Effects of hybrid, environment, oil addition, and microwave wattage on popped popcorn morphology

The objective of this study was to understand what factors influence the formation of different shapes of popped popcorn through the development of statistical models. Microwave popcorn popping was conducted across a range of microwave wattages (750-1240 W) and oil additions (0-30%) using a set of three popcorn hybrids grown in three environments. After popping, expansion volume was measured and the relative proportion of different popped shapes was enumerated by visual characterization of popped flakes, namely: unilateral, bilateral, or multilaterally expanded. The percentage of flake morphologies varied from 1 to 24% unilateral, 20 to 55% bilateral, and 31 to 68% multilateral across all runs. The relative percentage of each shape was influenced by hybrid, growing location, corn:oil ratio, and microwave wattage. The proportion of unilateral flakes was positively correlated to oleic acid in the kernel and negatively correlated to kernel sphericity, while bilateral flakes were positively correlated to dietary fiber in the kernel. Expansion volume was positively correlated to occurrence of bilaterally expanded flakes and negatively correlated to unilateral shape. These data may support the development of new hybrids or varieties of popcorn that produce the most desirable amounts of popped shapes in order to optimize consumer liking or create differentiated products and market new usages for popcorn.

► Popcorn shape was influenced by extrinsic and intrinsic factors. ► Shape varied from 1-24% unilateral, 20-55% bilateral, and 31-68% multilateral. ► Expansion volume was negatively correlated to unilateral shape. ► Expansion volume was positively correlated to bilateral shape.