Conditions f o r the formation of liquid two-phase water -proteinpolysaccharide systems containing the main classes o f proteins, as defined by Osborne, and various acid and neutral polysaccharides have been determined. Phase diagrams of some of these systems have been obtained. It is shown that, proceeding f r o m liquid two-phase water -proteinpolysaccharide systems, one can obtain different protein products without using spinnerets.

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The mechanical properties (tensile strength and deformation under uniaxial tension and shearing strength) as well as the stability against dissolution of the fibre obtained from the liquid two-phase system, water-caseinsodium alginate, can be much better than the properties of the fibres produced from binary systems, watercasein and water-sodium alginate, when concentrations of the macromolecular components and pH of the system are the same. These properties can be controlled by varying the composition of the system and by additional treatment in a 10% solution of CaCI, at 100 "C.In papers [I -61 it is shown that proteins can be processed into macroscopic monofilaments filled with ultra-thin (from 2 to 5 pm) continuous fibres, from liquid two-phase systems,

The process of concentration of skimmed milk proteins as a result of the phase separation of the waterskimmed milk proteins-polysaccharide systems has been studied. The two-phase systems were obtained by mixing and laying-up skimmed milk and polysaccharide solutions. Used QS polysaccharides were pectin, gum arabic and arabinogalactan. The establishment of the phase equilibrium in all the systems under study involves the concentration of the skimmed milk proteins and dilution of the polysaccharide solution. For the water-skimmed milk proteins-pectin system one can observe a transition of the lactose and calcium ions from the milk to the pectin solution. Depending on the concentration conditions. the concentration of the skimmed milk proteins in the protein phase increases by a factor of 5-12 as compared with that in milk. The dispersed phases of the water-skimmed milk proteins-gum arabic and water-skimmed milk proteinsarabinogalactan systems are represented by gel-like particles with skimmed milk concentrations of 30 and 45 wt %, respectively. A value of 30 wt % for the skimmed milk concentration seems to correspond to the critical concentration of the lyotropic gelation of the skimmed milk proteins. The largest involvement of the skimmed milk proteins in the protein phase (91 7;) of the water-skimmed milk proteins-polysaccharide system was observed to take place at 10 'C. a-Lactalbumin is the major protein component of the polysaccharide phase.This concentration process can be defined as a membraneless osmosis. The rate of the process was studied and the time of the establishment of equilibrium in the two-phase systems obtained by mixing and laying-up the solutions was estimated. The greater effectiveness of the membraneless osmosis was shown to be mainly ensured by a fairly large size of the interphase surface of the systems under study.

A . A V T O N~V and V. 9. T~L S T~G U Z O VA thermodynamic compatibility of skimmed milk proteins and polysaccharides (high-methylated apple pectin, gum arabic and arabinogalactan) with various molecular characteristics in aqueous media has been studied. At a certain composition and pH values all the systems studied can be two-phase. one of the phases representing a concentrated solution or a gel of skimmed milk proteins. The lowest compatibility is exhibited by the water-skimmed milk proteins-polysaccharide systems and the highest one by the water-skimmed milk proteins-arabinogalactan systems. Bodies of separation of the waterskimmed milk proteins-polysaccharide systems in the composition-pH coordinates have been obtained and discussed. Die Nahrung 30 (1 986) 6