Drying techniques fractionation

Grain legumes have also been processed into refined starch (10,11) and protein isolates (12,13,14) by procedures derived from the traditional corn starch and soybean protein industries (15). However, comparative data on product yields, composition and losses have not been published. A commercial plant for the wet processing of field pea into refined starch, protein isolate and refined fiber has been established in Western Canada. Little is known about the characteristics of the protein isolate or refined fiber product. Water-washed starch prepared from the air-classified starch fractions of field pea (16,17) and fababean (6) have been investigated for certain physico-chemical and pasting properties. Reichert (18) isolated the cell wall material from soaked field pea cotyledons and determined its fiber composition and water absorption capacity. In addition, the effects of drying techniques on the characteristics of pea protein Isolates have been determined (14). 

Results obtained for mass loss by drying and for water content after KFT differ in many cases. With increasing a-lactose content the difference increases and is extreme for pure lactose. The drying techniques determine neither the total water nor the free water fraction alone. 

The method of removing the liquid from the slurry is critical. Spray drying determines the distribution of the oxide in the dry particles of oxide and catalyst, catalyst precursor or catalyst support to provide the product of this invention. The spray drying may be carried using conventional spray drying techniques and equipment. The chamber product from the chamber of the spray dryer is typically made up of porous spheroidal particles with diameters of about 30 to about 300 [jum. The cyclone product collected from the cyclone of the spray dryer is made up of porous spheroidal particles with somewhat smaller diameters. These spray dried particles may be sieved to obtain a fraction of particles with a narrower size distribution. The spray dried spheroidal particles are referred to herein as microspheres. As is well-known in the spray drying art, many of the porous microspheres produced have a void in the center with one or two openings to the outside. Such particles are referred to in the art as Amphora I-type and Amphora Il-type particles, respectively. 

In this chapter, we present the theory and results of measurements on humic acid fractions using fluorescence techniques. The fluorescence techniques are attractive for this application because of the natural fluorescence of humic materials, the hi sensitivity of fluorescence detection, and the ability to directly observe the morphology of the molecule in aqueous solutions without the need for drying or applying harsh chemical conditions. Several interesting types of information are obtained from fluorescence measurements ... 

This procedure was compared with sequential extractive techniques employing alkaline hydrolysis of dried plant tissue followed by extraction of the acidified mixture with ethyl acetate. Fractions were individually evaluated for phytotoxic properties. Selected fractions from those showing a positive response were analyzed by gas-liquid chromatography. Structural identification and characterization of the individual components in these selected fractions were accomplished by gas chromatography-mass spectrometry. 

Purification. The commercial LDPE was dissolved in hot toluene and precipitated in methanol. The resulting small chips were dried in a vacuum oven overnight at 80° C. HDPE was purified in the same manner, except that in this case much of the commercial material was insoluble in toluene, and so significant fractionation apparently occurs during t.he purification. The model compounds were purified by the flash chromatographic technique of Still et al. (10). 

Gershey et al. [58] have pointed out that persulfate and photo-oxidation procedures will determine only that portion of the volatile organics not lost during the removal of inorganic carbonate [30,79,92,181]. Loss of the volatile fraction may be reduced by use of a modified decarbonation procedure such as one based on diffusion [98]. Dry combustion techniques that use freeze-drying or evaporation will result in the complete loss of the volatile fraction [72,79, 92,93],... 

PCBs in biological samples are usually extracted by a Soxhlet column and with a nonpolar solvent such as hexane. The sample is first mixed with sodium sulfate to remove moisture. The extraction of PCBs from sediments was tested with sonication, with two sonications interspersed at a 24-h quiescent interval, with steam distillation, or with Soxhlet extraction (Dunnivant and Elzerman 1988). Comparison of the recoveries of various PCB mixtures from dry and wet sediments by the four techniques and the extraction efficiency of four solvents showed that the best overall recoveries were obtained by Soxhlet extraction and the two sonication procedures. In comparisons of solvent systems of acetone, acetonitrile, acetone-hexane (1+1), and water-acetone-isooctane (5+1.5+1), recoveries of lower chlorinated congeners (dichloro- to tetrachloro-) were usually higher with acetonitrile and recoveries of higher chlorinated congeners (tetrachloro- to heptachloro-) extracted with acetone were superior (Dunnivant and Elzerman 1988). The completeness of extraction from a sample matrix does not seem to discriminate against specific isomers however, discrimination in the cleanup and fractionation process may occur and must be tested (Duinker et al. 1988b). 

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