Utilisation of Amaranthus paniculatas (Rajgeera) Starch in Salad Dressing

Studies on utilisation of Amarantus paniculatas starch in salad dressings showed it to be more stable than corn starch. This is attributed to waxy nature of A. paniculatas starch.     

Studies on Applicability of Amaranthus paniculatas (Rajgeera) Starch for Custard Preparation

A. paniculatas or Rajgeera has been shown to contain 50–60% of waxy starch, having an extremely small granule size of 1–2 μm, and higher paste viscosity than corn starch. Studies on utilisation of Rajgeera starch for custard preparations showed it to be unsuitable for such purpose because of interactions among the various ingredients used in the formulation.     

Puffing Effects on Functional Properties of Amaranthus paniculatas (Rajgeera) Seed Flour

Among functional properties studied, water- anf fat-holding capacities were higher for puffed grain flour. Gelation was not affected, while foaming was adversely affected by puffing. A decrease in viscosity of flour pastes also resulted due to puffing.     

Studies on Cross-linked A. paniculatas (Rajgeera) Starch

Earlier studies from our laboratories on waxy A. paniculatas starch have shown it to be sensitive to mechanical shear and acidity. Cross-linking of this starch with phosphorus oxychloride at room temperature for ten min using 5 ml POCI₃ per 100 g starch improved the stability under canning conditions, low pH and also mechanical shear. Its paste clarity also improved distinctly. However, it had very poor freeze-thaw stability indicating it to be unsuitable for frozen foods. Evaluation of this starch in canned tomato soup showed it to be a useful thickener for foods processed under retort conditions.     

板栗淀粉糊特性的研究

探讨了板栗淀粉糊的透明度、凝沉性、冻融稳定性、流变性、抗剪切稳定性、触变性等性质 ,以期为板栗的深加工提供理论依据 ,促进板栗的发展     

板栗淀粉糊的特性研究

通过对板栗粉中占主要成分的淀粉的研究,为后期板栗粉冲剂开发提供试验理论依据,探讨了板栗淀粉糊的溶解度和膨润力、透明度、凝沉性、冻融稳定性以及凝胶强度等性质,并与小麦淀粉、玉米淀粉进行了比较。研究结果表明,从85℃开始,板粟淀粉的溶解度和膨润力都有很明显的上升;板栗淀粉的透明度低于小麦淀粉和玉米淀粉相似;凝沉现象随时间的增加比较明显;板栗淀粉的冻融稳定性和凝胶强度性质较其他两种淀粉出色。     

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.     

10种淀粉的理化特性研究

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。     

4种马铃薯淀粉糊流变特性的研究

对4种不同加工方式获得的马铃薯淀粉糊流变特性进行了探讨。静态流变特性测定结果表明,4种淀粉糊的流变模型为幂率模型,均为假塑性流体,每种淀粉糊以相同方式流动需要施加的力不同。在相同流动方式下,淀粉4粘度最大,其次为淀粉2,淀粉1和淀粉3的粘度近似相同。动态流变特性测定结果表明:随着温度的增加,淀粉1、2、4的弹性模量、粘性模量刚开始基本不发生变化,到60℃后,两模量急剧增加到最大值,然后降低到某恒定值。淀粉3的两模量随温度升高逐渐增加到最大值,然后逐渐降低到某恒定值。粘性模量达到最大后,淀粉2的粘性模量最大,其次为淀粉4、淀粉1,淀粉3的最低。弹性模量达到最大后,淀粉4的弹性模量最大,其次为淀粉2、淀粉1,淀粉3最低。     

肇实淀粉糊特性的研究

对肇实淀粉糊的透明度、冻融稳定性、凝沉性、流变性、抗剪切稳定性、触变性以及不同条件如温度、pH值、NaCl和蔗糖等对肇实淀粉糊的影响进行了研究,以期为肇实淀粉的加工、应用提供一定的理论基础。     

Effects of Storage on Dynamic Rheological Properties of Wheat Starch Pastes

The variation of the dynamic rigidities of wheat starch pastes during storage at various temperatures has been measured. The results suggest that a crystallization process is responsible for the observed increase in dynamic rigidity with time. The Avrami equation was used to interpret the results in an attempt to establish the mechanism of crystallization.     

Effects of Sodium Caseinate on the Rheological Properties of Starch Pastes

Effects of sodium caseinate on the rheological properties of starch-water pastes have been measured under steady shear conditions. In all cases a power law equation was found to describe the variation of viscosity with shear rate. The sodium caseinate increased the viscosity of the starch pastes and a starch-sodium caseinate synergistic effect occurred. Sodium caseinate caused the swollen starch particles in pastes to increase in volume. It is suggested that this is one of the factors responsible for the observed effects of sodium caseinate on rheological behavior.     

