Subjet wort boiling - physical phenomena and technology during heating and boiling phase

摘要

Observations of the classical system in commercial operations at the usual starting temperatures of about 71℃ demonstrate that quite severe pulsations sometimes occur during the heating phase. This leads to thermal damage in wort and to mechanical damage in equipment. Possible solutions to eliminate pulsation hitherto include installation of a pump used for creating flow through the internal boiler, or pre-heating wort to temperatures over 90℃. Both methods involve increased equipment expenditure. This paper deals with mechanisms and origins of pulsation, using a single-tube vaporiser. A comparison is made between the heating characteristics of the conventional system and the subjet system using a pilot-scale wort copper.