Degumming

The SOFT degumming process removes non-hydratable PLs by using a chelating agent (i.e. EDTA), which forms complexes with Ca + and Mg + salts of PA and improves interfacial exchange properties (Choukri et al 2001). This process produces degummed oil with low residual phosphorous ( 5ppm) and iron ( 0.05 ppm) contents. 

The main limitations of conventional membrane processing are short membrane life, low temperature and pressure ranges for polymeric manbranes, sensitivity of membranes to chlorine, and instability of membranes at high and low pH ranges. Membrane oil degumming 

Response surface methodology was used to optimize enzymatic rapeseed oil degumming process parameters (Yang et al., 2006). Lecitase Ultra was used to degum rapeseed oil. The optimal conditions were determined as follows enzyme dosage 39.6mg/kg, temperature 

3 °C and pH 4.9. The process produced rapeseed oil with 3.1 ppm phosphorous content. The process was then scaled up to 400 tonnes oil/day production. Degumming process efficiency was significantly affected by pH at the large scale. When the pH was maintained between 4.6 and 5.1, phosphorous content in the degummed rapeseed oil could be reduced to less than lOppm. 

In general, enzymatic degumming minimizes oil retained in the gum, resulting in improved oil yields. The enzymatic hydrolysis reaction typically requires 5-6 hours and utilizes less water than water and acid degumming processes. Reductions in enzyme production costs and enhanced enzyme activity and stability could make enzymatic degumming process very attractive for oil refining industry in the near fumre. 

This processing step is of special importance for rapeseed and soybean oils. Water (2-3%) is added to crude oil, thereby enriching the phospholipids in the oil/water interface. The emulsion thus formed is heated up to 80 °C and then separated or clarified by centrifugation. The crude lecithin (cf. 3.4.1.1) is isolated from 

Finely dispersed protein and carbohydrates are coagulated in oil by addition of phosphoric acid (0.1% of oil weight). A filtering aid is then added and the oil is clarified by filtration. This also removes the residual phospholipids from the previous processing step. 

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Degrees API Degrees of freedom Degudent Deguelin [522-17-8] Degumming D.EH. 

Silk degumming Silk Screening Silk-screen inks Silkworm Silky II Polydek Sillemanite Silkmanite Sillimanite [12141-45-6]... 

Before the fibers can be spun into yams, a certain amount of preparation is necessary for cleaning and removal of undesirable accessory materials such as fat, wax, gum, or pulp. The weighting of sUk is a process to counter the weight loss resulting from degumming the fibers using heavy metal salts of tin or bismuth. This process affects the durabUity and long term preservation. 

Cmde soy lecithin is obtained as a by-product during the degumming process of soy oil. The phosphoms-containing compounds are removed to improve the stabiHty of the oil. 

Fig. 2. Flow sheet of lecithin producing unit. Crude soybean oil is heated in the preheater, 1, to 80°C, mixed with 2% water in the proportion control unit, 2, and intensively agitated in 3. The mixture goes to a dweUing container, 4, and is then centrifuged after a residence time of 2—5 min. The degummed oil flows without further drying to the storage tanks. The lecithin sludge is dried in the thin-film evaporator, 6, at 100°C and 6 kPa (60 mbar) for 1—2 min and is discharged after cooling to 50—60°C in the cooler, 8. 9 and 10 are the condenser and vacuum pump, respectively.

The total commercial lecithin potential if all vegetable oils were degummed worldwide would be 552,000 t (Table 7). Although soybean, sunflower, and rape lecithins are available in the market, the principal commercial interest is only in soybean lecithin. The aimual worldwide production is 130,000 t (Table 8). 

Rice-Bran Wax. Rice-bran wax [8016-60-2] is extracted from cmde rice-bran oil. It can be degummed, the fatty acid content reduced by solvent extraction, and bleached. The wax is primarily composed of esters of lignoceric acid (43 wt %), behenic acid (16 wt %), and 22 02 alcohols (28 wt %). Rice-bran wax may be used in some food apphcations under the regulations described in 21 CFR 172.890. 

Fats and Oils. The oxidation of fats and oils in food products can be prevented by the addition of citric acid to chelate the trace metals that catalyze the oxidation. Citric acid is also used in the bleaching clays and the degumming process during oil refining to remove chlorophyll and phosphohpids (59—63). 

Other tests include assessing the colorfastness to solvents, felting treatments, stoving, vulcani2iag, merceri2ing, degumming, etc. 

Degen, m. sword, deglutieren, v.t. swallow, degommieren, v.t. degum. degorgieren, v.t. = ausschlammen. 

Entsau(e)rung, /. deacidiflcation deoxidation, entschadigen, v.t. indemnify, compensate for. entschalen, v.t. shell, peel (Silk), scour, degum. 

Kotgeruch, m. fecal odor, kotig, a. fecal, stercoraceous dirty, filthy, kotonisieren, v.t. cottonize degum (silk). Kotorinde,/. coto bark. 

Degudent, gold-based dental alloy, 8 307t Degumming, of oils, 10 807 DEHA, 2 549t... 

A practical enzymatic procedure using alcalase as biocatalyst has been developed for the synthesis of hydrophilic peptides.Alcalase is an industrial alkaline protease from Bacillus licheniformis produced by Novozymes that has been used as a detergent and for silk degumming. The major enzyme component of alcalase is the serine protease subtilisin Carlsberg, which is one of the fully characterized bacterial proteases. Alcalase has better stability and activity in polar organic solvents, such as alcohols, acetonitrile, dimethylformamide, etc., than other proteases. In addition, alcalase has wide specificity and both l- and o-amino acids that are accepted as nucleophiles at the p-1 subsite. Therefore, alcalase is a suitable biocatalyst to catalyse peptide bond formation in organic solvents under kinetic control without any racemization of the amino acids (Scheme 5.1). 

The process involves reacting the degummed oil with an excess of methyl alcohol in the presence of an alkaline catalyst such as sodium or potassium methoxide, reaction products between sodium or potassium hydroxide and methyl alcohol. The reaction is carried out at approximately 150°F under pressure of 20 psi and continues until trans-esterification is complete. Glycerol, free fatty acids and unreacted methyl alcohol are separated from the methyl ester product. The methyl ester is purified by removal of residual methyl alcohol and any other low-boiling-point compounds before its use as biodiesel fuel. From 7.3 lb of soybean oil, 1 gallon of biodiesel fuel can be produced. See FIGURE 12-5. 

Figure 6 Steps involved in oil refining (a) degumming, (b) eaustie treatment, (e) bleaehing, and (d) dewaxing...

Silk in iis raw siaie is coated with scricin. It is necessary to remove this gum in order to develop ihe silk luster and dyeability. Synthetic detergent systems, such as higher alcohol sulfaies, and soda ash and boric acid have replaced soap to a large extent for degumming. 

From a technical standpoint, phospholipids (e.g., from soybean) are composed mainly of lecithin, cephalin, or phosphatidylinositol. These complex mixtures (2-3% in soybean oil) are hydrated during the degumming step, removed, and dried. These products are sold as commercial lecithin used in margarines, confections, and shortenings where a fat-soluble emulsifier is required. 

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