Studies on Starch Granules

In X-ray diffractometric studies on starch granules of many kinds of plant species, we found a variety of intermediate C-type patterns. In particular, specimens of sweet potato starch granules varied from nearly the A-type pattern to nearly the B-type pattern. In these studies, we also found that spheroids of short chain amylodextrin showed very sharp diffraction patterns and that we could form amylodextrin spheroids with various types of X-ray diffraction patterns by varying the conditions of recrystallization. Then we showed that the X-ray patterns and physical properties of many kinds of cereal and root starches varied to some extent depending on the environmental conditions prevailing during the growth period. We examined the formation and the growth of starch granules in corn endosperm and the inner structures of these granules from the beginning to the end of their maturation by electron microscopic observations. We proved also, the appositive growth of starch granules using radio-active carbon dioxide. Then we tried to form starch granules in vitro. But the spheroids obtained from solutions of starch components were entirely different from natural starch granules. From the findings in these experiments, an ultramacromolecular concept of the starch granule is proposed.     

Inorganic Impurities in Cationised Starch Granules

When cationised starch containing inorganic water-soluble salts is used in manufacture papermaking, salts that are not retained in the fibre web will accumulate in the white water of the paper machine. When the white water is recirculated, the inorganic salts are carried into the paper machine's process water. The presence of these salts in the process water constitutes a potential detrimental factor in paper-making. Point analysis of cross-sections of granules of dry and wet-cationised starch with a scanning electron microscope (SEM) and an energy-dispersive X-ray microanalyser (EDXA) revealed that the Cl content in dry-cationised granules was lowest in the central part of the granule (0.8%), higher at the layer under the surface (1.3%) and highest in the surface of the granule (2.5%). The starch sample contained on average (chemical analysis) 1.21% Cl, 0.43% Si and 0.58% Ca. The Cl content in cross sections of starch granules cationised in a water slurry proved to be the same in both the centre and the surface of the granule (0.4%). Chemical analysis of the starch sample revealed no Si and Ca, but 0.2% S.     

Studies on the Biosynthesis of Starch Granules. Part 7. Compound Granules in Potato Starch

The nature of compound starch granules in potato starch is examined. The relevance of this investigation to the possible formation of potato starch is discussed, and a mechanism for synthesis of compound granules proposed.     

玉米、木薯及马铃薯淀粉颗粒微晶结构及性质的研究

运用广角X射线衍射分析方法对玉米、木薯及马铃薯淀粉颗粒结晶结构及常温下水的溶胀作用对淀粉颗粒不同微晶结构的影响进行了系统研究,提出了在淀粉颗粒中存在着大量的介于微晶和非晶之间的亚微晶结构,并提供了在一条X射线衍射曲线图中确定微晶、亚微晶和非晶区域的方法。     

Thermal Conductivity of Starch Granules

Data were obtained at 25°C on thermal conductivities of slurries of starch in a carbon tetrachloride-ethyl benzene mixture having a density equal to that of the starch. The thermal conductivity of granular ordinary corn starch was estimated to be 0.125 B.t.u.-foot per hour-foot^2-0 F by calculation and by extrapolation from the slurry data. The thermal conductivities of granular corn starches decreased with increasing amylose content.     

葛根淀粉颗粒性质的研究

本文对葛根淀粉颗粒的性质进行了研究，包括淀粉颗粒的大小、形貌、X—射线衍射图谱、α—淀粉酶的酶水解作用方式等，并与玉米淀粉进行了比较。结果表明：葛根淀粉平均粒度为24．08μm，小于玉米淀粉的38．97μm；葛根淀粉和玉米淀粉颗粒的偏光十字接近颗粒中心，但葛根淀粉颗粒的偏光十字不明显；葛根淀粉的X—射线衍射图谱为C型，玉米淀粉为A型，而两者的结晶度分别为18％和37％；葛根淀粉和玉米淀粉对α—淀粉酶的作用极为敏感，但在酶解方式上，葛根淀粉是在淀粉粒表面形成许多微孔并经脐心进入淀粉粒内部，而玉米淀粉则是被层层水解，在淀粉粒表面形成很少的微孔。     

