MICROBIOLOGICAL ASPECTS OF ERGO (ITITU) FERMENTATION

Abstract

Ergo is a traditionally fermented dairy product which has some
resemblance to yogurt in its curd formation and acidity. Raw milk is allowed to ferment in to Ergo for about 24 h at ambient temperature before it is consumed. Time course studies on growth of the microorganisms involved in the fermentation of Ergo were made. Its fermentation is carried out by lactic acid bacteria belonging to the genera LaclococCUS, Streptococcus, Leuconostoc and Lactobacillus. However, micrococci, sporeformers and coliforms were present
in fairly high numbers during the first 14-16 h of fermentation. The Lactococci were the most dominant group throughout the fermentation (1 x 1 (j" at time 0 hand 4x 109 colony forming unit cfu(ml)"l at end of fermentation (24 h), followed by Streptococci. The yeast population which was about Ix 101 cfu(ml)"1 just after milking increased to about Ix lOS cfu(mlr' at the end of 24 h of fermentation. The total aerobic mesophilic count (TAM) increased from about b10s cfu(ml)"' to
4x 109 cfu(ml)"l and at the same time titratable acidity increased from 0.16 to 0.75 % with concomitant drop in the pH.