甘肃主要杂豆淀粉理化特性分析

以甘肃产三角豌豆、白豌豆、小白芸豆、麻豌豆为材料,采用湿磨法提取淀粉,以玉米、马铃薯及绿豆淀粉为对照,对杂豆淀粉的理化特性进行分析。结果表明：参试杂豆淀粉颗粒多呈卵圆形,偏光十字较明显,多呈“X”形和斜十字形,部分淀粉颗粒呈现明显多脐点现象,平均粒径为21～29μm,其中三角豌豆淀粉的粒径最大而麻豌豆淀粉颗粒最小;淀粉颗粒的结晶类型与绿豆淀粉相同,为C型。其直链淀粉含量远高于玉米淀粉和马铃薯淀粉,且麻豌豆＞小白芸豆＞白豌豆＞三角豌豆淀粉。杂豆淀粉属限制型膨胀淀粉,起糊温度为72.6～78.8℃,且具有较好的热糊和冷糊稳定性,淀粉糊的透明度较高,但凝沉速度均极快,冻融稳定性也都较差。4种杂豆淀粉的理化特性与绿豆淀粉相近,可耐受高温处理,但不宜用于冷冻类食品的生产。     

Effects of Granule Sizes on Physicochemical Properties of Cross‐linked and Acetylated Wheat Starches

Large and small wheat starch granules were used for cross‐linking and acetylation to determine effects of granule sizes on physicochemical properties of the modified starches. The native and cross‐linked starches from the small granules showed higher phosphorus contents than did those from the large granules. However, the level of phosphate substituents in the modified starches was not significantly different between the large and small granules under the same conditions. In contrast, the large granules had a higher reactivity with acetic anhydride than did the small granules. The phosphate group cross‐linked starch (CS), acetylated starch (AS) and acetylated cross‐linked starch (ACS) from the large granules had lower gelatinization temperatures and higher enthalpies than those from the small granules. The paste viscosities of the CSs from the large granules decreased rapidly, whereas those of the AS or ACS increased significantly as compared with those from the small granules. The pastes of cross‐linked starches from the small granules were more stable than those from the large granules, whereas the pastes of AS and ACS from the large and small granules had similar resistance to freeze‐thaw treatment. Scanning electron microscopy (SEM) also showed that the small granules were less damaged after modification than the large ones. Thus, the different granule sizes resulted in different physicochemical properties of starch after modification.     

The effect of acid and glucoamylase hydrolysis on partial physicochemical properties and characteristics of Dioscorea alata Linn. starch

Dioscorea alata Linn. (D. AL) rich in starch was widely used as food and medicine. This work aimed to compare the effect of acid and glucoamylase on the starch of different reaction time. The physicochemical properties of the native and hydrolyzed starches, such as swelling power (SP), starch solubility (SOL), and paste clarity were also determined in this study. The native and modified starches by acid and glucoamylase were compared and characterized by scanning electron microscope (SEM) and secondary derivative FT‐IR spectroscopy. The morphological characteristics of native D. AL starch granules revealed by SEM varied from round to oval or elliptic with smooth surface. SEM showed that glucoamylase primarily attacked the exterior of starch granules and permeate into the interior by the cracks formed on the surface. Owing to acid hydrolysis, the starch granules were depressed and transformed to bread‐like in shape and then broke into irregular lumps with particles adhered. From secondary derivative FT‐IR spectrum, the intensities of the two peaks from acid and enzyme hydrolysis starches at 1137 and 1066/cm were stronger than native starch. Some new peaks appeared due to hydrolysis. The digested starches exhibited a lower SOL and SP than native starch in water as the temperature increasing. The light transmittance of the digested starches was significantly higher than that of native starch paste and decreased with increase in storage period.     

Physicochemical characterization of mung bean starch

Starch from mung bean (Vigna radiata) was isolated and some of the important characteristics determined. The yield of starch was 31.1% on a whole-seed basis. The shape of the starch granule was oval to round to bean shaped, with granules 7–26 μm in diameter. Scanning electron micrographs revealed the presence of smooth surfaces. The gelatinization temperature range was 58–67–82°C and the enthalpy of gelatinization was 18.5 J/g. The total amylose content was 45.3%, of which 12.1% was complexed by native lipids. The X-ray diffraction pattern was of the ‘C’ type and the X-ray intensities were much stronger than in other legume starches. The starch exhibited a high swelling factor ( 43.6 at 95°C) in water. The viscoamylographic examination of the starch paste (6% w/v) showed the absence of a peak viscosity, a low 95°C viscosity [200 Brabender units (BU)], an increase in consistency ( 140 BU) during the holding cycle at 95°C and a set-back of 220 BU. Native granules were readily hydrolyzed by porcine pancreatic α-amylase (76.4% in 72 h). Retrogradation of mung bean starch (as measured by changes in syneresis, gel strength, enthalpy and X-ray diffraction intensities) appeared to be more severe than in other legume starches.     