Lablab Bean Starch. I. Properties of its Granules and Pastes

The variety of lablab bean (Dolichos lablab) starch studied by the authors, presents smaller-sized, rounded granules, and others, larger ones, which are generally oval-shaped and measure up to 30 micra. These latter show 1, 2 or 3 polarization crosses under polarized light. The gelatinization temperature of the granules varies between 65–70–76 °C and iodine affinity shows a value of 6.05. Graphs were drawn for the swelling power, percentage of solubles, Brabender viscosity of the hot and cold pastes, and also for the observation of the effect of a-amylase on these pastes. It was observed that the starch pastes present the cross-linked type Brabender viscosity curves, which greatly resemble those of the chick pea, yellow pea and navy bean starches. Several theories relating to the composition and structure of the starch, and which might explain its behavior, were approached by the authors.     

Jack-Bean Starch. 1. Properties of the Granules and of the Pastes

Jack bean (Canavalia ensiformis) starch is composed of granules measuring up to 37 micra. Gelatinization temperatures of the granules range from 67.5 to 78 °C. Its pastes, in concentrations up to 6 % did not show swelling peak which appears only in high concentrations. They are very stable during stirring, both at low and high temperatures. They are also more resistant to α-amylase bacterial action than those of corn starch. The results, both for granules and pastes of this starch, show a great resemblance with the same data for guandu bean.     

Gamma-Irradiation Affects Some Physical Properties of Dry Bean (Phaseolus vulgaris) Starch

Gamma-irradiated great northern (GN) bean starch (2.5–20 kGy) showed apparent increased susceptibility to central fissures. Bean damage during scanning electron microscopy was observed using ≥400OX magnification on GN bean starch samples. Approximate molecular weights estimated by gel filtration chromatography Sepharose Cl-2B of control GN bean starch were: amylopectin >2×10⁶ and amylose 2×10⁵. Amylose-like fraction of irradiated bean starch (20 kGy) revealed two peaks ～6.9×10⁴ and 1.5×10⁵ daltons. Differential scanning calorimetry showed an increase in gelatinization enthalpy and a small increase in gelatinization peak temperature at 20 kGy suggesting a reorganization of the crystalline and amorphous phases of the starch granule.     

The Starch of Amaranthus — Physico-chemical Properties and Functional Characteristics

Starch from four varieties of amaranth grain were examined by scanning electron microscopy. Physico-chemical properties, including swelling power, solubility, water binding capacity, enzyme susceptibility, amylograph viscosity, and amylose, were determined. Functional characteristics, including bread and cake baking performance were studied. The granules of starch isolated from seeds of Amaranthus cruentus and Amaranthus hypochondriacus were found to be very small in size. They were angular and polygonal in shape. Compared to corn starch, the amaranth starches had a higher swelling power, a lower solubility, a greater water binding capacity, a lower susceptibility to α-amylase, a higher amylograph viscosity and much lower amylose content. The amaranth starches produced very poor quality breads and cakes. The breads and cakes were low in volume, lacked symmetry, and had inferior grain, texture and crumb color.     

Flow Behaviour of Mung Bean Starch Pastes

The rheological properties of mung bean starch pastes were characterised using a co-axial rotational viscometer. The flow curves of pastes were typical of a viscoplastic shear thinning behaviour, no yield value was evident and the pastes showed unusual resistance to high shear forces. The rheological properties of these pastes were thought to result from the combined influence of intact swollen granules and an extensive extragranular network of exuded amylose.     

Some Selected Physicochemical Properties of Buffalo Gourd (Cucurbita foetidissima HBK) Root Starch

The starch granules of buffalo gourd contained 30.5% apparent amylose, showed a high swelling power and gelatinised over 57-70.8°C with an enthalpy of 4.26cal·g⁻¹. The starch pastes had a stable peak viscosity with a resistance to fragmentation intermediate to those of cassava and potato starches during holding at 95°C. The starch gels displayed a higher storage modulus (G′) than that of corn starch and a viscous character similar to that of potato starch. These properties differ from the maize-like characteristics reported for this type of starch.     

Some Physicochemical Properties of Amylose-free Potato Starch

In this paper some physico-chemical characteristics of amylose-free potato starch are described and compared to those from amylose containing potato starches. The availability of these high-amylopection or amylose-free starches has opened up new possibilities to assess the relationship between structural characteristics and physico-chemical properties of potato starch. At the same time it should be possible to determine more precisely the role of the amylose in the starch on several properties and characteristics. In all different analyses it was clear that amylose-free starch displayed unique properties. Not only was the response to heating much faster; it also occurred at much higher temperatures as demonstrated by viscographs, differential scanning calorimetry and swelling experiments. Rheological analyses demonstrated that gels formed from amylose-free starch were less rigid, smoother and shorter. The breaking of amylose-free gels furthermore required much less strength than that of amylose-containing gels. This aspect was also evident when threads were made from both starches; amylose-free threads were much shorter before breaking than threads made from amylose-containing starch.