Coagulation thermal

Table 4.1.28A. Potato protein concentrate (IFN 5-25-392). Derived from de-starched potato juice from which the proteinaceous fraction has been precipitated by thermal coagulation followed by dehydration. (From AAFCO, 2005.)...

It is easily observed that at high aerosol concentrations, individual particles coalesce to form larger chains or floes made up of many par-tides. The process of coagulation may be brought about solely by the random motion and subsequent collision of partides (often called thermal coagulation) or the collisions could be caused by such external forces as turbulence or electricity. In general, these external forces will act to increase the rate of coagulation. 

The simplest coagulation problem is thermal coagulation of monodisperse spherical particles. Since only the first several partide collisions are considered, the size of the resulting agglomerated partides... 

Thermal aggregation and thermal coagulation of milk proteins. 

Partial autoproteolysis has been successfully utilized for producing in industrial conditions food - grade, thermally coagulated, frozen protein gel from Antarctic krill. The protein recovery is about 80% of the protein content in the whole krill (Kofakowskiand Sikorski, 2000). 

It is concluded on the basis of equation [4.S] that the intensity of the particle loss due to the thermal coagulation is directly proportional to square of the particle concentration, while the coagulation efficiency increases with decreasing particle radius. This means that the coagulation of small particles at a high concentration is a very rapid process. Equation [4.S] is valid only for monodisperse aerosols, i.e. aerosols composed of particles of uniform size. However, the same qualitative conclusion can also be drawn in the case of polydisperse systems. 

Finally, it is to be noted that in the foregoing discussion of dry removal we considered the total ensemble of particles. If size ranges are taken into account separately, additional sinks have to be mentioned. Thus, thermal coagulation of particles with very small size, as well as the condensation (below a relative humidity of 100 %) of vapours with low saturation vapour pressure provide effective removal for Aitken particles. It is believed (Hidy, 1973) that these processes are dominant in the removal of aerosol particles in the size range below 0.1 /im radius. 

Because the mass of ammonium sulfate and sulfuric acid particles is mainly in the size range of active condensation nuclei, it is believed that this process provides a very effective removal mechanism for the tropospheric background aerosol. However, we have to emphasize that other processes are also operating in the cloud to remove small aerosol particles, of which the most important process is the coagulation of particles and cloud drops. As we have seen (Subsection 4.1.1), thermal coagulation is particularly effective in the range of very small particles inactive in condensation. To estimate this process, let us consider a cloud in which the number concentration of drops with radius rc is Nc. If the number concentration... 

There exists an extensive literature on the theory of coagulation (Fuchs, 1964 Zebel, 1966 Hidy and Brock, 1970 Twomey, 1977), and we can treat here only the most salient features. In the absence of external forces, the aerosol particles undergo collisions with each other due to their thermal (Brownian) motion. The mathematical description of thermal coagulation goes back to the classical work of Smoluchowski (1918) on hydrosols. Application to aerosols seems to have been made first by Whitlaw-Gray and Patterson (1932). Let dN, = f(r,) dr, and dN2=f(r2) dr2 describe the number densities of particles in the size intervals r, + dr, and r2+dr2,... 

Aerosol particles suspended in a fluid may come into contact because of their Brownian motion or as a result of their motion produced by hydrodynamic, electrical, gravitational, or other forces. Brownian coagulation is often referred to as thermal coagulation. 

The argon ion laser (488-514.5 nm) in the localized heating and thermal coagulation of the vascular choroid layer and adjacent retina, resulting in the anchoring of the retina in treatment of retinal detachment (Katoh and Peyman, 1988). 

In another work, [177] described the particle-size distribution of sulfate lignin based on thermodynamic model. This model suggests the formation of steady-state microstructure by aggregation of primary lignin particle into metastable clusters (aggregates) closely packed. The distribution of the statistical ensembles of particles is broadened and their average size increase with temperature due to the thermal coagulation process. 

Here, is the surface gradient operator and Ep is the coefficient of interfacial thermal elasticity, [cf Eq. (1)]. The drops moving with different thermocapillary velocities can collide and flocculate or coalesce this is the thermal coagulation. 

In the case of thermal coagulation, the drop velocity v is given by the expression (185) ... 

In the present study, we assessed the effect of heating and aqueous washing of mechanically separated seal meat (MSSM) and mechanically separated chicken meat (MSCM) on the content of sulfhydryl groups and disulfide bonds in their proteins. An attempt was made to correlate the content of sulfhydryl groups with changes in the solubility and thermal coagulation of mechanically separated meat proteins. 

Using thermal energy to destroy tumors and other malignant growths has been become a routine procedure for small lesions. Techniques such as high-intensity focused ultrasound [63—65] or laser thermal coagulation [66,67] can be used either non- or minimally invasively by directing... 

Deardorff DL, Diederich CJ, Nau WH (2001) Control of interstitial thermal coagulation comparative evaluation of microwave and ultrasound applicators. Med Phys 28 104-117... 

Potatoes from the natural sap left over after starch production, proteins can be isolated by thermal coagulation ... 

Green plants grown for animal fodder, such as alfalfa, which are processed into leaf protein concentrates through the thermal coagulation of ceU sap proteins. 

In several foods, proteins function as foamforming and foam-stabilizing components, for example in baked goods, sweets, desserts and beer. This varies from one protein to another. Serum albumin foams very well, while egg albumin does not. Protein mixtures such as egg white can be particularly well suited (cf. 11.4.2.2). In that case, the globulins facilitate foam formation. Ovomucin stabilizes the foam, egg albumin and conalbumin allow its fixation through thermal coagulation. 

Soya protein has a pronounced solubility minimum in the pH range of 3-6. The minimum is much less pronounced in the case of the unmodified plastein, whereas the glutamic acidenriched soya plastein has a satisfactory solubility over the whole pH range (Fig. 1.56) and is also resistant to thermal coagulation (Fig. 1.57). 

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