Cake emulsion

An ultrafiltration membrane has a pure water flux of 210 l/m".h at 3 bars. When an oil-water emulsion is concentrated at 4.5 bars the flux reduces to 35 due to a build-up of a cake ( emulsion ) layer. The specific resistance of this cake is r = 1.5 10 m . Calculate the thickness of the cake. The viscosity is similar to that of the water. 

Several other food emulsions can be quoted, such as coffee whiteners and cake emulsions. Coffee whiteners are O/W emulsions containing vegetable oils and fats covering the size range 1-5 pm and an oil volume fraction of 10-15%. The aqueous continuous phase contains proteins, e.g. sodium casinate, carbohydrates, e.g. maltodextrin, salts and hydrocolloids. The emulsifying system consists of blends of nonionic and anionic surfactants with adsorbed protein. 

AC Eliasson, K Larsson. In AC Eliasson, K Larsson, eds. Cereals in Breadmaking A Molecular Colloidal Approach. New York Marcel Dekker, 1993, pp 161-210. IS Shepherd, RW Yoell. Cake emulsions. In S Friberg, ed. Food Emulsions. New York Marcel Dekker, 1976, pp 217-275. 

Uses Emulsifier for foods, baked goods, dairy prods., edible oils/shortenings, confectionery volume improver, texturizer in cakes emulsion stabilizer in margarine crystallization retarder in starch jellies improves palatability and rehydration in dehydrated potatoes fat separation retarder, moisture retention aid, and extrusion aid in petfoods... 

Uses Food emulsifier in chewing gum, ice cream, coffee whiteners provides volume and texture in cakes emulsion stabilizer and film-former in caramels inhibits oil separation in peanut butter antispatter aid in margarine Regulatory FDA 21CFR 184.1505 Canada compliance kosher Properties Ivory wh. powd. or flakes, bland odor and taste sol. above its m.p. in veg., min. oils m.p. 144 F HLB 2.8 iodine no. < 5 flash pt. > 300 F 40-44% alpha mono... 

In a 500 ml. three-necked flask, fitted with a reflux condenser and mechanical stirrer, place 121 g. (126-5 ml.) of dimethylaniline, 45 g. of 40 per cent, formaldehyde solution and 0 -5 g. of sulphanilic acid. Heat the mixture under reflux with vigorous stirring for 8 hours. No visible change in the reaction mixture occurs. After 8 hours, remove a test portion of the pale yellow emulsion with a pipette or dropper and allow it to cool. The oil should solidify completely and upon boiling it should not smell appreciably of dimethylaniline if this is not the case, heat for a longer period. When the reaction is complete, steam distil (Fig. II, 41, i) the mixture until no more formaldehyde and dimethylaniline passes over only a few drops of dimethylaniline should distil. As soon as the distillate is free from dimethylaniline, pour the residue into excess of cold water when the base immediately solidifies. Decant the water and wash the crystalline solid thoroughly with water to remove the residual formaldehyde. Finally melt the solid under water and allow it to solidify. A hard yellowish-white crystalline cake of crude base, m,p. 80-90°, is obtained in almost quantitative yield. RecrystaUise from 250 ml. of alcohol the recovery of pure pp -tetramethyldiaminodiphenylmethane, m.p. 89-90°, is about 90 per cent. 

Tyj)e of dryer Applicable with dry-product recirculation True and colloidal solutions emulsions. Examples inorganic salt solutions, extracts, milk, blood, waste liquors, rubber latex, etc. Pumpable suspensions. Examples pigment slurries, soap and detergents, calcium carbonate, bentonite, clay sbp, lead concentrates, etc. does not dust. Recirculation of product may prevent sticking Examples filter-press cakes, sedimentation sludges, centrifuged sobds, starch, etc. 

Antifoams to reduce the risk of carryover employed emulsions of castor oil and similar substances. Caustic embrittlement was avoided by the use of quebracho tannins, chile niter (sodium nitrate), and salt cake (sodium sulfate), which was later discredited as an inhibitor. 

Abbreviations GC/FID, gas chromatography/flame ionization detection GC/MS, gas chromato-graphy/mass spectrometry GC/PID, gas chromatography/photoionization detection Includes groundwater, sludges, caustic and acid liquors, waste solvents, oily wastes, mousses, tars, fibrous wastes, polymeric emulsions, filter cakes, spent carbons, spent catalysts, soils, and sediments... 

Filtration through Hopkins and Williams kieselguhr filter-aid cake speedily removes even colloidal copper halides and breaks up any emulsion. 

Many other baked products, such as cakes, originate as both W/O emulsions and foams. Cake batter comprises a mostly W/O emulsion, with some O/W domains, that is also a foam containing small-sized air bubbles. Initially, the air bubbles are stabilized mostly by fat crystals. As the baking process gets underway the fat melts,... 

Many other foods are mixed dispersions, like ice cream which is an emulsion, foam, and suspension. Others abound. Sausages and frankfurters may be considered to be solidified O/W emulsions in which the oil droplets are covered by a protein membrane and dispersed in a gel [293]. Similarly, cakes can be considered to be air bubbles dispersed in a gel phase. 

With all polarization phenomena, the flux at a definite time is always less than the original value. When steady-state conditions have been attained a further decrease in flux will not be observed, i.e., the flux will become constant as a function of time. Polarization phenomena are reversible processes, but in practice, a continuous decline in flux can be observed. Such continuous decline is a result of membrane fouling, which may be defined as the irreversible deposition of retained particles, colloids, emulsions, suspensions, macro molecules, salts, etc. on or in the membrane. This includes adsorption, pore blocking, precipitation, and cake formation. 

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