Among the tested sensory characteristics, taste received the
lowest scores for all preparations. Colour and appearance of the yogurt
samples was scored most highly for all four preparations,
while among the various preparations addition of 10% fruit juice
resulted in the highest scores for overall sensory attributes. The
major end products of propionic fermentation are propionic, acetic,
succinic acids and carbon dioxide. In Swiss-type cheese manufacturing,
presence of propionibacteria plays a major role in creation
of characteristic holes/eyes due to carbon dioxide release. Although
some strains of propionibacteria show metabolic activities at low
temperatures, their activities under these conditions may not generally
lead to a sufficient rate of gas formation to create holes. In this experiment, eye
formation or changes in structure and appearance was not recorded
in any preparation. Ekinci and Gurel (2008) also reported
the possibility of incorporation of propionibacteria in yogurt production,
without adversely affecting the structural properties of
cow’s milk yogurt.