You may can your own corn at home, free of added salt and preservatives. And unlike store brands, you don’t have to pay extra to leave the bad stuff out!
Traditionally people have started from fresh corn. But if you find a super special on frozen corn and don’t have the freezer space, you can can that, too!
Did you know that our spelling of corn kernels comes from the old spelling of the word Korn?
Quantities of corn needed
Numbers are approximate guidelines.
Fresh corn on the cob
On average, as a very rough guideline, expect to need about 2 kg (4 1/2 lbs / about 8 medium cobs) of corn on the cob per 1 litre (US quart) jar of canned corn
- 14 kg (31.5 lb) of corn on the cob = 7 litres (US quarts) canned corn
- 9 kg (20 lbs ) of corn on the cob= 9 x half-litres (US pints) canned corn
- 1 US bushel corn on the cob = 16 kg (35 lbs) = 6 to 11 litres (US quarts) canned corn
A medium-sized cob of corn is about 20 cm (8 inches) long, excluding the stalk, about 5 cm (2 inches) at its widest, and, weighs around 1/4 kg (1/2 lb).
Frozen corn kernels
As a rough guideline, you’ll need about 300 g (10 oz in weight) of frozen corn kernels per 1/2 litre (1 US pint) jar
- 2 kg (4 1/2 lbs) corn kernels = 7 x half-litre (1 US pint) jars
Jar size choices: Either half-litre (1 US pint) OR 1 litre (1 US quart)
Processing method: Pressure canning only
Headspace: 3 cm (1 inch)
Processing pressure: 10 lbs (69 kPa) weighted gauge, 11 lbs (76 kpa) dial gauge (adjust pressure for your altitude when over 300 metres / 1000 feet)
Processing time: Half-litres (pints) 55 minutes; litres (quarts) 85 minutes
Serving size: 175 g (1 cup)
Fat: 1.0 g
- Fresh corn: husk and silk corn, then wash. Put the cobs in a large pot of water, bring to a boil and boil 3 minutes. Scrape kernels off going about ¾ of the way down into the corn, without scraping the actual cob.
- Frozen corn: If using frozen, empty bag into a large microwave-safe jug or bowl with approx 1 cup ( 8 oz / 250 ml) of water, cover and zap for 7 minutes. Drain well.
- However you obtained the corn kernels, for each 500 g / 1 pound / 1 litre / 1 quart of corn kernels, put in a large pot with 250 ml (1 cup) of water. Bring to a boil, then lower to a simmer and let simmer for 5 minutes.
- Pack loosely into half-litre (US pint) jars or 1 litre (US quart) jars.
- Leave 3 cm (1 inch) headspace.
- Top up with clean boiling water (such as from a kettle, for instance), maintaining headspace.
- Debubble, adjust headspace.
- Wipe jar rims.
- Put lids on.
- Processing pressure: 10 lbs (69 kPa) weighted gauge, 11 lbs (76 kpa) dial gauge (adjust pressure for your altitude when over 300 metres / 1000 feet)
- Processing time: half-litre (US pint) jars for 55 minutes OR 1 litre (US quart) jars for 85 minutes.
Processing guidelines below are for weighted-gauge pressure canner. See also if applicable: Dial-gauge pressures.
|Jar Size||Time||0 to 300 m (0 - 1000 feet) pressure||Above 300 m (1000 ft) pressure|
|1/2 litre (1 US pint)||55 mins||10 lbs||15 lb|
|1 litre (1 US quart)||85 mins||10 lbs||15 lb|
Note that the USDA also offers a raw-pack procedure which lets you fill the jars with raw kernels straight off the cobs. (Hot packs though are generally considered to offer superior storage quality.)
How to pressure can.
When pressure canning, you must adjust the pressure for your altitude.
More information about Salt-Free Canning in general.
- If starting from frozen, the corn should be totally thawed coming out of the microwave. It doesn’t need to be cooked; just, you want no frozen bits left, so that you are achieving the equivalent of starting from warmed fresh, which is what the tested procedure was based on.
- The book, So Easy to Preserve, says, “Corn, peas and lima beans are starchy and expand during processing. They should be packed loosely.”1
Corn – Whole Kernel. United States Department of Agriculture (USDA). Complete guide to home canning. Agriculture information bulletin No. 539. 2015. Page 4-11.
To be clear, the USDA does not have a procedure for starting from frozen. Completely thawing frozen corn and then proceeding with their procedures should be an equivalent. For Cooperative Extension Service advice on canning previously frozen food, see: Can your freezer.
Home-canned corn turning brown
On its blog, the National Center for Home Food Preservation says this:
If your corn browns during canning, it usually means that the temperature required for canning is too high for the sugar levels in your corn variety. This carmelization has become more of a problem as newer varieties of corn get sweeter and sweeter. You cannot safely reduce the heat or processing time needed for canning corn; you can freeze that corn or find a locally grown variety that is recommended for canning. Though not an immediate safety concern, you might want to consider refrigerating these jars and/or consuming them more quickly since they may not maintain the best quality for long.2
Serving size: 175 g, drained (1 cup)
Per 175 g / 1 cup:
- 124 calories, 2 mg sodium
- Weight Watchers PointsPlus®: 4 points
* Nutrition info provided by http://caloriecount.about.com
* PointsPlus™ calculated by healthycanning.com. Not endorsed by Weight Watchers® International, Inc, which is the owner of the PointsPlus® registered trademark.