Emulsified retention

Feed—constituent interactions further affect retention (28,29). Dispersing agents and emulsifiers are partially retained because they attach to the dispersed phase. Small molecules may similarly adsorb onto larger particles. 

Fig. T A shows the GPC traces obtained at wavelength 2 k and 3U0 nm for a 312 nm Dow latex sample. Note the response at 3 0 nm is at twenty-five times the sensitivity of the response at 25 nm and hence considerably exaggerated in comparison. At 25 nm two peaks are clearly noted, a polymer peak and a secondary peak whose retention volume corresponds to that of styrene monomer. At 3 0 nm, since neither monomer nor polymer absorb, the observed peak is attributable to the presence of additives such as emulsifier.

Better retention into the fluorous phase was observed when using a polar fluorous solvent and hexane (>99.82%, insoluble catalyst emulsified in homogeneous reaction mixture) than when using a PFMC and acetone (97.5%), as expected for the ionic... 

AKDs are waxy, water-insoluble solids with melting points around 50 °C, and ASAs are viscous water-insoluble liquids at room temperature. It is necessary to prepare them as stabilised emulsions by dispersion in a cationic polymer (normally cationic starch). Small amounts of retention aid and surfactants may also be present. Particle size distributions are around 1 fim, and addition levels around 0.1% (of pure AKD or ASA) by weight of dry fibre. This is an order of magnitude lower than the amount of rosin used in rosin-alum sizing (1-2%). Emulsions of AKD are more hydrolytically stable than ASA, and the latter must be emulsified on-site and used within a few hours. 

As in the case of rosin sizing, the first step is to retain the emulsified size particle in the wet web. The mechanism of retention is probably by heterocoagulation of the cationic size particles to the negatively charged fibre surface. The charge characteristics of the stabilising polymer become important as demonstrated by the effect of pH on the retention of AKD emulsion particles stabilised with a tertiary cationic starch (Figure 7.17). 

Soy proteins are used extensively in meat and meat products by the military, the school lunch program and consumers to save money. Their ultimate acceptability is equally dependent upon the nutritional, chemical, sensory and shelf life changes which occur when they are added. Soy proteins in meat products such as ground beef inhibit rancidity, improve tenderness, increase moisture retention, decrease cooking shrink, fat dispersion during cooking and have no important effect on microbiological condition. Concomittantly, inordinate amounts of added soy protein may cause the meat product to be too soft, exhibit an undesirable flavor and may lead to a decreased PER and a deficiency in B-vitamins and trace minerals. In emulsified meat products, soy protein effectively binds water but does not emulsify fat as well as salt soluble muscle protein. Prudent incorporation of plant proteins can result in an improvement of the quality of the meat product with inconsequential adverse effects. 

MC is used as an adhesive in ceramics to provide water retention and lubricity in cosmetics to control rheological properties and in the stabilization of foams in foods as a binder, emulsifier, stabilizer, thickener, and suspending agent in paints, paper products, plywood as a rheology control for the adhesive in inks, and in textiles as a binder, and for coatings. 

Starch octenylsuccinates offer excellent emulsifying properties, flavor oil retention and good oxidation resistance versus gum arabic. They can be made on a variety of starch bases, dextrins or fluidities which provide versatility and improved spray-drying costs. Starch octenylsuccinate are low in cost, domestically produced and are not subject to the market fluctuations that gum arabic encounters. 

The hydrolyzed starches are inexpensive, bland in flavor, very soluble (up to 75 ), and exhibit low viscosity in solution. The major shortcomings of these products are a virtual lack of emulsifying capacity and marginal retention of volatiles. 

Gum arabic has been the standard of excellence as a flavor encapsulating material. It is an excellent emulsifier, bland in flavor, and provides very good retention of volatiles during the drying process (4). The major shortcomings of gum arabic have related to high cost and limited availability. 

Emulsions can be particularly troublesome. Over a period of time emulsified materials and/or other impurities usually will accumulate at the water/oil interface. In addition to adversely affecting the liquid level control, this will also decrease effective oil or water retention time in the separator, with a resultant decrease in water/oil separation efficiency. Addition of chemicals and/or heat often minimizes this difficulty. 

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