Bulletin #4048, Let’s Preserve: Sweet Corn
Bulletin #4048, Let’s Preserve: Sweet Corn (PDF)
Developed by Penn State Cooperative Extension with special project funds from Extension Service, U.S. Department of Agriculture.
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Some Recommended Varieties
Jubilee, Kandy Korn, and Merit are good yellow varieties. Bodacious and Seneca Horizon are good extra sweet yellow varieties. Butter and Sugar and Twice-As-Nice are good bicolor varieties. Alpne and Silver Queen are good white varieties.
Quantity
A bushel of ears weighs 35 pounds and yields 6 to 11 quarts of whole kernel style, or 12 to 20 pints of cream style corn. An average of 31.5 pounds (in husks) are needed for a 7-quart canner load of whole kernel corn. An average of 20 pounds is needed for a 9-pint canner load of cream style. An average of 2.5 pounds makes 1 pint of frozen whole kernel corn.
Quality
Preserve corn within 2 to 6 hours after harvest for best quality. Select ears containing kernels of ideal maturity for eating fresh. Sweeter varieties may turn brown when canned, especially if processed at 15 pounds of pressure. Can a small amount and check color and flavor before canning large amounts.
Preparation
Husk ears, remove silk, trim out insect-damaged kernels if needed, trim off ends of ears to remove small fibrous kernels, and wash ears. To prepare whole kernel corn for freezing or canning, place ears in one gallon of boiling water and blanch 3 minutes after the water returns to a boil. Cool ears and cut kernels from cob about 3/4 of their depth. Do not scrape the cob. To prepare cream style corn for freezing or canning, blanch ears 4 minutes in boiling water. Cool ears and cut kernels from cob about 1/2 their depth. Scrape the cob with a knife to remove the remainder of the kernels and combine with half-kernels. To prepare corn-on-the-cob for freezing, blanch small ears 7 minutes in boiling water; blanch medium-size ears 9 minutes, and large ears 11 minutes. Cool in several changes of cold water and drain. If desired, cut ears into uniform 4-, 6-, or 8-inch pieces.
Freezing Procedure
Don’t freeze more than 2 pounds of food per cubic foot of freezer capacity per day. To package whole kernel or cream style corn, fill pint- or quart-sized freezer bags to a level of 3 to 4 inches from their tops. Squeeze out air, leave 1-inch headspace, label, and freeze. Before freezing, bags may be inserted into reusable rigid plastic freezer containers for added protection against punctures and freezer burn. To package corn-on-the-cob, fill into quart or half-gallon freezer bags. Squeeze out air, seal, label, and freeze.
Canning Procedure
Wash jars. Prepare lids according to manufacturer’s instructions. Whole kernel corn may be canned in pints or quarts. Cream style corn must be packed in half-pint or pint jars only. If desired, add 1 teaspoon salt per quart, 1/2 teaspoon per pint, or 1/4 teaspoon per half-pint jar. For hot packs, add 1 cup of hot water to each quart of whole kernel or cream style corn in a large pan, and heat to boil. Fill jars with hot corn and cooking liquid, leaving 1-inch headspace. Wipe the sealing surface of jars with a clean, damp paper towel, add lids, tighten screw bands, and process.
To process in a pressure canner, place jar rack, 2 inches of water, and sealed jars in canner. Fasten lids, and heat canner on high setting. After exhausting steam 10 minutes, add weighted gauge or close petcock to pressurize the canner. Start timing the recommended process when the desired pressure is reached.
Process Times
Style of pack | Jar size | Process time (min) | Dial gauge canner | Weighted gauge canner | ||||
|---|---|---|---|---|---|---|---|---|
| Canner gauge pressure at altitudes of | ||||||||
| 0-2000 ft. (lbs.) | 2001-4000 ft. (lbs.) | 4001-6000 ft (lbs.) | 6001-8000 ft. (lbs.) | 0-1000 ft. (lbs.) | Above 1000 ft. (lbs.) | |||
| Hot | Pint | 55 | 11 | 12 | 13 | 14 | 10 | 15 |
| Quart | 85 | 11 | 12 | 13 | 14 | 10 | 15 | |
Style of pack | Jar size | Process time (min) | Dial gauge canner | Weighted gauge canner | ||||
|---|---|---|---|---|---|---|---|---|
| Canner gauge pressure at altitudes of | ||||||||
| 0-2000 ft. (lbs.) | 2001-4000 ft. (lbs.) | 4001-6000 ft (lbs.) | 6001-8000 ft. (lbs.) | 0-1000 ft. (lbs.) | Above 1000 ft. (lbs.) | |||
| Hot | Pint or Half pints | 85 | 11 | 12 | 13 | 14 | 10 | 15 |
Regulate heat to maintain a uniform pressure. When the processing is complete, remove canner from heat. Air-cool canner until it is fully depressurized. Then slowly remove weighted gauge or open petcock, wait 2 more minutes, and unfasten and carefully remove canner lid.
After processing is complete, remove jars from canner with a jar lifter and place on a towel or rack. Do not retighten screw bands. Air-cool jars 12 to 24 hours. Remove screw bands and check lid seals. If the center of the lid is indented, wash, dry, label, and store in a clean, cool, dark place. If the lid is unsealed, examine and replace jar if defective, use new lid, and reprocess as before. Wash bands and store separately. Canned sweet corn is best if consumed within a year and safe as long as lids remain vacuum-sealed.
Nutritional Information
| Raw Sweet | Frozen Kernels Cooked, Drained | Cooked Boiled, Drained | Canned Solids & Liquids | |
|---|---|---|---|---|
| Calories | 66 | 67 | 89 | 79 |
| Carbohydrates, g | 14 | 16 | 20 | 18 |
| Fats, g | 0.9 | 0.06 | 1.0 | 0.5 |
| Protein, g | 2.4 | 2.4 | 2.7 | 2.4 |
| Sodium, mg | 11.7 | 4.0 | 11.7 | 11.7 |
| Vitamin A* | 4 | 4 | 2 | 2 |
| Vitamin C* | 8 | 2 | 8 | 10 |
| Thiamine | 10 | 2 | 10 | 2 |
*Expressed as percentage of the U.S. Recommended Daily Allowances (US RDA). Other vitamins contained at insignificant levels.
Information in this publication is provided purely for educational purposes. No responsibility is assumed for any problems associated with the use of products or services mentioned. No endorsement of products or companies is intended, nor is criticism of unnamed products or companies implied.
© 2000
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