Researcher(s)
- Brandon Tang, Mechanical Engineering, University of Delaware
Faculty Mentor(s)
- Juzhong Tan, Animal and Food Sciences, University of Delaware
- Hui Ru Tan, Animal and Food Sciences, University of Delaware
Abstract
Delaware’s cornerstone crop, the lima bean, is a high protein legume with essential minerals which can significantly benefit the human diet, but their main role is currently regulated to livestock feed. Producing puffed snacks from lima bean flour is a method which can increase the crop’s profit for local farms, its value in the state’s economy, and its supplementation in the human diet. The development and optimization of the conditions in which the lima beans puffed snacks are made should be explored to ensure their viability as a commercially produced and sold product. Puffed snacks are produced using a thermal-mechanical process where heated and pressurized material is forced through a compact nozzle to achieve the desired shape and structure, known as extrusion. The extruder is the machine which carries out the extrusion, and consists of several key components with adjustable parameters which can make the difference between the product becoming slop, a puffed snack, or a projectile launched several meters away. Material is first added in at a designated rate at the start of the barrel, the section where the lima bean flour and distilled are mixed together and are pushed through a series of heating zones which can each be set to its own temperature. A set of long rotating twin screws within the barrel are what pushes the substance through while also applying pressure with their rotation speed also being an adjustable parameter. Finally, the mixture is forced through the nozzle which can apply a different amount of pressure and result in a different shape depending on the nozzle dimensions. While determining the ideal processing conditions for the extrusion process may result in a favorable texture/size, to further increase the appeal of the product to the consumer, future research may want to focus on determining compatible flavors.