光度呈线性关系(r＝0.9992),支链淀粉在0～220mg/L质量浓度范围内其碘复合物与吸光度呈线性关系(r＝0.9995)。结论：正丁醇结晶法能有效地分离木薯直链与支链淀粉;双波长法操作快速、准确,无需分离即可同时测定木薯淀粉样品中直链和支链淀粉含量。     

番薯淀粉组分的分级分离

运用交联明胶亲和色谱法,对番薯淀粉组分进行分离,得到直链和支链淀粉两个级分。直链和支链淀粉级分的蓝值和β-淀粉酶酶解极限分别为1．38％和98％,0．20％和50％,与标准的直链和支链淀粉相当。番薯淀粉中直链淀粉级分的含量为15．6％。     

双波长法测定南瓜中直链与支链淀粉含量

为建立同时测定南瓜中直链和支链淀粉的双波长比色法。本文采用正丁醇结晶法分离纯化南瓜中直链和支链淀粉并测定其含量。结果表明,分离纯化得到的直链和支链淀粉蓝值分别为0.874和0.196;根据双波长原理和扫描谱图,确定其测定波长为645、565 nm,参比波长为495、730 nm处测定南瓜中直链与支链淀粉含量;南瓜样品中直链淀粉占21.64%,支链淀粉占50.19%,总淀粉含量为71.83%,相对标准偏差分别为0.97%和1.06%,平均回收率分别为98.62%和99.42%,检出限分别为0.0116和0.0644 mg/mL。正丁醇结晶法能有效地分离南瓜直链与支链淀粉,双波长法可同时获得南瓜中3个淀粉含量指标,该方法既节省了样品,又提高了效率。同时,该方法的建立也为南瓜淀粉理化特性的研究提供了技术支持。     

葛根直链淀粉和支链淀粉分离纯化的研究

用重结晶的方法对葛根淀粉中直链淀粉和支链淀粉组分进行分离和纯化，并利用碘亲和力测定，凝胶过滤层析，Ｘ－射线衍射等方法对产品的纯度进行了鉴定。结果表明通过重结晶８次可得到完全纯化的葛根直链淀粉；反复３次加入正丁醇去除残留的直链淀粉可得到完全纯化的葛根支链淀粉。     

芭蕉芋直链和支链淀粉纯品的提取及其光谱分析

分离提纯芭蕉芋淀粉中的直、支链淀粉,表征其纯度,建立快速测定芭蕉芋淀粉中直链淀粉含量的双波长法。正丁醇结晶法分离纯化直、支链淀粉;光吸收特性分析法表征直、支链淀粉纯度;根据双波长法原理,在测定波长617nm,参比波长504nm处测定芭蕉芋淀粉中直链淀粉含量。分离提纯得到的直、支链淀粉最大吸收波长分别为630～645nm和548～554nm,蓝值分别为1.167±0.209和0.122±0.001,均处于相应分布范围,表明提纯后直、支链淀粉的纯度较高;直链淀粉在0～80mg/L浓度范围内与吸光度呈线性关系,r=0.9998。正丁醇结晶法能有效地分离纯化芭蕉芋直、支链淀粉;光吸收特性分析法可有效地表征直、支链淀粉纯度;双波长法操作简便、准确,无需分离即可快速测定芭蕉芋淀粉中直链淀粉含量。     

双波长分光光度法测定高粱中的直链淀粉和支链淀粉

直链淀粉和支链淀粉含量及其比例是高粱品质的重要指标。高粱是酿酒的主要原料之一,高粱品质的检测具有十分重要的意义。为此需要寻找一种快速、简便、准确测量高粱中直链淀粉、支链淀粉、淀粉含量的方法。文中以GB7648-87为基础,研究出一种运用双波长测定高粱中直链淀粉和支链淀粉含量的新方法。结果表明,新方法准确性高、重复性好、效率高,工作量小,适于批量分析。     

双波长分光光度法测定高粱中的直链淀粉和支链淀粉

直链淀粉和支链淀粉含量及其比例是高粱品质的重要指标.高粱是酿酒的主要原料之一,高粱品质的检测具有十分重要的意义.为此需要寻找一种快速、简便、准确测量高粱中直链淀粉、支链淀粉、淀粉含量的方法.文中以GB7648-87为基础,研究出一种运用双波长测定高粱中直链淀粉和支链淀粉含量的新方法.结果表明,新方法准确性高、重复性好、效率高,工作量小,适于批量分析.     