Effect of acid‐ethanol treatment followed by ball milling on structural and physicochemical characteristics of cassava starch

Structural and physicochemical characteristics of cassava starch treated with 0.36% HCl in anhydrous ethanol during 1 and 12 h at 30, 40, and 50°C followed by ball milling for 1 h were analyzed. Average yield of acid‐ethanol starches reached 98% independent of the treatment conditions. Solubility of acid‐ethanol starches increased with reaction temperature and time, but it did not change after ball milling. Granule average size reduced with chemical treatment from 25.2 to 20.0 µm after 12 h at 50°C. Ball milling decreased the granule average diameter of the native starch and those chemically treated at 30°C/1 h or 40°C/1 h, but it did not alter the starches treated for 12 h, independent of temperature. From scanning electron microscopy (SEM), starch granules presented round shape and after modification at 50°C/12 h, before and after ball milling, showed a rough and exfoliated surface. Some granules were deformed, suggesting partial gelatinization that was more intense after milling. Starch crystallinity increased as temperature and time of chemical treatment were increased, while amylose content, intrinsic, and pasting viscosities decreased. Gelatinization temperatures increased for all chemical starches. The findings can be related to the preferential destruction of amorphous areas in the granules, which are composed of amylose and amylopectin. After ball milling, the starch crystallinity decreased, amylose content, intrinsic, and pasting viscosities kept unchanged and gelatinization temperatures and enthalpy reduced. Ball milling on native and chemical starches caused the increase of amorphous areas with consequent weakening and decreasing of crystalline areas by breaking of hydrogen bonds within the granules.     

Physicochemical properties and in vitro digestibility of flours and starches from taro cultivated in different regions of Thailand

This research aimed to study physicochemical properties and in vitro digestibility of flours and starches from taro cultivated in different regions of Thailand, that is, Kanchanaburi (KB), Chiang Mai (CM), Phetchaburi (PB) and Saraburi (SB). Taro starches were extracted from taro flours using either water or alkaline extraction. The taro flours had significantly (P ≤ 0.05) larger particle size, higher pasting and gelatinisation temperatures, and resistant starch content but lower total starch content, whiteness (L* value), paste viscosities and clarity than their corresponding extracted starches. All the taro starches exhibited polygonal and irregular granules and gave A-type X-ray diffraction pattern. The alkaline-extracted taro starches had significantly (P ≤ 0.05) higher extraction yield, total starch content, L* value, pasting and gelatinisation temperatures, and paste clarity but lower granular size, amylose content, resistant starch content, paste viscosities and relative crystallinity than their water-extracted counterparts.     

The Starch of the Fababean (Vicia faba). Comparison with Wheat and Corn Starch

Fababean starch (Vicia faba) was prepared by air-classifying a fababean flour, but then required repeated water extractions to reduce the protein content to a level comparable to that found in laboratory-prepared corn- and wheat starches. Scanning electron microscopy of the fababean starch showed oval or irregularly shaped granules which were larger in average particle size than those of corn starch. Fababean starch had a higher amylose content, gelatinization temperature range and water-binding capacity, but a lower swelling power and solubility at 90 °C compared to wheat- and corn starch. Amylograph viscosities were in-between values recorded for the other 2 starches at each reference point. The observed differences in physico-chemical characteristics between the cereal starches and the legume starch were not large.     

羟丁基化水平对玉米淀粉理化性质的影响

以玉米淀粉为原料,1,2-环氧丁烷为醚化剂,氢氧化钠为催化剂,乙醇为分散剂,制备出不同取代度的羟丁基淀粉。采用傅里叶变换红外仪、X射线衍衍射仪和扫描电镜等对不同取代度的羟丁基淀粉的微观结构进行表征。红外分析表明羟丁基淀粉在1371cm-1出现羟丁基的吸收峰,证明已经接上了羟丁基基团。X射线衍射分析羟丁基淀粉仍属于A型衍射图,证实了该反应主要发生在无定形区。通过扫描电子显微镜分析变性前后的表面形貌变化,表明该反应发生在淀粉颗粒表面。布拉班德粘度仪测试结果表明,淀粉糊化温度降低,回复值降低,糊峰值黏度升高,且随着取代度的提高,变化越明显,当取代度达到一定程度时,羟丁基淀粉冷水可溶。随着羟丁基取代度的增大,淀粉糊的透明度及冻融稳定性都有显著的提高。     

