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Understanding and characterizing flake polymorphisms as a quality attribute for microwave popcorn

Jess C Sweley, University of Nebraska - Lincoln


Popcorn (Zea mays everta) is a familiar snack food with sizable commercial popularity. The shape of popped popcorn (i.e., flakes) is a quality factor that has not been comprehensively defined or quantified. Thus, the objective of this work was to investigate the importance of flake polymorphisms in microwave popcorn by (1) identifying and characterizing differences between flake polymorphisms; (2) investigating factors influencing formation of different flake shapes; and (3) determining how flake shape affects consumer acceptability and relates to other quality attributes for popcorn, especially expansion volume. Popcorn flake polymorphisms were identified by visual inspection based on whether appendages were expanded unilaterally, bilaterally, or multilaterally. When popcorn flakes were isolated after microwave popping, it was shown that unilaterally-expanded flakes had the greatest amount of total fat and sodium and highest overall product liking in consumer testing, while multilaterally-shaped flakes had the highest quantities of popcorn-like aromatic pyrazines, lowest content of total fat and sodium, and lowest overall product liking. Formation of different flake polymorphisms is complex and depends on both intrinsic and external factors, as well as interaction effects. Varying the relative proportion of different flake polymorphs in microwave popping is theoretically possible by selecting the optimum hybrids, growing location and environment, corn-oil ratio, and microwave wattage. Empirical modeling revealed both flake size and shape have a significant (p<0.05) effect on expansion volume and popcorn packing characteristics. Bilateral and multilaterally-shaped flakes produce greater expansion volumes than unilateral shapes. In a standard movie-theatre style tub, small unilateral flakes pack together most tightly and require 3x as many pieces to fill the package as large bilateral and multilateral flakes. The results of this research indicate flake polymorphisms are an important quality-attribute for popcorn that can be optimized to support new product development and differentiated usage occasions. The development of new hybrids or techniques to produce popcorn with the most desirable flake shapes can impact both consumer satisfaction and economic profitability for vendors of popped popcorn.

Subject Area

Food Science

Recommended Citation

Sweley, Jess C, "Understanding and characterizing flake polymorphisms as a quality attribute for microwave popcorn" (2012). ETD collection for University of Nebraska - Lincoln. AAI3502358.