Academic Journals Database
Disseminating quality controlled scientific knowledge

Composition and Functional Properties of Cowpea (Vigna ungiculata L. Walp) Flour and Protein Isolates

Author(s): I.I. Khalid | S.B. Elhardallou | E.A. Elkhalifa

Journal: American Journal of Food Technology
ISSN 1557-4571

Volume: 7;
Issue: 3;
Start page: 113;
Date: 2012;
VIEW PDF   PDF DOWNLOAD PDF   Download PDF Original page

Keywords: Cowpea | functional properties | protein isolate

Protein isolates from dehulled defatted cowpea (Vigna ungiculata L.) seeds were prepared using isoelectric (CPIA) precipitation and micellization (CPIB) procedures. Proximate analysis gave 75% crude protein, 2.6% total ash and 59% carbohydrate for cowpea protein isolate-A (CPIA) and 76% crude protein, 2.3% total ash and 13.1% carbohydrate for Cowpea Protein Isolate-B (CPIB).The protein percentage of the seed was found to be 22.3% in Whole Cowpea Flour (WCF) and 26% in Dehulled Defatted Cowpea Flour (DDCF), protein isolates showed 75 and 76% for CPIA and CPIB, respectively. The minimum protein solubility for CPIA was at pH 5.0 and for CPIB at pH 4.0. Total protein isolate studied showed good solubility in both acid and alkaline pH regions. For water and oil absorption capacity, DDCF gave 1.3 mL water g-1 sample and 1.04 mL oil g-1 sample, respectively; while CPIA gave 2.10 mL water g-1 sample and 1.93 mL oil g-1 sample, CPIB gave 2.33 mL water g-1 sample and 2.37 mL oil g-1 sample. Thus CPIA and CPIB showed better performance than DDCF with respect to these properties. The highest Emulsifying Capacity (EC) was observed at pH 12.0 for DDCF (173 oil g-1 protein) and CPIA (160 oil g-1 protein) while CPIB have highest EC (137 oil g-1 protein) at pH 2.0 The emulsion capacity for both cowpea protein isolates (CPIA and CPIB) was higher at pH 7.0 compare to value obtained from DDCF. Least gelation concentration for Dehulled Defatted Cowpea Flour (DDCF) and both Cowpea Protein Isolates (CPIA) and (CPIB) was noted at 12.0% (w/v) at both pH 4.0 and 7.0.

Tango Jona
Tangokurs Rapperswil-Jona

     Save time & money - Smart Internet Solutions