荧光光谱法测定淀粉中的直链淀粉

为了建立一种荧光光谱法测定淀粉中直链淀粉含量的方法,采用荧光光谱法测定了直链淀粉的激发光谱和发射光谱以及直链淀粉与支链淀粉的浓度比对荧光强度的影响。结果表明:直链淀粉的激发波长为370 nm、发射波长为422 nm;在0.10~0.70 μg/mL浓度范围内,直链淀粉荧光强度与其浓度呈良好线性关系,相关系数r=0.9996,检出限为0.026 μg/mL。用该方法测定玉米淀粉和土豆淀粉中直链淀粉的含量,加标回收率为94.5%~121.7%,相对标准偏差(RSD)为2.42%~3.24%。该方法不需加任何生化试剂,不受时间、温度、共存支链淀粉的影响,快速简便,绿色环保,检出限低,结果准确。     

葛根淀粉提取及直链、支链淀粉的双波长测定

以淀粉提取率为指标,采用正交实验研究了葛根淀粉的加工工艺,并确定了最佳工艺参数为:料水比为2:17,浸泡液的pH为8.5,浸泡时间为1h;同时采用双波长分光光度法对葛根中直链淀粉和支链淀粉的显色反应和光度测定的最佳条件进行了详细的考察,根据吸收光谱,确定直链淀粉的测定波长为617nm和476nm,支链淀粉的测定波长为415nm和532nm,建立回归方程并求得葛根淀粉中直链淀粉的含量为18.29%,支链淀粉的含量为77.24%.     

Effect of phosphoric acid treatment on physicochemical,functional, and structural properties of starch extracted from yam (Dioscorea rotundata)

This work was designed to elucidate selected physicochemical, functional, and structural properties of native and modified yam (Dioscorea rotundata) starch. The isolated starch was chemically modified using 5, 10, 15, 20, and 25% phosphoric acid solution at 50°C for 1 h, and yield, swelling power, gelation, water holding capacity, paste clarity, blue value, and amylose and amylopectin content of the native and modified yam starch were determined. Structural changes in the native and starch modified with 25% phosphoric acid were evaluated using Fourier transform infrared spectroscopy and optical microscopy. The result showed that the yield, swelling power, water holding capacity, paste clarity, blue value and amylose and amylopectin content of native yam starch was 33.38% (217 g), 3.84 g/g, 1.0 v/g, 10%, 0.52 and 25.96, respectively, whereas gelation study of the native and modified starch indicated that native starch was viscous and modified starch firm. However, yield, swelling power, water holding capacity, paste clarity, blue value, and amylose content of modified yam starch reduced in a dose dependent manner with phosphoric acid. The reduction in the values of the various functional properties could be associated with the effect of phosphoric acid on the starch granular structure. The result of Fourier transform infrared spectroscopy and optical microscopy revealed that the yam starch was modified by phosphoric acid with changes in functional groups spectra such as –OH stretch (3177 cm^?1), H₂O absorbed (1644 cm^?1) (amorphous region), C-H stretch (2923 cm^?1), CH₂O (1253 cm^?1), and C-O-C (1078 cm^?1) when compared to native starch. The morphology of native and modified yam starch granules ranged from oval to eliptical. However, modified starch granules were rough in surface. In conclusion, the characterized physicochemical and functional properties and structure exhibited by native and modified yam starch indicated that, yam could be a cheap and valuable source of starch for industrial application.     

Physicochemical Properties and Starch Digestibility of Autoclaved-Cooled Water Yam (Dioscorea alata L.) Flour

Water yam (Dioscorea alata L.) is suitable for resistant starch high flour because of its high amylose content. The purple, yellow, and white water yams were treated by autoclaving and cooling with one, two, and three cycles to obtain resistant starch. Water yam tubers were cooked in an autoclave for 15 min, and then cooled prior to drying. Autoclaving–cooling of water yams decreased protein, fat, dietary fiber, water soluble polysaccharide, dioscorin, and diosgenin but increased amylose and sugar. The treatments significantly raised resistant starch and reduced in vitro starch digestibility that depended on water yam types, and affected starch granule morphology.     

