STUDIES ON COAGULATION PROCESS OF SOYMILKIN TOFU AND KORI-TOFU MANUFACTURE .8. CHANGES IN PARTICLE-SIZE DISTRIBUTION IN COAGULATION REACTION OF SOYMILK ADDED WITH CALCIUM-CHLORIDE

Changes in particle size distribution in coagulation reaction of soymi lk were measured by laser beam particle analyzer. When calcium chlorid e solution was continuously added to soymilk, the peak appeared at aro und 10 mum of particle size and then shifted to at about 100 mum. Prol onged stirring had no more effect to get particles with reduced sizes. The simultaneous measurement of stirring torque based on our previous report showed characteristic correspondences to the distribution chan ges of coagulated soymilk particles. The optimum coagulations conditio n deduced from the analyses of particle size distribution of coagulate d particles under various conditions were as follows concentration of soymilk ; around 5%, coagulation temperature ; 60 to 64-degrees-C, sti rring speed; around 140 rpm, and final concentration of calcium chlori de; around 10 mM. These results agreed very closely with those of the previous work by torque methods. The average size of coagulated partic les at optimum reaction conditions was around 200 mum by means of imag e analysis. Conclusively the final concentration of calcium chloride a nd the initial stirring speed were the most important controllable fac tors in order to get the desirable sizes of coagulated soymilk