Hen's egg white is a key ingredient in many food products because of its ability to aggregate when heated. However, the output of processed goods using egg white has been limited upto date. If egg white lost the ability of thermal coagulation, it would be more widely utilized, in food products as well as in many culture mediums for microorganisms or animal cells (tissue culture). We inves-tigated to find the conditions of non-thermal coagulation of egg white. In the preceding paper, the thermal coagulation of egg white was shown to be reduced in salt-free medium. In order to find non-aggregating condition even in the presence of salts, the effect of partial hydrolysis by acid or alkali on thermal coagulation of egg white was studied in this report. When 2 N hydrochloric acid was added to the same volume of egg white solution, protein aggregated immediately and large amount of pre-cipitate was foamed. It was dissolved in limited amounts by continued heating at 100°C for a period of approximately 1 hr. The filtrate being removed the precipitate was not coagulated by heating even in the medium containing of salts, and the medium grew well microorganisms. However, the yield of protein contained in filtrate was low (34%). In the case of addition of 2 N sodium hydroxide to egg solution, protein hardly aggregated and precipitate was rarely found in this solution. After heating stepwisely at 100°C or 120°C for 0 min to 120 min, thermal coagulation test was similarly tried for the filtrate adding salts. The egg white solution did not coagulate at all. Protein in egg white became to be utilized without waste. Furthermore, in non-thermal coagulating protein of egg white, we found it preferable to heat at 120°C for 15 min in 0.1N NaOH solution. However, the egg white medium heated in alkali never grew microorganisms (E. ashbyii). We presumed that some toxins like lysino-alanin appeared by alkali-heating of proteins.