THE EFFECT OF SOME PROCESSING METHODS ON THE FLATULENCE FACTOR IN SOME COWPEA VARIETIES (Vigna unguiculata (L) Walp
THE EFFECT OF SOME PROCESSING METHODS ON THE FLATULENCE FACTOR IN SOME COWPEA VARIETIES (Vigna unguiculata (L) Walp
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Date
1998-05
Authors
NJOKU, GODWIN CHIAKA
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Abstract
Oligosaccharide contents of 5 cowpea varieties were
studied in raw and processed samples. Thin layer
chromatography of 80% ethanol extracts of the defatted samples
revealed the presence of verbascose, stachyose, raffinose,
sucrose and in some cases, traces of glucose- Quantitative
analysis using phenol-sulphuric acid assay method revealed
that the average content of the oligosaccharides in whole raw
cowpea were raffinose 1.19g/100g and stachyose 3.88g/100g with
no varietal difference in the levels of raffinose. Stachyose
levels showed difference due to variety.
The results showed a steady decrease in raffinose and
stachyose contents in the order-dehulling, cold water soaking,
cooking, processing into bean cake, alkali (potash) treatment
and hot water soaking (blanching).
Dehulling resulted in a mean reduction of 30.25% for
raffinose and 26.80% for stachyose while cold water soaking
for 16hrs gave a mean reduction of 40.34% for raffinose and
35.29% for stachyose. Cooking for 40mins was sufficient to
promote a mean reduction of 47.06% for raffinose and 36.85%
for stachyose. Mean reduction of 47.90% for raffinose and
47.16% for stachyose were obtained when the cowpea was
processed into bean cake. Alkali (potash) treatment reduced
the mean raffinose level by 68.90% and 61.34% for stachyose.
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Hot water soaking for 4 hrs brought about a mean decrease
of over 80% for both raffishness and stachyose which when
analyzed gave an equivalent of about 82.2% reduction of
flatulence activities.
Statistical analysis at (P < 0.05) also showed that
processing time and treatment (processing method) were more
important factors affecting the levels of the oligosaccharides
than variety.
Description
A THESIS SUBMITTED TO THE POSTGRADUATE SCHOOL, AHMADU BELLO
UNIVERSITY, ZARIA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE AWARD OF MASTER OF SCIENCE (M.Sc) DEGREE IN
BIOCHEMISTRY
DEPARTMENT OF BIOCHEMISTRY
FACULTY OF SCIENCE
AHMADU BELLO UNIVERSITY
ZARIA, NIGERIA
MAY 1998
Keywords
EFFECT,, PROCESSING,, METHODS,, FLATULENCE,, FACTOR,, COWPEA,, VARIETIES,, (Vigna unguiculata),, (L) Walp)