4种杂豆淀粉结构特征和理化特性比较

以4种我国广泛种植的杂豆为原料，采用湿磨法提取豇豆淀粉、扁豆淀粉、豌豆淀粉、红芸豆淀粉，并对4种杂豆淀粉的结构特征和理化特性进行比较。结果表明：杂豆淀粉的红外光谱均呈现典型的淀粉类多糖结构特征，颗粒完整光滑，主要呈现肾型和椭圆形。样品的平均流体力学半径大小顺序为豇豆淀粉>豌豆淀粉>扁豆淀粉>红芸豆淀粉，扁豆淀粉为CC-型晶体，其余为C_A-型晶体，样品间的相对结晶度差异较大(27.6%～38.5%)。4种杂豆淀粉的糊化特性差异显著，糊化温度均较高(75.3～82.8℃)，不易糊化。豇豆淀粉直链淀粉含量最低(26.3%)，其热糊稳定性优于其他杂豆淀粉，具有不易老化的特性。红芸豆淀粉的直链淀粉含量最高(31.5%)，回生值最高(3 182.3 mPa·s)，最易发生老化行为。综上，4种杂豆淀粉的颗粒形貌相似，均为C-型晶体，分子结构和糊化特性差异较大，凝沉特性相近。     

不同直链淀粉含量对羟丙基氧化玉米淀粉性质的影响

本文采用蜡质玉米、普通玉米和高直链玉米淀粉为原料,改变有效氯添加量,制备羟丙基氧化淀粉,通过XRD、DSC、Brabender粘度仪等测定手段,研究不同直链淀粉含量对羟丙基氧化淀粉理化性质的影响。实验表明,直链淀粉含量对羟丙基化和氧化程度影响显著,其中直链淀粉含量高有利于羟丙基化,而不利于氧化;X-射线衍射分析发现,改性淀粉没有改变晶型,随氧化程度增加,淀粉分子结晶度下降,直链淀粉含量越高,下降趋势越缓;DSC测试和Brabender粘度分析表明,直链淀粉含量直接影响到羟丙基氧化淀粉糊化特性,糊化温度:高直链普通蜡质,糊粘度:蜡质普通高直链,糊化焓:蜡质普通高直链;通过观察淀粉的偏光特性和颗粒表面形态,发现直链淀粉含量越高,羟丙基氧化淀粉的偏光十字越弱,颗粒越不易破碎。     

Characteristics and application of octenyl succinic anhydride modified waxy corn starch in sausage

Native and acid‐hydrolyzed wx corn starches were modified by octenyl succinic anhydride (OSA) in aqueous slurry systems. The characteristics of the modified wx corn starches and their effects on chicken meat sausages were evaluated by means of FT‐IR, rapid visco analyser, SEM, and texture profile analysis. FT‐IR spectroscopy indicated that the ester carbonyl groups in the OSA modified native and acid‐hydrolyzed starches were characterized at 1725 cm⁻¹. The process of OSA modification could achieve starch derivatives, which had higher viscosities, better paste clarity and freeze–thaw stability than the native counterparts. Texture results showed that the hardness, springiness, cohesiveness, and chewiness of the sausage increased as OSA‐H0 was added (p < 0.05). SEM revealed that the sausages with native wx corn starch had larger and uneven pores, while it was comparatively compact for the sausages with OSA starches. The OSA modified wx corn starch offered a great potential to be used in meat products to enhance textural quality.     

Hydroxypropylation of pigeon pea (Cajanus cajan) starch: Preparation, functional characterizations and enzymatic digestibility

Hydroxypropyl starch derivatives were prepared from pigeon pea starch (NPPS) which is an unconventional starch source. Functional parameters and characterization of both native and modified starches were carried out. The starch granules appeared oval or elliptical in shape with sizes ranging from 7 to 40 μm in width and 10 − 30 μm in length. Hydroxypropylation did not alter the shape of the starch granules in a pronounced way. Generally, the x-ray diffractograms of native pigeon pea starch showed the “A” pattern. However, slight reductions in the diffraction intensity of starches after modification were observed. At all temperatures studied (30-90 °C), swelling and solubility of hydroxypropylated starches were higher than the NPPS. Progressive increases in swelling capacity and solubility were observed as the molar substitution (MS) increased among the hydroxypropylated starches. Hydroxypropylation reduced starch paste turbidity on storage. Also, studies showed that syneresis reduced after hydroxypropylation. In addition, syneresis reduced as the MS of the hydroxypropyl starches increased. The results indicate that pasting temperature and peak temperature reduced after modification but peak viscosity increased in hydroxypropylated starch derivatives compared with the native starch. Setback reduced in hydroxypropylated starches compared with the native starch. Enthalpy of gelatinization and percentage retrogradation reduced after hydroxypropylation and progressive reductions were observed as the MS increased among the starch derivatives. Hydroxypropylation increased enzymatic digestibility.     

