Table 6. Diacetyl content (mg/L) of drinking yogurt samples during cold storage (mean±SD)

Sample	First day	11th day	21th day
C	0.44±0.08Cb	0.50±0.08Bb	0.71±0.08Ab
FE250	0.63±0.08Ca	0.66±0.08Bab	0.93±0.06Aa
FE500	0.61±0.11Ca	0.72±0.11Ba	0.91±0.08Aa
IE250	0.63±0.09Ca	0.65±0.08Bab	0.90±0.09Aa
IE500	0.60±0.12Ca	0.73±0.08Ba	0.91±0.07Aa

Values in the same column shown with similar lowercase letters are not significantly different.
Values in the same rows shown with similar capital letters are not significantly different.