Paper Number
AR1
Session
Applied Rheology for Pharmaceuticals, Food, and Consumer Products
Title
Using rheology to optimize of the chocolate process
Presentation Date and Time
October 23, 2019 (Wednesday) 9:50
Track / Room
Track 6 / Room 306B
Authors
- Boylston, Payton (United States Military Academy, Chemistry and Life Science)
- Miller, April (United States Military Academy, Chemistry and Life Science)
- Schieve, Bailey (United States Military Academy, Chemistry and Life Science)
- Armstrong, Matthew J. (United States Military Academy)
Author and Affiliation Lines
Payton Boylston, April Miller, Bailey Schieve, and Matthew J. Armstrong
Chemistry and Life Science, United States Military Academy, west point, NY 10996
Speaker / Presenter
Boylston, Payton
Text of Abstract
The science behind why some chocolates are more appealing than others is based on the optimization of the entire chocolate-making/production process. This process involves cocoa nib processing, mixing, refining, tempering and molding. Proper parameters, such as conch/melanger timing, seed chocolate and temperature, will affect the final taste. Since the appeal of chocolate is based on the chocolate’s balance of viscous and elastic behavior, comparing physical properties evaluated from rheological studies can determine the optimal procedures. The Casson model is commonly used to model food dispersions and is commonly used in chocolate manufacturing. The Casson parameters, Casson yield stress and Casson plastic viscosity, define the characteristic chocolate texture and flavor. The Casson yield stress is the minimum stress required to initiate the flow and marks the transition from the solid viscoelastic stage to the liquid stage [1,2,3]. The Casson plastic viscosity is the resistance to flow. These parameters are identified by fitting the Casson Model parameters to the steady state flow curve. Chocolate is a complex multiphase material and the transition from a solid to liquid depends on its evolving, stress dependent microstructure [3,4]. In this study, more contemporary thixo-elastic-visco-plastic (TEVP) rheological models are compared to the traditional steady state Casson model. The TEVP models fit steady and transient data, with a yield stress and plastic viscosity parameters to be compared to the Casson parameters. This research highlights the tempering and refining of the United States Military Academy chocolate making process. Chocolate tempering and refining techniques are studied to determine the impact on the chocolate’s complex behavior, yielding optimal rheological parameters.