Feinkornstärken und hydrophile Polymere als Komponenten für neue biologisch abbaubare Zweiphasenwerkstoffe für spezielle Anwendungen Teil 1: Separations- und Aufbereitungstechniken für Feinkornstärken von Quinoa und Amaranth

Small Granule Starches and Hydrophilic Polymers as Components for Novel Biodegradable Two-Phase Compounds for Special Applications Part 1: Separation and Refinement Techniques for Small Granule Starches from Amaranth and Quinoa A small technical scale process for the separation and special refinement of small granule starches from amaranth and quinoa seed was developed using basic starch technology and machinery equipment as well as a neutral extraction process with xylanases and other enzymes. By using aqueous alkaline media for starch extraction, instead of water, the native starch structure was irreversibly changed, as indicated by Brabender and RVA peak viscosities as well as damaged starch measurements. The functional properties of these smallest native starch granules (0.5–3.0 μm) were investigated for novel applications in starch-compound products. Extrusion compounding processes for the formation of two-phase compounds from small granule starches and synthetic thermoplastics with polar structure units request native starch structures with high thermal stability.     

Succinylated Dioscorea cayenensis starch: Effect of reaction parameters and characterisation

Starch was extracted from Dioscorea cayenensis (yield, 87.2%) and it was subjected to succinylation under different reaction conditions. The succinyl amount and the degree of substitution (DS) in starch increased as the concentration of succinic anhydride, time and temperature increased. Optimal DS (0.217) and % succinyl content of 11.82 could be achieved at starch: catalyst (pyridine) ratio of 1:1, succinic anhydride concentration of 4% w/w at 120°C and 4 h of reaction. Succinylation did not alter starch crystallinity remarkably. Native starch granules appeared oval, round and spherical with sizes in the range 15–31 µm (length) and 10–20 µm (width). Both swelling capacity and solubility improved after succinylation. Succinylation increased paste clarity and it was dependent of the DS and storage time for the paste. Pasting temperature was reduced after modification and as the DS increased among the starch derivatives. The peak viscosity of the native starch was lower than the viscosities of all the modified starches. Succinylation reduced setback values but increased breakdown. Percentage syneresis was reduced after succinylation and progressive increases in percentage syneresis were observed as the number of cycles of freezing–thawing increased. In vitro enzyme digestibility reduced after succinylation and progressively as the DS of the modified starch increased.     

Characterization of Pea Starches in the Presence of Alkali and Borax

Refined field pea (Pisum sativum L.) starches were prepared from air‐classified pea starch by washing or from whole pea by wet milling, and analyzed for their physicochemical and pasting characteristics in the presence of alkali and borax. Commercial corn and high amylose corn starches were included in the study for comparative purposes. The two pea starches exhibited similar physicochemical characteristics. Amylose content markedly influenced pasting and other characteristics of the corn starches. Pea starch and high amylose corn starch exhibited little viscosity development during pasting in deionized water. The presence of alkali or borax significantly altered the peak viscosities and cold paste stabilities of all four starches in a concentration dependent manner. Alkali and borax increased peak and cold paste viscosity and reduced syneresis in all cases.     

Structure,functionality, and digestibility of acetylated hulless barley starch

Hulless barley starch was extracted and further acetylated using acetic anhydride at different level (3.75, 7.5, 11.25 g/100 g) in this study. The structure changes and functional properties of acetylated hulless barley starches comparing to the native starch were evaluated and analyzed. The shape of granules remained unaltered with cracks formed after modification. Small- (1 μm) and large-sized (20 μm) were observed in four kinds of starches while granule particle sizes distribution changed dramatically. Four hulless barley starches presented A-type x-ray diffraction pattern, with relative crystallinity of 25.6, 27.1, 26.2, and 24.8% for native and acetylated starches. The infrared ratio of 1045/1024 and 1025/995 cm^?1, indicated the difference in long-range order of crystallinities and short-range order of double helices. Results observed in swelling power, gelatinization parameters, pasting viscosities, and in vitro digestibility indicated acetylated hulless barley starch’s potential as a functional food additive and a healthy ingredient.     

