Extruding-expelling

More recently a new process known as extruding-expelling has been developed. Extruders are machines in which soybeans or other oilseeds are... 

Opapeju, F.O., Golian, A., Nyachoti, C.M. and Campbell, L.D. (2006) Amino acid digestibility in dry extruded-expelled soyabean meal fed to pigs and poultry. Journal of Animal Science 84,1130-1137. 

Woodworth, J.C., Tokach, M.D., Goodband, R.D., Nelsen, J.L., O Quinn, P.R., Knabe, D.A. and Said, N.W. (2001) Apparent ileal digestibility of amino acids and the digestible and metabolizable energy content of dry extruded-expelled soybean meal and its effect on growth performance of pigs. Journal of Animal Science 79, 1280-1287. 

Figure 7. Process flow diagram lor extruding-expelling soybeans.

Figure 8. Photograph inside a modern extruding-expelling plant processing soybeans. (This figure is available in full color at http //www.mrw.interscience.wiley.com/blofp.)...

Property Solvent Extraction Screw-Pressing Extruding-Expelling... 

Untoasted and flash-desolventized meal in which the protein is undenatured and highly soluble (>70 PDl and preferably >90 PDl) is the preferred starting material in manufacturing soy protein isolates. Under some conditions, extruded-expelled meal can be used, but the yield of soy isolate is reduced. The meal is ground in water adjusted to pH 8.0 with sodium hydroxide and centrifuged to remove insoluble fiber. The soluble fraction is acidified to pH 4.5, and the protein precipitates. The precipitated protein curd is separated from the soluble sugars by centrifuging. The protein curd may be washed, neutralized, and spray-dried. 

Lecithin recovered from solvent-extracted soybean oil had different phospholipid class compositions from those produced by mechanical pressing (198). The percentage of phosphatidylcholine was considerably higher in lecithin recovered from extruded-expelled oU than from solvent-extracted oil. The phosphatidylcholine- and phosphatidylinositol-enriched fractions produced by ethanol extraction of the crude lecithin also showed different functional properties (199). 

TABLE 1. Proximate Analysis of Dry Extruded-Expelled Soybean Meal. 

TABLE 4. Anaiysis of Extruding Expelling of Soybean, Cotton and Sunflower Seeds. 

Property Extruding-Expelling Solvent Extraction Screw-Pressing... 

Several researchers have studied the extruded-expelled meal for feeding trials for poultry, swine, and beef cattle. When compared with solvent-extracted meal, extruded-expelled meal is much better in nutrition and animals performance. 

Table 2.7 Quality comparison of oils and meals obtained by solvent extracted, extruded-expelled and screw pressed soybeans3...

Alternative techniques of vegetable oil refining have been developed. Simple refining methods were explored to process extruded-expelled (E-E) soybean oils with various fatty acid compositions (Wang and Johnson 2001b, 2001c). E-E... 

Figure 2.4 Phosphatidylcholine content of lecithin recovered from extruded-expelled (E-E) and solvent extracted (S-E) soybean oils. Abbreviations HO, high-oleic acid soybean oil LLL, low-linolenic acid soybean oil LOX, lipoxygenase-free soybean oil LS, low-saturated fatty acid soybean oil and CS, commodity soybean oil. Key , E-E B, S-E. 

The percentage of PC was considerably higher in lecithin recovered from extruded-expelled oil than from solvent extracted oil, as shown in Figure 2.4. 

Wang, T. and Johnson, L.A. (2001b) Natural refining of extruded-expelled soybean oils having various fatty acid compositions. J. Am. Oil Chem. Soc., 78, 161 166. 

Fig. 11.9. Photograph of the interior of an extruder-expeller plant operating on soybeans.

Quality Trait Hard Screw Pressing Extruding- expelling Gas-assisted Screw Pressing Solvent Extracting ... 

GSSP, gas-supported screw-pressed dehulled soybean cake EE60, extruded-expelled, dehulled soybean cake having 60 PDI EE35, extruded-expelled, dehulled soybean cake having 35 PDI. 

Lamsal, B.P. C. Reitmeier RA. Murphy LA. Johnson. Enzymatic hydrolysis of extruded-expelled soy protein and resulting functional properties./. Am. Oil Chem. Soc. 2006, 83, 732-737. 

Wang, T D.J. Myers L.A. Johnson. Value-added products from extruding-expelling soybean. Soybeans as a Functional Food K. Liu, C.Y. Wang, Eds. AOCS Press Champaign, IL, 2004. 

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