Effect of wheat germ and wheat bran on the fermentation activity, phytic acid content and colour of tarhana, a wheat flour-yoghurt mixture

Tarhana, a dried mixture made from yoghurt and wheat flour, was supplemented with wheat germ/bran to improve its nutritional value. The total titratable acidity (as lactic acid), phytic acid (PA) and colour (Hunter L, a and b values) of tarhana samples were monitored over a three-day fermentation. Titratable acidity of the samples increased sharply during the first day of fermentation and then increased gradually up to the third day of fermentation. Addition of wheat germ/bran to tarhana resulted in increased pH values of the samples. The PA content of tarhana mixture increased as wheat germ/bran amount added to tarhana increased. However, more than 90% of the PA present in the mixtures were inactivated by fermentation. Fermentation caused a decrease in the Hunter L, a and b values giving darker, more green-less reddish and more blue-less yellow samples. (c) 2005 Elsevier Ltd. All rights reserved.