Ta. Eladawy et Ah. Khalil, CHARACTERISTICS OF ROSELLE SEEDS AS A NEW SOURCE OF PROTEIN AND LIPID, Journal of agricultural and food chemistry, 42(9), 1994, pp. 1896-1900
Chemical composition and nutritional studies of roselle seeds (Hibiscu
s sabdariffa) were performed. The results of amino acid analysis indic
ated roselle seed to be a potential high-protein source. Lysine conten
t was found to be similar to that of the FAO reference protein. The mo
st limiting amino acids in roselle seed were found to be valine, isole
ucine, and tryptophan. Also, the results of lipid analysis indicated r
oselle seeds to be a good source of lipid. Fatty acid analysis reveale
d that linoleic, oleic, palmitic, and stearic acid were the major fatt
y acid constituents. The most predominant inorganic elements in rosell
e seed were found to be K, Na, Mg, and Ca. Roselle seeds exhibited hig
h digestibility by a trypsin-pancreatin system. Analysis of tannins an
d phytic acid in roselle seed revealed low levels. The results of Osbo
rne classification indicated that the major protein fraction consisted
of globulins. Also, roselle protein gave a sharp spectrum with a maxi
mum absorbance at 272 nm. The present study showed that roselle seed p
roteins were highly soluble at acid and alkaline pH values, with a min
imum solubility at about pH 4. Roselle seed meals had excellent foamin
g capacity, foam stability, and water absorption capacity.