CHARACTERIZATION OF THE FUNCTIONAL PROPERTIES OF PROTEIN ISOLATE FROM MESQUITE BEANS SEED (Prosopis juliflora (SW) D. C.)

Abstract

Protein isolate was prepared from defatted seed of mesquite beans (Porsopis juliflora (SW) D.C.) by alkaline extraction (pH10) and precipitation with hydrochloric acid. In the extraction of proteins from initial samples, 75,0% was extracted and 62.3% was recovered through precipitation. Functional characteristics of protein isolate was studied in terms of terms of solubility water and fat absorption, emulsifying and foaming properties. Protein isolate presented high solubility at acidic and basic pH, except in the pH range between 4 and 6. the water and fat. absorption was possibly influenced by the compact structure of the isolate. The emulsifying capacity was higher at pH 3 and lower at 5. The emulsifying capacity and emulsion stability presented small variations, except at pH 5. The foaming properties depended directly on solubility of proteins. The presence of sodium chloride improved the protein solubility, emulsifying capacity and foaming properties at pH5.