Important: Safety Warning
This page describes home-canning methods from before the causes of botulism were understood. Canning low-acid foods without a pressure canner, as described here, can allow the growth of Clostridium botulinum, whose toxin is among the deadliest known. Follow current USDA home-canning guidelines instead.
This information has been left in for historical purposes but should not be acted upon.
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Sweet Corn
Golden Bantam sweet corn cannot be excelled for canning purposes. The following recipe for canning corn is so satisfactory that no other will be given for this article in these pages.
Have the corn fresh-picked and husked. Use only the pulp, the hull being more difficult to sterilize. To prepare, with a sharp knife score the kernels in each lengthwise row on the ear, then with the back of the knife press out the pulp, leaving the hulls on the cobs. As the pulp expands greatly in cooking, especially at first, the jars should be filled to only two thirds their height. Set the pulp to cook in three jars for each two to be filled. Set the jars in the cooker or canner as usual, the covers beside them; after cooking fifteen or twenty minutes, stir down the corn in each jar and repeat this stirring several times whenever you fear the pulp will rise over the top of the jar. When the corn pulp no longer puffs in cooking, fill two jars from the third and let cook about half an hour, then wipe the top of each jar, adjust the rubber rings and covers, and let cook again about half an hour, then tighten the covers.
Hot water may be used to fill the jars if the quantity of corn pulp is short.
This is a boiling-water method for a low-acid vegetable, and it is the single most dangerous category of home canning. The corn pulp itself is fine food; the process described cannot make it safe to store.
- Why this one failsCorn is low-acid, with a pH around 6.0 to 6.8. Nothing in this recipe brings the jars above the temperature of boiling water, and Clostridium botulinum spores can survive prolonged boiling at 212F. Sealed, oxygen-free, low-acid jars at room temperature are precisely the conditions in which those spores germinate and produce botulinum toxin.
- The "cooker or canner" of 1910The "cooker or canner" -- Household canners of this period were generally open water baths or steam boxes at atmospheric pressure. The total cooking here is roughly an hour and a quarter at boiling. Current tested processes for cream-style corn require a pressure canner holding 240 to 250F for a set time, and no length of boiling substitutes for that pressure.
- Toxin cannot be inspected forBotulinum toxin produces no reliable smell, taste, bubbling or bulge in canned corn. A jar that looks and smells perfect can be lethal, which is why the author's confidence that the method is "so satisfactory" carries no information about safety.
- Open-kettle sealingThe covers are set beside the jars and tightened only after cooking, so the jar rims and rings are exposed to air throughout. This gives a seal without a sterile headspace, and any organism landing on the rim is sealed in with the food.
- No measured quantities or times"About half an hour," "several times whenever you fear" and "hot water may be used" leave the actual thermal process undefined. There is no jar size, no altitude adjustment and no fill weight, so the recipe cannot be reconstructed into anything verifiable.
- If you want canned cornUse a current pressure-canning process from a tested source, or freeze the pulp instead. The scoring-and-scraping technique for cream-style corn described here is sound as knife work and is worth keeping for corn you intend to cook and eat the same day.
Golden Bantam, introduced commercially in the early 1900s, was the variety that did most to persuade American cooks that yellow sweet corn was worth eating at all — before it, yellow kernels were widely thought fit only for livestock, and white corn ruled the table. Home canning books of this period treated corn as the hardest vegetable in the garden, and they were right, though the bacteriology that explained the failures was still being worked out. The pressure canner did not become common household equipment until the 1920s and 1930s, with the U.S. Department of Agriculture pressing the point hard in the following decades. Pages like this one, confident and detailed and quietly lethal, are the reason canning guidance is now issued by extension services rather than left to individual authors.