Viscosity of sucrose solutions

Table H1.3.2 Viscosities of Sucrose Solutions Measured by a Capillary Viscometer"...

Viscosity will vary depending on the sample. Typical results for viscosity of sucrose solutions are shown in Table HI. 3.2. 

Figure 2.14 shows that the viscosity of sucrose solutions increases as a function of solute concentration. 

Cd(II) reduction at the mercury electrode from aqueous 1 M NaCl04 in the presence of sucrose was described [49] by CEE mechanism. An attempt was made to correlate the individual standard rate constants that became lower with increasing concentration of sucrose, with (1) the surface coverage by sucrose, and (2) the viscosity of the solution layer adjacent to the electrode surface. 

Other physical phenomena that may be associated, at least partially, with complex formation are the effect of a salt on the viscosity of aqueous solutions of a sugar and the effect of carbohydrates on the electrical conductivity of aqueous solutions of electrolytes. Measurements have been made of the increase in viscosity of aqueous sucrose solutions caused by the presence of potassium acetate, potassium chloride, potassium oxalate, and the potassium and calcium salt of 5-oxo-2-pyrrolidinecarboxylic acid.81 Potassium acetate has a greater effect than potassium chloride, and calcium ion is more effective than potassium ion. Conductivities of 0.01-0.05 N aqueous solutions of potassium chloride, sodium chloride, potassium sulfate, sodium sulfate, sodium carbonate, potassium bicarbonate, potassium hydroxide, and sodium hydroxide, ammonium hydroxide, and calcium sulfate, in both the presence and absence of sucrose, have been determined by Selix.88 At a sucrose concentration of 15° Brix (15.9 g. of sucrose/100 ml. of solution), an increase of 1° Brix in sucrose causes a 4% decrease in conductivity. Landt and Bodea88 studied dilute aqueous solutions of potassium chloride, sodium chloride, barium chloride, and tetra-... 

Solutions of synthetic polyglucoses have also been used for density-gradient centrifugation of viruses. 16 These substances are especially suited to this purpose, since they can be dissolved in water or buffer to yield solutions of high concentration and low intrinsic viscosity and a density similar to that of sucrose solutions. Because of their low rate of diffusion, polyglucoses form gradients that are more stable. A polyglucose nitrate possessed explosive properties, similar to those of starch nitrates and cellulose nitrates.200... 

The -maxima and minima on viscosity-composition curves are reminiscent of those on vapour pressure-composition curves of binary, mixtures. 5 The vapour pressures and viscosities are equal at some temperatures, say T and To, and T and To respectively. Then To/T—To7T =C(T —T), where C is a constant. A plot of TojT—To IT against T—T gives a straight line in many cases, both for vapour pressure and viscosity in other cases, the vapour pressure shows a minimum and the viscosity a maximum, and the vapour pressure a maximum and the viscosity a minimum. Prasad, 6 from the relation with vapour pressure deduced the equation rj =rjjrio= +ac, where c=conc. of non-electrolyte. The theoretical value of a is 0 00652 the observed values were glucose 0 44, fructose 0 44, sucrose 0 78, independent of temperature. According to Errera, the curves depend on the electric dipolarity of the liquids if both are nonpolar, the curve is concave to the composition axis whilst if both are polar, it is convex. Wolkowa found that the viscosity of a solution is approximately proportional to its heat of dilution. There seems to be no relation between the viscosity and surface tension of a mixture of acetic acid and water (cf. salt solutions, 13.VIII E). Mixtures of isomorphous substances obey an approximately linear relation. 

Launay and Pasquet (1982) studied the relationship between sweemess and solution viscosity using sucrose solutions thickened with guar gum prepared to two constant viscosity levels. The results showed that the sweetness intensity decreased in the presence of the gum, but this reduction was not dependent on the viscosity level, a result that seems to be in conflict with the results previously reported by Moskowitz and Arabie (1970). 

Stone, H. and Oliver, S. 1966. Effect of viscosity on the detection of relative sweetness intensity of sucrose solutions./. FoodSci. 31 129-134. 

Concentrations and types of sugars or oligosaccharides also affect the viscosity of pectin solutions. Chen and Joslyn (1967) and Kar and Arslan (1999a) found that sucrose, dextrose and maltose increased the viscosity of aqueous pectin solutions whereas dextrins reduced it. The viscosity-enhancing effect of the sugars was interpreted in terms of the decrease in dielectric constant of the solvent, dehydration action and hydrogen bonding formation. However, the effect of dextrins on the viscosity of pectin was apparently an artifact due to ionic impurities in the dextrin. 

VARIATION OF VISCOSITY WITH DEGREE OF INVERSION OF SUCROSE SOLUTION... 

Studied over pH range where there are no structural transitions in polymers (29). Dyes and polymers dissolved in 0.2M NaCl -f 0.1M buffer (citrate, phosphate, or carbonate). Viscosity of dye solutions changed by adding sucrose or glycerol to solution. Same patterns seen with polymers dissolved in water or in 3.0M NaCl + 0.1 M buffer... 

It is also of interest to examine the viscous behavior at higher concentrations. In an investigation of the aqueous solution viscosities of aqueous solutions of fructose, glucose and sucrose (4S) it was found that the measured viscosity had an exponential dependence on mole fraction of saccharide. A useful correlation was found of the form... 

There are similar temperature and concentration influences on the viscosity of aqueous solutions of many sugars and sugar alcohols. As an example, Fig. 19.2 shows viscosity curves for sucrose as a function of both temperature and concentration. 

Taimni JK (1929) The viscosity of supersaturated solutions. Part II. J Phys Chem 33 52-68 Palmer ML, Kushwaha K (1990) 6scosities of some organic acids in water and sucrose-water mixtures. Proc Natl Acad Sci India 60A 363-366... 

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