Fat-free yoghurt was made by replacing buffaloe's skim milk with sweet buttermilk at the rate of 25, 50, 75
and 100%. Resultant yoghurt was stored at (6±1˚C) for 12 days. The effects of different levels of buttermilk on the
chemical, rheological and sensory quality of fat-free yoghurt were followed. The total solids of fat-free yoghurt were
significantly reduced as compared to control full fat yoghurt as a result of skimming. There were a significant effect on
fat content of yoghurt during the storage period, While no significant (p<0.05) differences among the fat-free treatments
were observed. Using buttermilk did not affect significantly acidity and pH values. Replacement of buffaloe's skim milk
by sweet buttermilk caused a significant increase in acetaldehyde and diacetyle content as compared with control fatfree
yoghurt. It was noticed that replacing of buffaloes' skim milk with different ratios of buttermilk caused reduction of
syneresis compared to control fat-free (T2). Using buttermilk with different ratios reduce the firmness of the fat-free
yoghurt significantly (p<0.05) as compared to full fat yoghurt. Replacing buffaloes' skim milk with sweet buttermilk
affect significantly (p<0.05) the viscosity and increased consistency of fat-free yoghurt as compared with control fatfree
yoghurt (T2). Fat- free yoghurt manufacture by replacing buffaloes' skim milk with sweet buttermilk up to 50%
gained higher scores for flavour, body & texture and the total score than control fat-free yoghurt (T2). It could be
concluded that, fat-free yoghurt made with 50% sweet buttermilk as a replacement of buffaloe's skim milk exhibited
creamy mouth feel, homogenous good texture and perceived overall-acceptability among the experimental fat-free
yoghurt, and were quite similar to that of full-fat yoghurt.