Rheological characterization of a novel functional food: tomato juice with soy germ

J Agric Food Chem. 2005 Sep 7;53(18):7267-73. doi: 10.1021/jf0511087.

Abstract

The rheological properties of tomato juice containing 1.5% soy germ were compared to plain tomato juice with and without soy protein isolate. This novel product was developed to provide a delivery system of carotenoids, soy protein, and significant isoflavone content without compromising the perceived juice characteristics of tomato product. Rheological tests depicted physical gel characteristics for all three products. Dynamic tests as a function of temperature showed that the stability and the compatibility between tomato juice and soy germ were higher as compared to soy protein isolate. The hydrophobic and electrostatic interactions between pectin and protein in the tomato soy protein isolate system were weakened as the temperature was increased. In the case of tomato juice with soy germ, the viscosity did not change during heating. The addition of soy germ increased the viscosity of tomato juice reinforcing the entire system without major qualitative effects on the rheological properties of plain tomato juice.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Beverages / analysis*
  • Carotenoids / analysis
  • Hot Temperature
  • Isoflavones / analysis
  • Pectins / chemistry
  • Rheology
  • Solanum lycopersicum*
  • Soybean Proteins / analysis*
  • Soybean Proteins / chemistry
  • Static Electricity
  • Viscosity

Substances

  • Isoflavones
  • Soybean Proteins
  • Carotenoids
  • Pectins