Yes, you need to peel carrots before canning them. The National Center for Home Food Preservation (NCHFP), which publishes the USDA-backed guidelines for home canning, explicitly instructs: “Wash, peel, and rewash carrots” as the standard procedure. This isn’t optional or cosmetic. Peeling serves both a safety function and a quality function that matters more in canning than in everyday cooking.
Why Peeling Is a Safety Step
Carrots grow directly in the soil, and that soil contact is the core issue. Bacterial spores, including those that produce botulism toxin, are naturally present in dirt. A French study examining 316 samples of raw carrots and green beans found that raw carrots had a significantly higher incidence of dangerous anaerobic spore-forming organisms than green beans, specifically because carrots grow underground in direct contact with soil.
The NCHFP states plainly that “peeling root crops, underground stem crops, and tomatoes reduces their numbers greatly.” No amount of scrubbing removes all the spores embedded in the skin’s crevices. Since canning creates exactly the low-oxygen, room-temperature environment where botulism spores thrive, reducing the bacterial load before sealing the jar is a critical safety measure. The approved processing times were developed and tested using peeled carrots. Using unpeeled carrots introduces a variable that hasn’t been validated as safe.
How Peeling Affects Flavor
Beyond safety, there’s a good culinary reason to peel. Research published in LWT (a food science journal) found that the compounds most responsible for bitterness in carrots, specifically falcarindiol and a certain caffeic acid derivative, are concentrated in the peel rather than distributed evenly through the root. Peeling before canning removes the bulk of these bitter compounds. Since canned carrots sit in liquid for weeks or months, any bitterness from the skin has plenty of time to leach into the surrounding liquid and intensify. The result with unpeeled carrots would be noticeably more bitter than what you’d get from peeled ones.
What About Baby Carrots?
Store-bought baby carrots are already peeled during manufacturing (they’re cut and tumbled from larger carrots), so you might assume they’re ready to go straight into jars. They still need a thorough wash and rewash before canning. MSU Extension’s canning guide for carrots specifies selecting small carrots “preferably 1 to 1¼ inches in diameter” and notes that larger carrots are often too tough for good results. If you’re using true baby carrots from the garden rather than the manufactured kind, peel them just like full-sized carrots.
The Full Preparation Process
The NCHFP-approved method for canning carrots calls for sliced or diced carrots only. No tested process exists for canning whole carrots. Here’s the step-by-step preparation:
- Wash carrots to remove visible dirt.
- Peel with a vegetable peeler or paring knife.
- Rewash after peeling to remove any residue loosened during the peeling step.
- Slice or dice to a uniform size for even heat penetration.
You can use either a hot pack or raw pack method. For raw packing, fill jars tightly with the prepared unheated carrot pieces, then add boiling water. For hot packing, bring the carrot pieces to a boil and simmer for 2 to 5 minutes before loosely filling jars with the hot carrots and cooking liquid. Both methods require adding boiling liquid to the jars before processing.
Processing Times and Pressure
Carrots are a low-acid food, so a pressure canner is the only safe option. A boiling water bath will not reach a high enough temperature to destroy botulism spores.
For a dial-gauge pressure canner at elevations below 2,000 feet, process pints for 25 minutes and quarts for 30 minutes at 11 PSI. For a weighted-gauge canner below 1,000 feet, use 10 PSI with the same time. Above 1,000 feet with a weighted-gauge canner, increase to 15 PSI. These times and pressures apply to both hot pack and raw pack methods.
If you live at higher elevations, you’ll need to increase pressure further. At 2,001 to 4,000 feet with a dial gauge, use 12 PSI. At 4,001 to 6,000 feet, use 13 PSI. At 6,001 to 8,000 feet, use 14 PSI. The processing time stays the same regardless of elevation.
Choosing the Right Carrots
Not every carrot cans well. Select young, tender carrots that are medium length and coreless (or nearly so). Older, larger carrots tend to have a woody core that becomes unpleasantly tough after pressure processing. Carrots around 1 to 1¼ inches in diameter give the best texture. If you’re working with garden carrots, can them as soon as possible after harvest for the best flavor and the lowest bacterial load on the skin.