淀粉凝胶储藏过程中消化特性和质构特性的变化

采用酶解法和全质构分析分别测定了红薯、绿豆和马铃薯淀粉凝胶在储藏过程中的消化特性和质构特性,并对消化特性与质构特性指标之间进行简单相关和逐步回归分析。结果表明:在25℃储藏10 d内,绿豆淀粉凝胶的老化性能强于红薯淀粉和马铃薯淀粉。淀粉凝胶的消化率降低,慢消化淀粉和抗性淀粉含量增加,快消化淀粉含量降低;淀粉凝胶的硬度随储藏时间的延长逐渐增加,回复值则逐渐减小。快消化淀粉含量、硬度和回复值可作为淀粉凝胶类食品的老化评价指标。     

淀粉种类对鲜湿面色泽及品质影响的研究

将小麦淀粉、马铃薯淀粉、红薯淀粉、豌豆淀粉及玉米淀粉添加到面粉中制作面条,从鲜湿面色泽、质构及感官三方面,研究淀粉种类对面条的影响规律。结果表明：不同淀粉均能改善鲜湿面的色泽,玉米淀粉效果最佳;质构影响方面,除红薯淀粉外,其他淀粉的添加使得面条的硬度下降,黏附性、回复性、粘聚性升高,坚实度和拉断力随添加量的增加呈先升后降的趋势;感官评价方面,玉米淀粉、小麦淀粉、马铃薯淀粉显著增大了面条的色泽得分,豌豆淀粉和红薯淀粉显著影响了韧性和粘性得分。     

凉粉草胶与不同淀粉混合体系糊化和质构性质的研究

凉粉草胶(MBG)与淀粉作用可以形成凝胶。为比较不同淀粉与MBG混合体系糊化和凝胶性质的差异,选取玉米等八种常见淀粉,利用Brabender糊化仪、质构仪、对MBG与不同淀粉混合体系的糊化和质构性质进行了研究。结果发现,MBG对谷类淀粉(大米、小麦、玉米)和豆类淀粉(绿豆、豌豆)的糊化性质的影响都比较显著,对薯类淀粉(木薯、马铃薯、甘薯)的不显著,但MBG与薯类淀粉混合体系的黏度远高于MBG与豆类和谷类淀粉的;MBG与大米淀粉形成的凝胶硬度最大,与马铃薯淀粉形成的凝胶硬度次之,与豌豆淀粉形成的凝胶硬度最小。淀粉与MBG之间相互作用的强弱可以从Brabender糊化曲线上的特征点值E-D来比较。     

Rheological and textural studies of fresh and freeze-thawed native sago starch–sugar gels. II. Comparisons with other starch sources and reheating effects

The viscoelastic and textural properties of freshly prepared and freeze-thawed sago starch–sugar gels were studied in comparison with other native starches from corn, wheat, tapioca, and potato. The gelatinisation and retrogradation properties of starches were studied using a DSC while the pasting properties of starch–sugar mixtures during the cooking period were studied using a starch pasting cell. The freeze-thaw stability of gels was evaluated by gravimetric measurements of the water of syneresis. The different starches gave properties which varied following to their botanical sources. High-amylose cereal starches (wheat and corn) produced harder gels, while low-amylose root starch (tapioca) produced softer gels. Sago and potato gels showed close similarities in their viscoelastic and textural characteristics. Although the freeze-thaw cycle greatly increased the viscoelasticity and hardness of these two gels, reheating at high temperature significantly reduced these negative effects and resulted in partial recovery of the gel structures. Sago starch produced gels with very low syneresis and high cohesiveness, implying its potential use as a gelling agent in the frozen food industries.     

Adsorption of Methyl Orange on Starches

Adsorption characteristics of methyl orange were investigated on kudzu, sweet potato, corn, rice, wheat, potato and snake gourd starches. No adsorption of methyl orange, an anionic dye, was observed on potato starch and snake gourd starch because of the presence of phosphate esters. Adsorption isotherms were found to fit both the Langmuir equation and Freundlich equation in all others. The degree of adsorption by kudzu, sweet potato, corn and wheat starches was related to the number of hydroxyl groups. We suggested methyl orange was confined to a monolayer on surface hydroxyl groups of the starches.     

