Particle Size Distribution and Viscoelastic Behavior of French Dressing Containing Two Types of Commercial Waxy Maize Starches

Emulsion stability, viscoelastic rheological properties and particle size distribution of French dressing samples formulated with two types of commercial modified starch have been investigated. The product’s usual thickening agents, xanthan and guar gum, were 100% substituted by (2, 2.2%) of acetylated distarch adipate (ADA) and hydroxypropylated distarch phosphate (HDP) from waxy maize starch. The samples with 2% hydroxypropylated distarch phosphate starch showed the minimum emulsion stability (<95% after three months of storage) and were eliminated from further studies and the other three samples along with the control were selected for particle size distributions and dynamic rheological properties analysis. The sample formulated with 2.2% of HDP starch showed a better storage stability (higher zero shear viscosity), deformability (γLVE) and greater texture strength (G’0) due to more structural entanglement and  intermolecular hydrogen bonds as compared to the other type of commercial starch and control. In particle size distribution curve of this sample a broad and distinguished peak with higher percentage of population ranging from 10 to 100 µm was observed which might be due to the higher water absorption and more swollen/degraded starch granules. The area-based average diameter (d3,2) of the particles confirmed more similarity between this sample  and control.