干热处理对藜麦淀粉结构和理化性质的影响

以高筋小麦粉为原料添加酵母制作面团,在温度28℃、湿度80%条件下发酵1～6 h,提取小麦淀粉。研究发酵时间对小麦直链淀粉含量、损伤淀粉含量、粒径、颗粒表面结构、糊化及消化特性的影响。结果表明：面团发酵1 h后直链淀粉含量和损伤淀粉含量均显著低于原淀粉(P<0.05)。快速黏度分析结果表明,发酵1 h的小麦淀粉峰值黏度、热浆黏度和冷浆黏度最低。发酵处理后淀粉的粒径均小于原淀粉,其中发酵5 h的平均粒径最小。扫描电镜结果表明,发酵6 h的小麦淀粉颗粒表面出现破裂现象。体外消化实验表明,发酵5 h和6 h小麦淀粉的消化速率最高,发酵后抗性淀粉含量低于原淀粉,而慢消化淀粉含量高于原淀粉(P<0.05)。     

Studies on Isolation and Characterization of Starch from Rajgeera Grains (Amaranthus paniculatus Lin.)

Isolation and some of the important physicochemical properties of starch from rajgeera grains have been investigated. The yield of starch was about 61.2%, on whole grain basis. The results on physicochemical properties revealed that it exhibited moderate swelling and higher solubility (55.5%) in water, as compared to other millet starches. An extensive solubility in dimethylsulphoxid (72.5%) of the starch indicated easy penetration of solvent in a granular matrix, may be due to labile and heterogenous bonding forces within the granules. Brabender viscoamylographic data on pasting characteristics revealed that it yielded low viscosity (448 B. U.) at concentration of 10% (w/v) and showed very little tendency to retrograde during cooling of the starch paste. The amylopectin content was 88.5% indicating the starch of rajgeera is probably waxy in nature. Amylolytic digestibility of native and gelatinized starch of rajgeera by human salivary α-amylase and glucoamylase was investigated.     

Physicochemical properties of cassava,potato and jicama starches oxidised with organic acids

The oxidising effects of organic (acetic, citric and lactic) acids on the physicochemical properties of starches from cassava, potato and jicama were investigated. Cassava starch oxidised with lactic and citric acids had the highest carbonyl contents (5.43 and 5.84 g kg^?1 respectively), while oxidised potato starch had the highest carboxyl contents. Oxidised jicama starch showed the lowest carbonyl and carboxyl contents. Oxidation increased the maximum viscosity of cassava starch (from 426.61 to 670.11 relative viscosity units (RVU)) and jicama starch (from 160.17 to 561.50 RVU) but decreased that of potato starch (from 669.44 to 206.92 RVU). When carbonyl and carboxyl groups were incorporated into jicama starch granules, the resistance of these granules to stirring at constant temperature (holding) increased, as did their final and retrogradation viscosities. However, the behaviour of oxidised cassava and potato starches, as indicated by a Rapid Visco Analyser, was different. The highest values of endotherm enlargement were found for native and oxidised jicama starch, while the lowest values were found for native and oxidised cassava starch. Native and oxidised potato starch had the highest enthalpy values (14.30–18.30 J g^?1), while jicama starch had the lowest (9.50–11.9 J g^?1). The high intrinsic viscosity of native potato starch was attributed to B‐type starch with a longer‐than‐average amylopectin chain length and a lower degree of crystallinity. Oxidised granules showed little erosion in the form of grooves; on the contrary, oxidation left the grains with a very smooth surface. Copyright © 2007 Society of Chemical Industry     

Granular Properties of Different Starch Phosphate Monoesters

Different starch types (corn, rice, and potato starch, corn amylose and corn amylopectin) were phosphorylated by reaction with a mixture of mono and disodium phosphate at different molar ratios (mol phosphate/mol anhydrous glucose) under heat and vacuum. The starch granules of the modified and the native starches were microscopically examined for their sizes and morphology. The correlation between the variation in granular size of the modified starches with the extent of phosphorylation and some other physicochemical properties was studied. The granular size was generally increased while the iodine absorption capacity was decreased by phosphorylation. There were strong correlations between the variation in the starch granular size in dependence on phosphorylation and the corresponding changes in some physicochemical parameter of starch, e.g. solubility, swelling and paste clarity. This relationship was most evident in the case of phosphorylated corn amylopectin. Starch granular size can be taken as a quick indicator of the physicochemical properties of the native and modified starches.