[Study] of popcorn

Popcorn

P.R. Carter¹, D.R. Hicks², J.D. Doll¹, E.E. Schulte¹, R. Schuler¹, and B. Holmes¹

1Departments of Agronomy, Soil Science and Ag. Engineering. College of Agricultural and Life Sciences and Cooperative Extension Service, University of Wisconsin-Madison, WI 53706.
²Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108. Nov. 1989.

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I. History:

Popcorn is a special kind of flint corn that was selected by Indians in early western civilizations. Although U.S. commercial popcorn production has always been centered in the Corn Belt, the major growing areas within this region have shifted over the years. Up to the mid 1940s, Iowa was the number one producer, with both production and processing plants concentrated in the western part of the state. Then, as popcorn hybrids began replacing open-pollinated varieties, production shifted eastward, first to Illinois and then to Indiana. Another major shift occurred in the mid 1970s when production jumped back to the west, so that Nebraska is now the leading popcorn producer.
Total U.S. popcorn acreage over the 5-year period 1977-81 averaged 189,000 acres per year, with 55% of that total in Nebraska and Indiana, and another 25% in Iowa, Ohio and Illinois.

II. Uses:

Popcorn is sold either as a plain or flavor-added popped product, or as an unpopped product in moisture-proof containers ranging from plastic bags and sealed jars to ready-to-use containers both for conventional and microwave popping. Popcorn flavor is enhanced to individual tastes with the addition of salt and butter. There is no end to the uses of popcorn. One recipe book lists 200 different recipes.
Nutritionally, it is one of the best all-around snack foods, providing 67% as much protein, 110% as much iron and as much calcium as an equal amount of beef. An average 1.5-ounce serving of popcorn supplies the same energy as two eggs; and a cup of unbuttered popcorn contains less calories than half a medium grapefruit. In addition, hull is excellent roughage, comparing favorably with bran flakes or whole wheat toast.

III. Growth Habits:

Popcorn moves through commercial channels primarily in three kernel types: white, small yellow and large yellow. White popcorn characteristically has a rice-shaped kernel, while yellow popcorn kernels are pearl-shaped. The three kernel types meet different needs within the industry, and growers and/or processors must take that into consideration when selecting hybrids. Kernel color of specialty popcorn may also be blue, red, black, or brown.
The popped appearance may resemble either a butterfly or a mushroom. The butterfly type is preferred for eating; while the mushroom type is used in confectionery products.
In performance trials, a hybrid is usually identified as one of the above types, although some medium-kernel yellows are now available that meet either the small- or large-kernel requirements after grading. No industry standards have been developed for kernel size determinations; but a commonly used measure is based on number of kernels in 10 grams and defines kernel size as follows:52-67 = large, 68-75 = medium and 76-105 small.
Popcorn hybrids generally have smaller plants and about 2/3 the yield per plant than dent corn. Stalk strength is relatively poor compared to dent corn hybrids.