Project Description

Starch pasting is the process by which starch granules uptake water in a heated aqueous medium and thicken a starch dispersion. This process is common in a variety of products (food, paper coating to the fabrication of paints) in order to produce a given texture. There is a lack of reliable, physics-based models to predict the rheology of starch suspensions that can be used to tailor processing conditions for a given texture. This would require understanding the swelling of starch granules, and its effect on the rheology of suspension. The first part of the project will refine existing model for swelling of starch granules to account for different ingredient interactions on evolution of granule size distribution. The second part of the project will incorporate this information in the prediction of rheology of starch paste using Stokesian dynamics simulation (below jamming limit) and foam models (beyond jammed limit). Experiments will validate these predictions by characterizing the shear rheology, granule size, and morphology of starch suspensions for a wide range of heating rates, starch varieties and ingredient interactions. These results will provide rational guidelines for industry to tailor the functionality of starch-based materials for a wide range of applications.

Start Date

April 2020

Postdoc Qualifications 

The postdoctoral researcher should have a degree in Chemical Engineering, Mechanical Engineering, Materials Science, or equivalent. The research requires a strong background in fluid mechanics and rheology. Experience in computational fluid dynamics and colloidal/interfacial science is desirable. 

Co-advisors 

Vivek Narsimhan
vnarism@purdue.edu
Assistant Professor of Chemical Engineering
https://engineering.purdue.edu/ChE/people/ptProfile?resource_id=169352

Ganesan Narsimhan
narsimha@purdue.edu
Professor of Agricultural and Biological Engineering
https://engineering.purdue.edu/ABE/people/ptProfile?resource_id=7368

References 

Desam, G. P., J. S. Li, G. B. Chen, O. Campanella and G. Narsimhan (2018a). "A mechanistic model for swelling kinetics of waxy maize starch suspension." Journal of Food Engineering 222: 237-249.

Desam, G. P., J. S. Li, G. B. Chen, O. Campanella and G. Narsimhan (2018b). "Prediction of swelling behavior of crosslinked maize starch suspensions." Carbohydrate Polymers 199: 331-340.

A. Gupta, V. Narsimhan, T.A. Hatton, and P.S. Doyle. “Kinetics of change in droplet size during nanoemulsion formation” Langmuir, 32, 11551-11559, (2016)

V. Narsimhan. "Shape and rheology of droplets with viscous surface moduli." J. Fluid Mech., 862, 385-420, (2019).