Rheological properties modification

The Cassia angustifolia GaM possesses the potential to become a new source of commercial gum due to its high content in the endosperm (about 50%) and its valuable rheological properties. It was suggested, in a similar way as for other GaMs, for usage as an additive in pharmaceutical formulations [188, 246]. Also the Ipomoea seed gum in its natural form, and after modification by grafting, has the potential to be used as a commercial gum [178]. 

Favorable rheological properties are an essential requirement for the commercialization of polyolefins like polyethylene. The ease of processability of the polymer melt, obtained through modifications in the microstructural features, is as important as the end use mechanical properties of these polymers. Presence of long-chain as well as short-chain branching, LCB and SCB, respectively, more or less dictates the rheological behavior of most commercial... 

The stress relaxation properties of SA-modified wood in media of different pH have also been studied (Nakano etal., 1990a,b, 1991 Nakano, 1993a,b). It was found that an increase in pH led to an increase in stress relaxation properties due to side chain ionization, with maximum swelling of the wood occurring between pH 5-8. In addition, cross-linking within the wood was achieved by treatment with bivalent or trivalent metal ions. The rheological properties of maleic acid esterified wood also show that thermoplasticity is imparted to the wood by such modification (Norimoto etal, 1992). 

Meissner, J. Modification of the Weissenberg rheogoniometer for measurement of transient rheological properties of molten polyethylene under shear. Comparison with tensile data. J. Appl. Polymer Sci. 16, 2877-2899 (1972). 

Huang, X.L., Catignani, G.L., and Swaisgood, H.E. 1999. Modification of the rheological properties of whey protein isolates by limited proteolysis. Nahrung 43, 79-85. 

Gupta, S., deMan, J.M. 1985. Modification of rheological properties of butter. Milchwis-senschaft. 40, 321-325. 

Vasic, I., deMan, J.M. 1967. Measurement of some rheological properties of plastic fats with an extrusion modification of the shear press. J. Am. Oil Chem. Soc. 44, 225-228. 

Milk fat is valued for its pleasant flavor but its melting and rheological properties often need to be modified to make it more suitable for many food applications. The uses of milk fat can be increased by the application of various processing interventions such as fractionation, selective blending and texturization, and chemical or enzymic processes to produce speciality milk fat ingredients (Kaylegian, 1999). Most of these modification procedures... 

Wright, A.J., Marangoni, A.G., Hartel, R.W. 2002. Lipids Rheological properties of and their modification. In Encyclopedia of Dairy Sciences, Vol. 3 (H. Roginski, J.W. Fuquay, P.F. Fox, eds.), pp 1577-1583, Academic Press, London Academic Press, London. 

On the other hand, in the treatments involving no cell wall modifications, the modification of mechanical properties is due only to the nonzero value of Vp and Ep. For the simulation, rheological properties of polymethyl methacrylate (Ep = 4.5 GPa, tan 8p = l/(0Tp = 0.065 at a)/2 tt = 250 Hz [13]) were used. Line (a) in Fig. 6 shows the effect of increasing values. The closed circle on line (a) corresponds to the average experimental Vp value (= 0.5 for a WPG = 126 % and = 1.2). This theoretical prediction shows good agreement with the experimental shift shown on the same graph. 

Brush marks. Lines of unevenness that remain in the dried paint film after brush application. Brush marks and ropiness are associated with poor flow and sticky application. These defects are more often encoimtered in highly pigmented products and in certain latex paint formulations. Tbo rapid recovery of consistency in a thixotropic system will also cause these defects. The remedy may be the addition of a flow promoter, reduction in consistency, or modification of the rheological properties. 

Producers normally rely on only a few source oils indigenous to their geographic area or that can be imported economically. Soybean is the primary oil used in the United States while very little palm is consumed and none is produced. Canada s major oil is canola (low-erucic-acid rapeseed). Malaysia, Indonesia, and Central America are the largest producers and users of palm oil. Eastern Europe, like Canada, relies on low-erucic-acid rapeseed (LEAR), sunflower, and soybean oils. It is apparent from Table 3 that it is virtually impossible to formulate products with controlled melting and crystalline properties using only one of these oils. Even in areas where conditions and economics justify a variety of types, modification methods other than blending are essential to adequately control rheologic properties. 

Modification of the Properties of Fats and Oiis Transesterification reactions (interesterification and acidolysis) of triacylglycerols have been an important tool in fats and oils processing for the modification of their physical and rheological properties by changing the composition and distribution of their fatty acids. 

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