29C-13 |
The effect of flavors on rheological properties of soy flour |
M. E. YILDIZ and J. L. Kokini. Dept. of Food Science, Rutgers, The State Univ. of New Jersey, 65 Dudley Rd., New Brunswick, NJ 08901-8520 Flavors constitute important group of ingredient that require encapsulation. Plasticization can impact the physical properties of a matrix that is used for flavor encapsulation causing an untimely flavor loss and as a result quality loss. The objectives of this study the rheological properties of soy flour as a function of flavor concentration. The glass transition behavior of defatted soy flour was studied as a function of moisture and flavor content using thermal and mechanical analysis. Differential Scanning Calorimetry (DSC) and Advanced Rheometric Expansion System (ARES) were used to determine physical properties such as glass transition temperature, Tg (soy flour matrix with and without flavors). Flavor plasticization was studied at zero moisture content. Six flavors, hexanal, carvone, limonene, octanol, hexyl alcohol and octanoic acid and three commercial flavor blends namely blueberry, strawberry and vanilla, were investigated to determine their effects on the glass transition temperature of soy flour. In addition to water, blueberry, strawberry, vanilla, hexanal, limonene and to a smaller extend carvone and octanoic acid have plasticized the soy matrix. On the other hand octanol and hexanol did not show plasticiztion effects. The knowledge of the effect of flavors on the rheological properties of biopolymers is important in flavor encapsulation. Soy flour has both hydrophobic and hydrophilic groups and results show that both groups play a role in flour/flavor interactions that causes changes in soy flour physical properties.
Session 29C, Food Engineering: Rheology and texture
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