铁棍怀山药中主要营养成分的研究

测定铁棍怀山药中的主要营养成分,并与普通淮山药的相应指标进行对照。结果表明,新鲜铁棍怀山药中固形物含量达28.67%,远高于普通淮山药13.86%的指标。铁棍怀山药中总氮量、总灰分、淀粉和粘性多糖含量分别为0.616%、2.03%、15.29%和1.59%,也高于普通淮山药的0.154%、1.36%、6.57%和1.47%的指标。证实铁棍怀山药比普通淮山药的营养与药用价值更高,值得进一步的研究和开发。     

Changes in the carbohydrate constituents of yam tuber (dioscorea rotundata,poir) during growth

The amounts of sugars, starch, hemicellulose and cellulose in yam tubers were estimated at different stages of maturity and in yam tuber (“EgbodO”) sections. Maltose, sucrose, glucose and fructose were the free sugars identified in the ethanolic extracts of the yam samples. Sucrose formed the bulk of the total sugars. The “bottom” portion of the “Egbodo” yam tuber was richer in total sugars (4.9%) than either the “middle” (1.8%) or the “head” (2.4%) regions. Starch accounted, respectively, for 60, 77 and 78% of total carbohydrates in the “bottom”, “middle” and “head” regions of the “egbodo” yam tuber. A peak value of 84% starch was obtained 6 months after planting the yam setts. Its decrease to 64% at 8 months has been partly attributed to reduced photosynthetic activity through yellowing and subsequent loss of leaves. The sum of cellulose and hemicellulose, regarded as non-available carbohydrates was less than 7% of the total carbohydrates. The linear fraction, amylose, formed about 17.8% of the starch prepared from whole yam tubers of varying maturities, and from yam tuber sections, the remaining being amylopectin. The observed amylose and amylopectin values did not vary significantly over the period of observation. These amylose and amylopectin fractions had iodine affinities of 17 and 0.1%, respectively.     

不同板栗品种(系)抗性淀粉综合评价

对72个板栗品种(系)栗仁中总淀粉、支链淀粉、直链淀粉、抗性淀粉、以及含水量等重要性状分析的测定,为不同板栗品种(系)的利用提供参考。结果表明,不同板栗品种(系)大小、色泽、形状不同;板栗品种(系)中总淀粉的质量分数在51.33%以上,质量分数最高为‘燕秋’,高达71.21%,质量分数最低的是‘波叶-8’,为51.33%;直链淀粉中含量最高的是‘燕秋’,质量分数为18.56%,最低的是‘大兰口’,质量分数为2.43%;支链淀粉含量最高的是‘金丰’,质量分数为58.35%,最低的是‘小官10’,质量分数为35.2%。板栗中含有较高的抗性淀粉。对不同板栗品种(系)中抗性淀粉进行综合评价,抗性淀粉含量最高的品种是‘燕秋’,质量分数为22.2%;最低的是‘徐玉明道’,质量分数为3.44%。通过对不同板栗品种(系)的淀粉进行相关性分析,表明板栗栗仁中直链淀粉与支链淀粉呈极显著负相关,支链淀粉与总淀粉呈极显著正相关,抗性淀粉与直链淀粉呈显著正相关。     

紫山药淀粉与其抗性淀粉理化性质的比较

以紫山药淀粉为研究原料,采用不同方法分别制备压热、酶解-压热及双酶纯化抗性淀粉,分析比较了紫山药淀粉与其抗性淀粉的理化性质。试验结果表明:紫山药淀粉颗粒呈圆形或椭圆形且表面光滑;抗性淀粉颗粒破碎且呈不规则型。4种淀粉的化学结构相似,与原淀粉相比,抗性淀粉没有生成新的基团。抗性淀粉样品的凝沉速度随直链淀粉含量的增加而加快,冻融稳定性则降低;碘吸收曲线向支链淀粉吸收波长方向偏移。流变学分析表明与原淀粉相比抗性淀粉表观黏度均增大,剪切结构恢复力与抗性淀粉含量成反比。     

