Onions: Those versatile edible bulbs

Pressure canning onions prevents botulism poisoning.

Historically it is believed that the onion was first cultivated 5000 years ago by the Chinese. In Egypt, onions were considered an object of worship because the concentric layers of the onion reminded the Egyptians of eternity. In the Bible, Numbers 11:5, the Israelites lament about their meager diet containing onions, while in exodus from Egypt.

By the Middle Ages, there were three main vegetables in the European cuisine, which were beans, cabbage, and onions. Onions were used for medicinal reasons too. When the Pilgrims came to America, they brought with them bulbs of onions, but soon discovered that wild onion strains populated North America. The Pilgrims discovered the Native Americans used onions in a variety of ways, such as eating them raw or cooked, as a seasoning, or as a vegetable.

In 1648 the diaries of the Pilgrims documented that as soon as the land was cleared enough to plant, onions were one of the first crops planted.

Today, onions are used in a variety of ways in cooking, such as sautéed, boiled, grilled, or as a seasoning. Onions vary is color, flavor, size and time of year that they are harvested. These differences make onions one of the more versatile vegetables.

Onions come in yellow, red, and white. In the United States 87 percent of the crop production is devoted to the yellow onion, while eight percent is devoted to red onions and five percent goes to white onions.

Onions are seasonal. There are two basic seasons. Spring/summer onions are available March through August. Their flavor ranges from sweet to mild. Fall/winter onions are available August through May. In Michigan the harvest is for fall/winter onions. Michigan grown onions are available from September to March. The flavor of the fall/winter onions ranges from mild to pungent. 

For storage of bulb onions, store them in a cool, dry place. Ideal conditions for storage would be temperatures between 35-55 degrees Fahrenheit with 50 to 60 percent humidity. With these conditions, onions should store for one to eight months.

Onions can be preserved by freezing canning, pickling, and dehydration. For freezing remember onions that have been frozen will only be suitable for cooking.

Michigan State University Extension recommends that you wash your hands before preparing any fresh produce. The fresh produce needs to be rinsed well with lukewarm water before any further preparation takes place.

If chopped onions are being frozen, they do not need to be blanched. Simply chop the onions in amounts desired for a recipe, seal, label, and freeze in either rigid containers, leaving a ½ inch headspace or plastic freezer bags.

If bulb onions are desired, choose mature bulbs that are cleaned as though they were going to be eaten raw. Blanch the whole mature bulbs in boiling water for 3 to 7 minutes. Cool immediately in ice water to stop the cooking action. Drain and package. If using a rigid container, leave ½ inch headspace. Seal, label, and freeze the onions.

Since onions are a vegetable, they MUST be pressure canned to avoid the potential of botulism poisoning.

To can onions, select onions that are 1-inch in diameter or less. Wash and peel the onions. Use the hot pack technique of canning the onions. Cover the onions with boiling water; bring to a boil; and boil for five minutes. Pack the hot onions into clean, hot jars, leaving a 1-inch headspace. It is optional to add salt to the onions. If salt is desired, add ½ teaspoon of salt to pints or 1 teaspoon of salt for quarts. Pour boiling water into the jar, leaving a 1-inch headspace. Remove the air bubbles. Wipe the jar rims with a paper towel or a clean cloth. Adjust the lids and process.

Recommended process time for onions in a dial-gauge pressure canner at different altitudes.

Jar size

Process time (min.)

0-2,000 ft.

2,001-4,000 ft.

4,001-6,000 ft.

6,000-8,000 ft.

Pints

40 

11

12

13

14

Quarts

40

11

12

13

14

Recommended process time for onions in a weighted-gauge pressure canner at different altitudes.

Jar Size

Process time (min.)

0-1,000 ft.

Above 1,000 ft.

Pints 

40

10

15

Quarts

40

10 

15

For pickle onion recipes check out the “So Easy to Preserve” bulliten by the University of Georgia. 

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