It was an abrupt and disappointing change when commercial sweet-corn farmers adopted a new type of sweet corn about 15 years ago. Shrewd marketing labeled the new variety of canned and frozen corn "Crisp!", as if that were a desirable characteristic. With about 75 percent more sugars and tougher kernels, "shrunken" or sh2-type sweet corn tolerates more abuse during and after harvest. Farmers appreciate sh2 corn's long harvest window, with sweetness lasting up to 10 days or more past maturity. Plus, sh2's tougher kernels resist bruising during mechanical harvest or rough handling. But true corn aficionados yearn for old-fashioned corn flavor and tender sweet kernels, qualities now found only in home- or locally grown corn.

Heirloom or normal sweet corn is a natural variant of native maize, dent or field corn. Listed in seed catalogs as "su" (the normal sugary type), these varieties may be hybrids or open pollinated. Kernels are very tender and contain moderate amounts of sugars - about 9 percent to 16 percent. Su corn should be picked and eaten as soon as it reaches the milk stage, when kernel juice looks milky white. Soon after maturity, kernel sugar converts to starch and sweetness fades. Common varieties of su corn include Golden Bantam, Silver Queen and Jubilee.

In 1950, an Illinois plant breeder developed the sh2 type of sweet corn. Also called supersweet, sh2 has a sugar content at least double that of normal sugary corn. Conversion of sugar to starch in sh2 corn is much slower than in normal sugary corn, allowing a much longer window of harvest. Kernels are tougher than in normal sugary corn, allowing farmers to harvest mechanically with less injury to the ears. Sh2 varieties ease farm production, but they lack flavor and tenderness preferred by consumers.

About 10 years after sh2's release, another Illinois breeder developed the sugary enhanced (se) type sweet corn. Much more tender than sh2, se has a high sugar content that maintains sweet flavor much longer than su corn. For home gardeners and small-scale production, se varieties offer a good compromise: tender texture with a longer harvest window. Still, many consumers miss the traditional corn flavor.

"Our current consumer society doesn't really know what corn tastes like," says Dan Drost, Utah State University Extension vegetable specialist. "Most of them don't appreciate the differences between the sweet corn from California or Florida and the sweet corn you can buy from local growers."

Drost is a proponent of the Slow Food movement, favoring locally grown produce to fruit and vegetables sold at grocery stores. "So many fruits and vegetables are harvested before they're fully mature so they can be shipped without injury. As a result, we're not satisfied because the flavor can't compare."

To get the best-tasting corn available, Drost buys corn from a local grower only while it's in season. "I don't have enough garden space to grow it myself," he adds.

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* MAGGIE WOLF is an assistant professor for Utah State University Extension in Salt Lake County. E-mail her at maggiew@ext.usu.edu.

For more facts about sweet corn

* USU Extension fact sheet, "Sweet corn in the garden": extension. usu.edu/files/publications/publication/HG Garden 2005-10.pdf

* National Garden Bureau's Sweet Corn Fact Sheet: www.ngb.org/ gardening/fact sheets

* National and Utah Slow Food movement: www.slowfood.com and www.slowfoodutah.org

* CSAs, Community Supported Agriculture in Utah: utahsown.utah. gov/communitysupported agriculture.htm