Soybean composition viscosity

Milk. Imitation milks fall into three broad categories filled products based on skim milk, buttermilk, whey, or combinations of these synthetic milks based on soybean products and toned milk based on the combination of soy or groundnut (peanut) protein with animal milk. Few caseinate-based products have been marketed (1,22,23). Milk is the one area where nutrition is of primary concern, especially in the diets of the young. Substitute milks are being made for human and animal markets. In the latter area, the emphasis is for products to serve as milk replacers for calves. The composition of milk and filled-milk products based on skim milk can be found in Table 10. Table 15 gives the composition of a whey /huttermilk-solids-hased calf-milk replacer, which contains carboxymethyl cellulose (CMC) for proper viscosity of the product. 

The phosphoric acid esters of diacyl glycerides, phospholipids, are important constituents of cellular membranes. Lecithins (phosphatidyl cholines) from egg white or soybeans are often added to foods as emulsifying agents or to modify flow characteristics and viscosity. Phospholipids have very low vapor pressures and decompose at elevated temperatures. The strategy for analysis involves preliminary isolation of the class, for example by TLC, followed by enzymatic hydrolysis, derivatization of the hydrolysis products, and then GC of the volatile derivatives. A number of phospholipases are known which are highly specific for particular positions on phospholipids. Phospholipase A2, usually isolated from snake venom, selectively hydrolyzes the 2-acyl ester linkage. The positions of attack for phospholipases A, C, and D are summarized on Figure 9.7 (24). Appropriate use of phospholipases followed by GC can thus be used to determine the composition of phospholipids. 

Wang and Briggs (in press) studied viscosity of soybean oils with modified fatty acid composition. The viscosity was expressed as... 

The composition of the fatty acids is a major factor aflecting the viscosity, and compositions of an oil or grade of TOFA can be expected to vary somewhat from lot to lot. Dimerization and oligomerization of the imsatmated fatty acids occur in the same temperature range at which the esterification is carried out. Fatty acids with conjugated double bonds dimerize more rapidly than those with nonconjugated bonds, and dimerization rates increase with the level of imsaturation. At the same ratio of phthalic to polyol to fatty acids, alkyds of the same acid number and solution concentration will increase in viscosity in the order soybean < linseed < tung. 

Table I-E-4 shows physical and chemical properties for No. 1 diesel fuel. No. 2 diesel fuel, and a typical biodiesel made from soy oil (Canakci, 2005). The fatty acid composition (%) for the soybean oil used was C16 0, 10.5 C17 0, 0.11 C18 0, 4.76 C18 l, 22.52 C18 2, 52.34 C18 3, 8.19, C20 0, 0.36 unknown components, 0.48 % saturation, 16.3. The composition of the biodiesel methyl esters prepared from the soybean oil is similar C16 0, 10.56 C17 0, 0.11, C18 0, 4.74 C18 l, 22.51 C18 2, 52.39 C18 3, 8.22 C20 0, 0.44 unknown components, 0.44 % saturation, 16.3. As seen from table I-E-4, the biodiesel has similar properties to fossil diesel. Biodiesel has a greater viscosity and tendency to gel than conventional diesel fuel, which restricts its use at low ambient temperature unless sufficient heating of the fuel and engine components is provided.

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