ANTI-NUTRITIONAL CONSTITUENT OF COLOCASIA ESCULENTA ...

Phytochemical screening was carried out to determine the presence of flavonoids in the
Amadumbe tubers. Yellow colouration was observed, indicating the presence of
flavonoids (Figure A3-2) (Boham and Kocipai-Abyazan (1974)]. Flavonoid content
decreased during processing, as can be seen in the difference in colouration observed
between the screened processed and unprocessed samples (Figure A3-2).
EW EP MtW MtP MakW MakP BW BP RW RP FW RP
Figure A3-2: Phytochemical screening for flavonoids in the unprocessed (left)
Key
EW - Esikhawini white
MtP - Mtubatuba Purple
BW - Boiled White
RP - Roasted Purple
and processed (right) tubers
EP - Esikhawini Purple
MakW - Makatini White
BP - Boiled Purple
FW - Fried White
MtW - Mtubatuba White
MakP - Makatini Purple
RW - Roasted White
FP - Fried Purple
The total flavonoid content of the unprocessed and processed tubers was then quantified.
Unprocessed flavonoid content ranged from 0.03 to 0.049 mg/g of dry matter and that of
processed tubers, frOID 0.01 to 0.009 mg/g (Table A3-4b).
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