Pressure canning potatoes is a great way to preserve an abundant harvest for food storage. The jars of delicious-tasting potatoes are handy for fast additions to meals. Pressure canned potatoes can be used the same way as cooked potatoes, such as pan-fried, mashed, or roasted. For mashed potatoes, reheat them briefly in boiling water, drain, add butter, chives, sour cream, and mash as you would for regular mashed potatoes.

You can also use canned potatoes in chowders, soups, and stews. Since they are already pre-cooked, add the potatoes at the end of your cooking time, so they don’t get too soft.

Pressure canning is the only safe method of canning potatoes. All low-acid foods to be canned must be processed under pressure to destroy Clostridium botulinum spores. Starches slow the transfer of heat to the center of a canning jar; therefore, avoid canning any potato product that would prevent heat transfer during processing. Do not can mashed potatoes, creamed potato soup, or mushy overcooked potatoes that settle to the bottom of the jar. When done correctly, new white potatoes may be safely canned.

Here I will walk through the USDA procedures. When canning new white potatoes, remember:

• Wash hands before and after handling fresh produce.
• Select small to medium-sized (1 to 2 inches in diameter) mature white potatoes. Select potatoes that are firm and free of bruises, nicks, or soft spots.
• Scrub potatoes with a vegetable brush under cool running water. Do not use soap.
• Potatoes must be peeled! Advice to the contrary elsewhere is totally uninformed.
• Tubers stored below 45ºF may discolor when canned.
• Treat potatoes with ascorbic acid to prevent surface darkening (3000 mg or 1 teaspoon to 1 gallon of water) after peeling.
• Potatoes need to be firm enough that they do not become mushy when placed into the jars. There needs to be space between the potato pieces so that water can circulate around the potato pieces while they are being processed.
• For best quality and nutritive value, preserve only what your family can consume in 12 months. 

Yield 

An average of 20 pounds is needed per canner load of 7 quarts and an average of 13 pounds is needed per canner load of 9 pints. A bag weighing 50 pounds will yield 18 to 22 quarts – an average of 2½ to 3 pounds per quart.

How to Preserve

Hot pack method: Bring a pot or kettle of water to a boil. This will be the canning water used to fill the jars. Wash and peel potatoes. Cut into ½ inch cubes, if desired. The recommended shape does not include sliced, French fries shape, nor shredded. Heat penetration patterns were not tested for those shapes and densities. Place in a solution of 1 teaspoon of ascorbic acid and 1 gallon water to prevent darkening. Drain before cooking. Place potatoes in a pot of hot water, and bring to a boil. Boil whole potatoes for 10 minutes; boil cubes for 2 minutes. Drain. Pack hot potatoes in hot jars, leaving 1-inch headspace. Add ½ teaspoon salt to pints and 1 teaspoon to quarts, if desired. Fill jars to 1 inch from the top with fresh boiling water and cover all potato pieces. Caution: Do not use the water you cooked the potatoes in; it contains too much starch. Adjust headspace if needed, remove air bubbles, and wipe jar rims with a clean paper towel. Adjust lids and process jars. See tables for recommended processing times.

Let jars stand undisturbed for 12 to 24 hours, remove rings, wash jars, label, date, and store. Food in jars that did not seal must be reprocessed within 24 hours in a clean jar with a new lid, refrigerated, or frozen.

The tables are from the National Center for Home Food Preservation (NCHFP), Selecting, Preparing and Canning Vegetables: Potatoes, White – Cubed or Whole¸ from the Complete Guide to Home Canning (Agriculture Information Bulletin, No. 539). USDA, revised 2015.

For more detailed information, look at the handy handouts on the UW Extension Nutrition and Food Safety website at https://uwyoextension.org/uwnutrition/category/food-preservation/ or call your local Extension office.

Canning potatoes at home is easier than you think. It’s also the perfect way to preserve fresh potatoes to enjoy all year long.

Written by Vicki Hayman, MS, University of Wyoming Extension Nutrition and Food Safety Educator

Sources:

• www.freshpreserving.com
• http://www.uga.edu/nchfp
• uwyoextension.org/uwnutrition/category/food-preservation