Canning might in fact be one of the best way to store sweet potatoes. They hate being refrigerated, preferring a dark cellar around 13 C (55 F), which not many people can supply any more. They can be successfully frozen for up to 6 months, after being partly cooked first. But only canned sweet potato has a longer guaranteed storage life, and lets you decide on the spur of a moment to have them for supper.
You need around 1 kg (2.25 lbs) per 1 litre (1 US quart) jar.
In 1930, the Ball Blue Book advised that “some of the best varieties for canning are the Nancy Hall, Triumph and Southern Queen.”1 While supermarkets will never be able to tell you what variety they are selling you, those able to try their hand at growing their own might be able to procure those varieties.
Jar size choices: Either 1/2 litre (1 US pint) OR 1 litre (1 US quart)
Processing method: Pressure canning
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) 65 minutes; litres (quarts) 90 minutes.
Serving size: 250 g
- Sweet potatoes
- Wash potatoes. Leave skins on.
- Boil or steam in their skin until a bit soft. This should take 15 to 20 minutes, depending on how big they are, and how many you have in the pot at once.
- Let cool until you can safely handle them.
- Peel; discard peel (or reserve for another non-canning use such as stock).
- Chop into roughly 3 cm (1 inch) cubes.
- Pack 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 65 minutes OR 1 litre (US quart) jars for 90 minutes.
Mashing the sweet potato is unsafe; the density causes heat penetration issues in the jar during processing.
The cubes of sweet potato are expected to be at least luke-warm going into the jars. (So, if you prepped them the day before and overnighted them in the fridge, you need to heat them up again somehow such as in a microwave before starting the canning process.)
If you have small sweet potatoes, you don't need to cube them; you can just quarter them.
Optional per ½ litre (US pint) jar (double for litres / US quarts): 1 tablespoon lemon or orange juice (some say can help prevent darkening; others say it just adds an interesting flavour.)
When you go to use these, drain them. Consider saving the drained water and freezing it in a tub for use in soups, etc: it makes a wonderful broth.
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)||65 mins||10 lbs||15 lb|
|1 litre (1 US quart)||90 mins||10 lbs||15 lb|
How to pressure can.
When pressure canning, you must adjust the pressure for your altitude.
More information about Salt-Free Canning in general.
Potatoes, Sweet – Pieces or Whole. United States Department of Agriculture (USDA). Complete guide to home canning. Agriculture information bulletin No. 539. 2015. Page 4-16.
Potatoes – Sweet. In: Ball Blue Book. Muncie, Indiana: Healthmark LLC / Jarden Home Brands. Edition 37. 2014. Page 115.
Sweet Potatoes. In: Kingry, Judi and Lauren Devine. Ball / Bernardin Complete Book of Home Preserving. Toronto: Robert Rose. 2015. Page 392.
Serving size: 250 g, drained (about one half of a 1/2 litre / US pint jar, if 500 g went into the jar.)
Per 250 g: 226 calories
Weight Watchers PointsPlus®: 250 g = 6 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.
To serve home canned sweet potato
Expect to serve this basically as mashed sweet potato.
Drain (tip! freeze liquid in a tub for use in a soup.) Mash with a potato masher or a fork — it’s very soft and almost no force will be required.
Mix in if desired butter, sour cream, seasonings of your choice. Zap in microwave until piping hot, 3 to 4 minutes. Serve hot.
You can also use home canned sweet potato for a sweet potato pie. Drain, mash and use as called for in the pie recipe you are following.
Use in any recipe that calls for mashed sweet potato.
Canned sweet potato is very soft
Canned sweet potato is very soft! Don’t shake the jars!
It ends up so soft that if you shake the jars, it will simply and completely dissolve within seconds in the canning water.
Immediately below is a photo of jars of sweet potato that were transported by knapsack.
There was nothing to do but use them as a base for a sweet potato soup.
Freezing sweet potato instead
If that kind of softness is unacceptable to you, consider freezing them instead. The National Center for Home Food Preservation provides the USDA’s directions for freezing sweet potato in halves, sliced or mashed.
Frozen Sweet Potato Balls
So Easy to Preserve2 gives this recipe for Frozen Sweet Potato Balls (to be clear, this is indeed for freezing only, not canning):
To prepare and freeze:
Make mashed sweet potatoes. Form into balls. Brush with melted butter or margarine. Roll in crushed cereal flakes or finely chopped nuts. Freeze balls on baking sheet before packaging in rigid containers or freezer bags. Fill air spaces with freezer paper.
Bake on greased baking sheet at 350 F (175 C ) to at least 165 F (75 C) [Ed: they mean internal temperature], about 25 to 30 minutes. They should be steaming hot before serving.
The recommended storage time for these in the freezer is up to 1 month.
Cooking with home-canned sweet potato recipes