Corn is not corn. I know this string is a little old but thought I might jump in here. There are literally hundreds of varieties of corn. Most corn as we know it in this country is #2 yellow. It has a dent in the end of the kernels due to the shrinkage of the starch as it dries. There are all kinds of corn that are known for their color, yellow, white, blue, red, and mixed such as the corn known as Indian corn. There are corns that are grown for their oil, amino acids balance, corn meal for human consumption, corn chips, and taste. There are actually corns that are better suited for ethanol production. They all will react differently to the whiskey making process and they all will produce a different taste in the bottle. There are some distilleries that have their corn grown just for them while others buy on the open market for price alone.
When corn grows sugar is produced by the corn plant and moved into the kernel, where it is converted to starch. If you ever broke a kernel of corn off from the cobb and tasted it; the tip was sweet. All corn starts out as sweet corn. Sweet corn just lacks the ability to convert the sugar to starch. When we make alcohol from corn we first have to convert the starch back to the sugar. In sweet corn the sugar was never converted to starch so that step is not necessary. Commercial sweet corn you buy in the can is not like the sweet corn you buy in the farmers market. In my opinion it is very difficult to harvest the kernels from garden varieties of sweet corn so commercial sweet corn that is canned needs some converting prior to yeast. Sweet corn makes good whiskey but keep in mind there are many different varieties of sweet corn and they all will need somewhat different processing. Our normal #2 yellow corn makes cheap whiskey and needs the help of a good barrel to take out the harshness that is produced. This corn has been selected for generations on its ability to produce the maximum yield per acre. It is mostly fed to cows, hogs, or ethanol plants. Blue corn however has been consumed by humans directly and has been selected for taste over many generations. It has a great taste (compare blue corn chips to regular corn chips) but has a poor yield. It also makes great tasting whiskey. The cost of blue corn will be higher but really the cost of corn in craft whiskey is not significant compared to other costs. After all we as craft distillers are selling taste. There are some great tasting corns out there. It is the diversity that we craft distillers bring to the table. Corn offers that diversity and we should be spending major time in selecting that special corn with that unique flavor because the majors cannot compete with us on this aspect. And by the way I do have some blue corn seed for sale for anyone that wants to grow their own.