不同淀粉对饼干口感润滑质地的影响

目的 探究不同植物源淀粉对饼干口感润滑质地的影响规律。方法 以不同植物源淀粉和面粉进行配比加入配料研制不同植物源淀粉饼干,结合流变学、感官评价、摩擦学参数考察其对饼干质地、口腔润滑及感官属性的影响。结果 不同淀粉饼干的润滑性结果为:马铃薯淀粉饼干>豌豆淀粉、红薯淀粉饼干>绿豆淀粉饼干,其结果与感官差异分析结果一致。结论 淀粉作为润滑质地调节剂,可以提高饼干产品口腔润滑性能,同时该研究也为口腔摩擦学用于主观感官分析提供参考。     

Morphological,thermal, rheological and noodle‐making properties of potato and corn starch

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     

不同品种绿豆的淀粉品质特性研究

为研究绿豆淀粉品质的品种变异性并从中筛选适宜加工的优良品种,选取我国16个绿豆品种,从中提取淀粉,并对淀粉的基本组成、糊化及凝胶特性进行了对比分析。结果表明,不同绿豆品种的总淀粉、直链淀粉及抗性淀粉含量存在不同程度的差异,其中总淀粉差异最小(变异系数2.32%)、抗性淀粉最大(变异系数22.77%),直链淀粉变幅为23.65%～34.08%。淀粉的糊化特性中,成糊温度的品种间差异最小、破损值差异最大,变幅分别为66.8～72.1℃及4.5～46.5 BU。凝胶特性中,硬度、黏附性和咀嚼度的差异尤为显著(变异系数>40%)。在所选取的绿豆样品中,中绿1号的淀粉易糊化,且淀粉糊的热稳定性强;郑绿8号及中绿10号的淀粉易老化、凝胶硬度大、弹性好。     

不同植物来源淀粉之间的理化性质的比较

本研究比较了绿豆淀粉、马铃薯淀粉、红薯淀粉、大米淀粉及玉米淀粉的理化性质,结果如下：绿豆淀粉具有最高的直链淀粉渗滤和胶凝值,并且这两个指标均与表观和总直链淀粉含量呈高度的相关关系。尽管绿豆淀粉具有最高的直链淀粉含量,但它并不显示出热糊稳定性。红薯淀粉在加热过程中具有高的膨润力和峰值黏度、高的崩溃值以及低的离水率,这表明红薯淀粉颗粒在加热时能够自由膨胀,糊的热稳定性差,淀粉的老化速率较低,而大米淀粉则与红薯淀粉相反。五种淀粉具有不同的胶稠度,马铃薯淀粉最高,而大米淀粉最低。离水率与直链淀粉含量不呈现明显的相关关系,因此其值的大小可能受其他因素的影响。     

葛根与几种植物的淀粉特性检测

在原有检测基础上对葛根、马铃薯、玉米、甘薯、糯米、籼米、白莲、高梁米、红腰豆、绿豆、燕麦及小米12 种植物淀粉进行更深入的特性实验,旨在快速检定葛根淀粉及其他淀粉。结果显示：葛根淀粉黏度、透光率、冻融稳定性、膨润力与溶解度等特性和其他植物淀粉有较大的差别,籍此可较快地鉴定葛根淀粉。     

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.     

葡萄籽原花青素对不同淀粉理化性质影响的研究

以绿豆淀粉、小麦淀粉和土豆淀粉为原料,研究了葡萄籽原花青素的添加(1%、2%、3%、4%),对不同淀粉理化性质(溶解度、膨胀度、耐酶解淀粉含量、硬度和冻融稳定性)的影响。结果表明:葡萄籽原花青素的添加使三种淀粉的膨胀度均有所升高,硬度显著降低,耐酶解淀粉的含量明显增多。在添加量3%时,土豆淀粉的冻融稳定性显著提高。此外,原花青素的添加使绿豆淀粉的溶解度提高,土豆淀粉的溶解度降低,但对小麦淀粉的溶解度影响不显著。     

Physicochemical Properties of Starches Obtained from Three Varieties of Chinese Sweet Potatoes

ABSTRACT: Starches isolated from 3 typical types of Chinese sweet potato varieties (XuShu18, SuShu2, and SuShu8) were characterized and compared with starches isolated from potato and mung bean. The 3 sweet potato starches differed in granule size; particle size distribution; protein, lipid, and phosphorus contents; pasting behaviors; swelling patterns; and syneresis. The retrogradation tendencies, measured both by setback ratio and by syneresis, differed for the 3 starches, although the amylose contents were quite similar (19.3 to 20.0%). Physicochemical properties of all 3 types of starches are evidently different from each other and from those of potato and mung bean starches. Keywords: sweet potato, starch, gelatinization, retrogradation, swelling, syneresis     

Starch Noodle Quality as Related to Potato Genotypes

Starch noodles were prepared using potato starch from 8 genotypes, mung bean starch, mung bean-potato starch blends, and sweet potato starch. The cooking quality of noodles from selected potato starches compared well with commercial starch noodles. Of the unblended potato starches, Mainechip exhibited cooking quality similar to commercial starch noodles with respect to cooking loss, cooked weight, and ?rmness. Appearance and texture of starch noodles from three genotypes (E55-35, Mainechip, and Shasta) were evaluated by a trained sensory panel. Noodles made from unblended potato starches had higher glossiness and transparency than those from other starches. Noodles from both un-blended and blended Mainechip starch had the highest press and elasticity.     

