FUNCTIONAL AND NUTRITIONAL PROPERTIES OF TOMATO PROTEIN CONCENTRATES

Proteins extracted from tomato vines and cannery wastes (TPC) differed substantially in functional properties from soy protein concentrate, but were similar in nutritive value to soy or cottori seed concentrates. When fractionally extracted by precipitation at pH 4.8, 4.0 and 3.5, the fractions had different functional and nutritional properties. The fraction precipitated at pH 3.5 had less coagulated protein, lower foam height, and was less wettable than the fractions precipitated at higher pH, but contained more soluble protein and total solids and a higher bulk density. The pH 3.5 fraction was poorer than the higher pH fractions in all the essential amino acids except lysine. The lower bio-availability of the pH 3.5 fraction was confirmed by bioassays with Tetrahymena pyriformis W.