人参山药挤压膨化工艺优化及其理化性质研究

采用双螺杆挤压膨化工艺制备人参、山药膨化制品,并研究其最佳工艺条件及其膨化前后理化性质的变化。以生晒参、山药饮片为实验材料,将生晒参粉与山药饮片粉按1:1比例混合,在单因素的基础上,以膨化制品的径向膨化率为考察指标,根据L₉(34)正交表进行正交试验,确定人参、山药复合粉挤压膨化的最佳工艺参数,并对膨化前后的营养品质、物理化特性、有效成分进行比较分析。结果显示:人参、山药复合挤压膨化的最佳工艺参数为:螺杆转速为250 r/min,Ⅲ区温度160 ℃,物料水分含量24%,在此条件下得到疏松多孔的膨化制品,产品径向膨化率达到最大值为2.43。人参、山药复合粉挤膨化后与膨化前营养化学成分相比,粗灰分含量差异不大(P>0.05),粗脂肪、TDF、IDF、粗蛋白质、可溶性蛋白质、总淀粉、支链淀粉含量均降低(P<0.05);可溶性膳食纤维、直链淀粉均有提高(P<0.05),分别提高了12.96%、18.03%。膨化后与膨化前物理特性比较,糊化度、WSI、WAI均有提高;人参、山药复合粉基本营养化学成分与物理特性相关性分析表明,膨化前后的糊化度变化率与淀粉含量变化率、支链淀粉含量变化率呈显著负相关(P<0.05),WAI值的变化率与IDF呈极显著正相关(P<0.01),WSI值与支链淀粉、脂肪、TDF、IDF含量变化率呈显著负相关(P<0.05)。膨化前后人参总皂苷由5.50%下降到5.15%,差异显著(P<0.05)。结论:通过挤压膨化技术的应用,使人参、山药复合粉的理化性质得到了改善,为进一步研究奠定理论基础。     

Gel Textural Characteristics of Corn,Cassava and Yam Starch Blends: A Mixture Surface Response Methodology Approach

Blends of native starches can be used to obtain special sensory properties avoiding the use of chemically modified starches. The mixture design approach was used to analyze the textural properties (hardness, adhesiveness, cohesiveness and gumminess) of gels obtained with different proportions of yam, corn and cassava starches (6% total solids) and related to microstructural characteristics. Maximum limits of 60% yam starch and 70% corn starch and minimum level of 30% cassava starch were fixed to minimize syneresis under storage. Hardness, adhesiveness and gumminess increased with the proportion of corn starch in the blends. The lowest values of hardness corresponded to the blends containing higher proportions of cassava starch, that has the lowest amylose content. Corn starch was the component that less contributed to cohesiveness. The characteristic high cohesiveness of cassava starch pastes (related to its higher amylopectin content) was reduced when it was mixed in adequate proportions with yam and/or corn starches. Gels containing only yam starch presented syneresis values close to 40% after 24° h storage at 4°C; the decrease of the maximum level of yam starch to 60% as well as the inclusion of cassava starch in the blends reduced weight losses. Disadvantages found in gels containing individual starches, such as exudate in yam and corn starch gels, and excessive cohesiveness in cassava starch gels, are minimized improving their possible applications, when blends are used.     

山药及零余子酸、酶处理淀粉的理化性质

利用酸和淀粉酶、糖化酶分别处理山药及零余子淀粉,利用扫描电镜、X射线衍射及流变仪等测定不同处理组淀粉的理化特性。结果表明：山药和零余子原淀粉颗粒较为完整,没有裂缝,呈卵圆形,表面光滑;酶、酸处理均会导致淀粉降解,酸处理淀粉表面破坏最为严重;零余子原淀粉、酸处理和酶处理的淀粉结晶度分别为32.02%、27.02%和31.13%,而山药原淀粉、酸处理和酶处理淀粉结晶度分别为34.32%、29.27%、33.55%。淀粉糊透光率、凝沉百分比表明零余子原淀粉最易老化,流变特性表明不同处理组的淀粉均具有弱凝胶特性。