马铃薯淀粉双螺旋结构定量分析方法的研究

采用固体核磁共振技术(solid-state13C CP/MAS NMR)分别对天然马铃薯淀粉和无定型马铃薯淀粉进行测试并对得到的图谱进行分峰和拟合,以无定型马铃薯淀粉13C CP/MAS NMR图谱中C4在化学位移为84处的值为参考点,用Excel差减法从天然马铃薯淀粉图谱中减去无定型部分,再从得到的结晶淀粉图谱中分出由单螺旋和双螺旋结构所引起的峰,从而通过峰面积的比值计算出天然马铃薯淀粉中所含双螺旋结构的比例。     

Inner Structure of Potato Starch Granules

A combination treatment (dry-heat and glucoamylase) was applied on potato starch granules. Many inner granules in the granules after the treatments were observed by SEM. The inner granule located near edge of ellipsoid of granule was partially degraded X-ray diffraction pattern of starch granules did not change before and after the treatments in spite of over 50% loss by amylase digestion. GPC and iodine reaction of the sample showed the treatments brought about fairly large degradation of both amylopectin and amylose components, but GPC of debranched sample after the combination treatments showed amylose was thoroughly degraded while peaks pattern of amylopectin did not change. Small size granules were more susceptible than large size granules by the treatments.     

三氯氧磷变性木薯淀粉颗粒的显微分析研究

用扫描电镜（ＳＥＭ）和ｘ射线能谱仪（ＥＤＳ）研究了三氯氧磷变性木薯淀粉颗粒的形貌变化，对颗粒表面和内部的磷元素进行微区分析。结果表明颗粒形貌虽未变化，但不同微区的反应程度有差别，试剂先与颗粒表面发生反应，程度较高，后渗入内部，反应程度逐渐降低，液固相的淀粉化学变性为非均匀的反应。     

Studies on the Biosynthesis of Starch Granules. Part 9. The Starch Granules from Wrinkled-Seeded Peas

The nature of the complex granules of wrinkled-seeded pea starch has been examined, and related to changes in the starch during growth. An earlier hypothesis for the development of pea starch is shown to be untenable in the light of this information, and possible alternative mechanisms for the biogenesis of pea starch are discussed.     

Phosphorus and Amylose Branching in Rice Starch Granules

Phosphorus content of rice starch granules prepared by DoBS extraction of milled rice protein was lowest and was mainly 6-phosphoglucose for 2 waxy rices. For 6 nonwaxy rices it was highest and predominantly phospholipid P based on choline content. Defatting with water-saturated butanol reduced both choline and P content of nonwaxy rice starch. Once recrystallized amylose of 7 rices had 72–84% β-amylolysis limit, DP 532–793 glucose units per reducing end, CL 101–157 glucose units per nonreducing end and 3.4–7.5 branches/molecule.     

Characterization of Starch Granules in Maize Using Microspectrophotometry

Starch granule-associated proteins and protein aggregates not associated with starch granules were visualized by staining with acid fuchsin. Based on fluorescence intensity, it was observed that non-granule-associated proteins could be removed from starch granule preparations by treatment with a modification of the Osborne-Mendel fractionation method without affecting the apparent level of granule-associated proteins. Moreover, fluorescence microscopy with direct spectrophotometric measurement of the proteins confirmed the presence of major subpopulations of granules differing in size and acid fuchsin-induced fluorescence. Treatment of stained granules with 1.0% SDS dramatically reduced fluorescence intensity, indicating the removal of granule-associated proteins.     

Scanning Electron Microscopy of Enzyme-digested Starch Granules

The study deals with comparison of the susceptibility to fungal glucoamylase and salivary α-amylase of starch granules from navane, panivaragu, black pepper and black gram. The crude glucoamylase was purified by fractionation and column chromatography to give two pure fractions of which one was used. The rate of amylolysis was followed by estimating the amount of glucose and maltose released. The type and extent of damage of the starch granules were observed by scanning electron microscopy which revealed characteristic degradation patterns in navane and panivaragu, whereas black gram granules were resistant to the attack. Very small-sized black pepper starch granules did not exhibit any obvious signs of amylolytic attack.     

