EFFECT OF FOAMING AGENT CONCENTRATION AND FOAM STABILIZER ON THE FOAMING CAPACITY AND PHYSICAL PROPERTIES OF TOMATO POWDER AT DRIED AT DIFFERENT TEMPERATURE

Abstract

This study aimed to develop natural colorant tomato powder using foam mat drying method varying egg albumin (3, 5, and 7% w/w) as foaming agent, carboxymethyl cellulose (0.5% and 1%) as foam stabilizer concentrations and dried at three various temperatures (60, 65, and 70 °C). The foaming properties of tomato juice and powder properties of foam mat dried tomato juice powder were analyzed. Foams were prepared using tomato juice, incorporating egg albumin (EA), carboxymethyl cellulose (CMC), and whipped thoroughly at maximum speed for about 5 min. The foam stability and foam expansion were increased from78.4 to 92.1%, and 415.33% to 691.56%while foam density was reduced from 0.2 to 0.139 g/cm3 as air was incorporated into foam. Results showed that 7% egg albumin and 1% carboxymethyl cellulose had good foam expansion, foam stability, and foam density. Among color parameters, redness (a*) increased while lightness (L*) and yellowness (b*) decreased with the increasing temperature. The water solubility index increased from 25.43% to 47.44% with the increasing EA and CMC concentrations and drying temperature. However, the water absorption index decreased with increasing CMC and EA concentrations. The rehydration ratio of tomato powder ranged from 3.22±0.007 and 4.25±0.05 and rose with increasing temperature due to formation of more porous structure. The result showed that 7% EA, 0.5 % CMC concentration, and 70 °C drying temperature of foam produced red colorant tomato powders with good quality characteristics. Obtained powders can be easily converted into juice by reconstitution and used to prepare different value-added products like ketchup, sauce, chutney, etc.