Fluidity starch

Fluidity starches are made by hydrolyzing the starch in dilute acid below the gelatinization temperature of the starch. The range of fluidities is 20-90, with a 90 fluidity starch being very much thinner than a 20 fluidity. Fig. 2 gives an indication of the concentrations required to produce a given hot viscosity. 

These are used for bottle labeling. They are prepared by treating waxy starch or waxy fluidity starch with caustic under high shear. The starch swells in the caustic, and most of the caustic is neutralized with nitric acid. One formulation yields a final composition of 39% starch (40 fluidity waxy), 3% urea (an additive), 3% sodium nitrate (from the sodium hydroxide and nitric acid used), and 56% water (Ref. 10, p. 605). The viscosity as used is about 100,000 cP. The labels are cold water resistant. 

Starch octenylsuccinates offer excellent emulsifying properties, flavor oil retention and good oxidation resistance versus gum arabic. They can be made on a variety of starch bases, dextrins or fluidities which provide versatility and improved spray-drying costs. Starch octenylsuccinate are low in cost, domestically produced and are not subject to the market fluctuations that gum arabic encounters. 

Frequently used single-point viscosity tests in the starch plant are orifice pipettes,56 orifice funnels,57 the Hot Scott viscometer, and various methods to determine alkaline fluidity.58 For absolute measurements of the rheological properties, rotating viscometers with coaxial cylinders are used.59 The paper industry uses mainly the Brookfield viscometer and the Hercules viscometer for determining shear-dependent viscosity, pseudoplasticity, and thixotropy. Oscillatory and capillary viscometers are used for more detailed viscosity characterization, such as yield value, elastic properties, and viscoelasticity.60... 

Dextrins (pyrodextrins) are made by heating dry starch with or without acid. Since it is a dry process, recovery of water-soluble materials is simpler than with aqueous fluidity and oxidized starches. Depending on reaction conditions, greater or lesser amounts of three reactions will occur (a) hydrolysis (b) transglycosidation and (c) repolymerization. According to which predominates, the product is a white dextrin, a yellow dextrin or a British gum. Like other converted materials, these products offer a way to use higher solids to increase performance. 

Starches are used primarily in canned pet food, not in dry or semi-moist products. Canned pet foods with gravy require a stable, non-gelling thickener, so a highly-stabilized waxy maize starch is used. Fluidity com starches are used as gel formers for firm, cuttable loaf products.189... 

In the modified process, heating the starch mixture to approximately 95°C for 5 minutes Is sufficient. This mixture Is stored from a few hours to 2 weeks, depending on the mode of starch degradation selected. Longer storage of the degraded starch Is not detrimental, but prior to Its use It has to be mixed to uniform fluidity and transferred to the slasher, where It can be applied to the warp yam either at ambient or elevated temperatures (Table I). 

Poly(vinyl alcohol) may also be added if water resistance is required. Another formulation that does not require cooking to develop its adhesive characteristic is based on the cold, caustic conversion of an acid-modified starch (75 fluidity) (fi). Clay filler may be added to any case or carton sealing adhesive if the board being glued is too porous. 

Sawayanagi et al. [301] reported the fluidity and compressibility of combined powders, viz., lactose/chitin, lactose/chitosan, potato starch/chitin, potato starch/chitosan as well as the disintegration properties of tablets made from these powders in comparison with those of combined powders of lactose/MCC and potato starch/MCC. This was done in order to develop direct compression dilutents as a part of their studies on pharmaceutical applications of chitin and chitosan. 

These are the commonest type of starch used in confectionery and are used to make jellies, pastilles and wine gums. They are made by heating a dispersion of the starch with a small quantity of acid at a temperature below the gelatinisation point, where the effect is to reduce the molecular weight by hydrolysing a few of the bonds. This decreases the viscosityof the starch pastes as might be expected from theory. Starch suppliers have devised a system where these starches are classified by fluidity, where the fluidity is the reciprocal of the viscosity. Thus, in a series of fluidity numbers 20, 40, 60, 75 and 80, the 80 fluidity gives the lowest viscosity paste. 

Starch is a very widely used tablet excipient, but in its natural state, it does not possess the fluidity and binding characteristics needed as a tablet diluent. The major consolidation mechanism of starch is by deformation with a high elastic component.In addition, starch shows a high degree of lubricant sensitivity. 

The recovery of alcohol by distillation is very efficient with a typical total loss of alcohol between the fermentor and the anhydrous product of only 2%. It is also interesting to note that there is sufficient moisture contained in the grain to supply the chemical needs for conversion of starch to alcohol and to account for the 10% moisture content in the distillers grains. All additional water added to the system is simply to supply appropriate concentrations and streams of appropriate fluidity. 

The influence of the acid in this operation appears to be limited to increasing the fluidity of the aqueous solution of the starch, so helping the latter to combine with water. 

Introducing of starch and frequency rate of extmding influence the parameter of a melt s fluidity and explosive durability differently (tab. 1). 

Hydroxyethyl starch (HES), also known as hetas-tarch, is most often administered for intravascular volume expansion during the perioperative period and for resuscitation from trauma and shock. Because of its property of increasing blood fluidity, hydroxyethyl starch is sometimes infused to treat patients with disturbed microcirculation. 

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