非晶颗粒态淀粉的制备研究

介绍了一种简单的制备非晶颗粒态淀粉的方法。将原淀粉在一定温度下用乙醇和碱的混合液处理,用HCl中和,醇洗,最后在50℃左右的烘箱中干燥6h,得到非晶颗粒态淀粉(NCSG)。在偏光显微镜下观察未看到偏光十字,表明淀粉的结晶结构发生了变化。比较通过X射线衍射图谱而测定的结晶度,结果表明淀粉的结晶度降低即大部分的淀粉多晶结构变成非晶结构。光学图片显示NCSG保持完整的颗粒形态,扫描电镜结果表明NCSG失去了甲坦或光滑的表面,而变得粗糙或伴有不同程度的凹陷。不同的反应条件,颗粒的形貌不尽相同。较低浓度的醇,较高浓度的碱或较高反应温度,淀粉颗粒表面粗糙些。反之,颗粒表面光滑。     

In vivo Digestion of Banana Starch Granules

Approximately 50% of either potato or banana granules ingested by rats fed diets containing the starch granules as the main carbohydrate disappeared in the rat bodies with making corrections for starches in feces and in posthumous contents of the gastro-intestinal tracts. By scanning electron microscopy starch granules isolated from the digestive tracts of rats showed typical patterns of the enzymatic attack, probably those of α-amylase attack, on their surface layers and inner portions. SEM observations of the cross-section of a grain of feces of rats fed with diets containing starch granules of banana and potato revealed that damage of starch granules can be observed without the tedious procedure of separating starch granules from feces.     

Microscop of Rice Starch Granules During Cooking

Starch from five cultivars of rice was pasted in the Brabender viscograph and then held at 95°C for 60min. Granules were examined by light and scanning electron microscopy. In concentrated (12%) pastes, low-amylose rice starch showed total granule disintegration after 60min of cooking at 95°C, but highamylose granules showed only marginal disorganization. Waxy starch granules were disintegrated even at 70°C. In dilute (1%) pastes, on the other hand, granules swelled without appreciable disruption, apparently more in low than in high amylose starch. Clearly low amylose starch granules were weak and fragile and so swelled as well disintegrated easily, while high amylose rice starch was relatively strong and rigid and so resisted swelling as well as disintegration. This relative regidity/fragility of starch granules seemed to be the key to differences in rice quality.     

Interaction of Iron Compounds and Starch Granules

The adsorption of several iron compounds by unmodified and modified tapioca, corn and waxy maize starch was studied using transmission electron microscopy and atomic absorption spectrophotometry. Starch was incubated in an iron-containing solution. After centrifugation the amount of iron remaining in solution was compared to the original concentration to determine the quantity bound by the starch. Only iron in the form of colloidal ferric chloride showed significant binding. Long, cigar shaped structures, probably β-ferric oxyhydroxide crystals, were seen embedded in the surface of the granule. It is postulated that the oxygen and hydroxide groups surrounding the iron are responsible for binding to the carbohydrate. The study of the interaction of starch and metal compounds may lead to greater insight into methods of fortifying food products.     

Swelling and Reactivity of Maize Starch Granules

It is concluded that granule swelling is required for any chemical derivatization of common yellow dent maize starch with fatty acyl chlorides in organic solvents, even for reaction at granule surfaces. It was also concluded that progressively less of hot pyridine-swollen granules is available for reaction with fatty acyl chlorides as the carbon chain length increases from C₆ to C₁₄, with those two lengths being the approximate outside limits for partial exclusion.     

Optical Interference Studies on Single Starch Granules

Studies on the optical interference by potato, sorghum, wheat, pigeon pea and cowpea starch granules indicated that the potato granule was ordered mostly on the centre of the granule and that the molecular arrangement of the birefringent portion was perpendicular to the radial. This was more so with the legume starches where the entire granule was ordered. Cereal starches had birefringent material on the periphery and non-birefringent material in the centre and in this case, the birefringent material was radially arranged.