甘薯淀粉对山药凝胶肠理化特性的影响

为研究甘薯淀粉对山药凝胶肠理化特性的影响,对不同甘薯淀粉添加量下山药凝胶肠的质构特性、色度、热特性、水分状态、微观结构以及结晶特性进行了测试。结果表明：甘薯淀粉的添加显著增强了山药凝胶肠的硬度、胶着性、咀嚼性、内聚性和回复性,但黏性、弹性和白度下降;当甘薯淀粉添加量达到20%时,凝胶肠硬度达到7 060.65 g,胶着性为5 263.38 g,咀嚼性为4 623.80 g,内聚性为0.75,回复性为0.42,接近市售火腿肠的质地。甘薯淀粉的添加降低了山药凝胶肠的含水量和水分子的自由度,导致淀粉分子运动受限从而使相对结晶度和回生焓降低,凝胶肠质地更为致密。     

Starch noodles: History,classification, materials,processing, structure,nutrition, quality evaluating and improving

Starch noodles, produced from purified starch of various plant sources, are a major category of Asian noodles. This review summarizes the current knowledge on: (1) Definition, naming, history and categories of starch noodles. (2) The morphological, physico-chemical, thermal, rheological characteristics and molecular structure of materials including mung bean starch, pea starch, sweet potato starch, potato starch and corn starch. (3) Processing technology of starch noodles including dropping, extruding and cutting. (4) Structure of starch noodles: it is composed of hydrolysis-resistant crystalline zone, network-like framework and filler mass. (5) Nutrition of starch noodles: it could be evaluated by the digestibility of starch, hydrolysis properties of gelatinized and retrograded starches, hydrolysis property of starch noodles. (6) Quality evaluating of starch noodles: it includes sensory, cooking and texture property. Correlation between the physical properties of starch, processing variables and the sensory, cooking and texture property of starch noodles are summarized. (7) Quality improving for non-mung bean starch noodles: (a) using other materials such as red bean starch, pigeonpea starch, potato starch, sweet potato starch, corn starch, to substitute totally or partly mung bean starch; (b) adding chemically modified starch; (c) adding physically modified starch; (d) biologically treating starch; (e) using additives such as chitosan, polysaccharide gums.     

淀粉的慢消化性能与酶水解速率研究

研究了体外模拟条件下不同淀粉中营养片断,同时建立了酶水解动力学方程来探讨慢消化性能与酶水解速率的关系。结果表明,相比马铃薯与绿豆淀粉,玉米、蜡质玉米、小麦、糯米、大米等谷物淀粉属于理想的慢消化淀粉,它们的酶动力学水解速率小于1h-1,而马铃薯与绿豆淀粉的水解速率大于1h-1。淀粉的水解过程的反应动力学速率比Englyst法更能准确反映淀粉的消化性能。     

Determination of Sweet Potato Starch Mixed in Kudzu Starch by Moisture Sorption Method

Moisture sorption isotherms of kudzu starch, sweet potato starch, and their mixtures were measured at 20°C by a gravimetric method with a vacuum apparatus. Correlation was found between the mixture ratio of sweet potato starch to kudzu starch and moisture content of the mixed starches at a water activity of 0.750; the correlation coefficient was 0.9955. The moisture sorption method could be used to determine the amount of sweet potato starch mixed in commercial kudzu starch.     

Thermal and Rheological Properties of Mung Bean Starch Blends with Potato,Sweet Potato,Rice, and Sorghum Starches

Blending diverse starches is green and easy to diversify starch functionalities and to lower the cost of food production. Mung bean starch is commonly used to make starch noodles with good quality. Other starches may replace the mung bean starch to reduce the production cost. Four common starches (potato, sweet potato, rice, and sorghum) were added to mung bean starch with the mixing ratio up to 100 %. The gelling, thermal, pasting, steady shear, and dynamic rheological properties of these starch systems were studied and compared. One thermal endotherm was found in all starch blends, but individual components still tended to gelatinize separately based on calculations of melting enthalpy data. However, nonlinear changes in rheological and gelling properties were mostly found, and the data can be fitted by polynomial equations (order 2), indicating the existence of interactions among components during these tests. Granule size and amylose content of starch played important roles in the nonadditive behaviors.     

Moisture Sorption Characteristics of Kudzu Starch and Sweet Potato Starch

Moisture sorption characteristics of kudzu starch and sweet potato starch were investigated based on the results of moisture sorption isotherms at 11°C, 20°C and 30°C, thermal analysis, isosteric heat of sorption and entropy of sorption. The water of crystallization in sweet potato starch was strongly retained compared with that in kudzu starch. Differences in amount of moisture sorbed between kudzu starch and sweet potato starch seemed to be attributable to the stability of the microscopic structure. The interaction of moisture-sweet potato starch was stronger than that of moisture-kudzu starch. Amount of moisture sorbed and strength of moisture-starch binding of the starches, preheated to 110°C, decreased compared with those of the starches vacuum-dried at 20°C because of release of water from the amorphous part of the starch granule.