Automatic method to quantify starter activity based on pH measurement

Abstract

Summary A new method for measuring the activity of mesophilic and thermophilic lactic acid bacteria is proposed based on measuring the pH of cultures at extremely short intervals (30–90 s) during growth and calculating several kinetic parameters, i.e. the maximum acidification rate (V m ), the time and pH at which V m occurred, the time or pH range during which the observed rates were greater than V m /2. These were easily calculated by coupling the pH meter to a microcomputer.