In some forums, there is actually quite a debate about how long to boil corn.
According to Betty Crocker's Cookbook: "Place corn in enough unsalted cold water to cover (salt toughens corn). Add one tablespoon sugar, and one tablespoon lemon juice to each gallon of water. Heat to boiling; boil uncovered two minutes. Remove from heat; let stand 10 minutes before serving."
I believe that when it says "Remove from heat; let stand 10 minutes before serving", it means to take the corn out of the water and let it stand for 10 minutes, not to just remove the pot from the heat and let the corn stand in the water for 10 minutes.
According to What Mrs. Fisher Knows About Old Southern Cooking (Classic Reprint): "Always put the corn on in boiling water and salt, cooking for seven minutes; a longer cooking than this will take all the sweetness from the corn."
Just bring the corn to a boil, and it is done. This method gives you the freshest sweetest tasting corn. When I boil corn on the cob, I bring the water to a boil, drop the ears of corn in, cover my pot, and then bring the water back to a boil again. Once it comes back to a boil, it is done! Remove the corn to a serving platter.
Corn has various natural simple sugars in it that convert to starches as the corn ages, or after it has been picked. It turns out that corn has some enzymes that are involved in this conversion process, and they are hastened on their way by exposure to heat (heat acts as a catalyst), so longer cooking times result in more sugars being converted to starches, and corn that is not as sweet.
If you want to eat the freshest corn then Grow Your Own Corn is a site that gives information about when to plant and what the different varieties are. If I had a garden, I'd try growing Spring Snow (white), Precocious (yellow), or Quickie (bi-color).
This site is protected by copyright and trademark laws under US and International law. © 2002-2015 M. Craig Weaver All rights reserved.
Rendered: Wednesday November 25 2015
My opinions are not regulated by any recognized authority - I am neither competent nor authorized to dispense advice of any kind. It is probably best to ignore me.