Preparing celeriac is mostly a matter of washing away soil, removing its tough, knobbly skin, and cutting the firm flesh into pieces suited to your recipe. Also called celery root, celeriac has a mild, earthy flavour with a hint of celery. You can eat it raw or cook it in soups, mash, roasts, and other dishes. Have a sturdy cutting board and a sharp knife ready; because the root is uneven, careful trimming is more useful than trying to peel it like a smooth potato.
What You’ll Need
- A whole celeriac root, firm to the touch and without soft, wet or mouldy patches.
- A sharp chef’s knife and a stable cutting board. A small paring knife is useful for removing stubborn spots.
- A vegetable brush or clean scrub brush for loosening soil, plus cold running water.
- A bowl of cold water with a squeeze of lemon juice, if you want to hold cut pieces before cooking and limit browning.
- A clean kitchen towel or paper towels for drying.
A vegetable peeler is optional. The rough surface and deep creases make a knife easier to control on most roots. If you use a peeler, first trim the root into stable, flat-sided pieces.
Step-by-Step
- Choose and inspect the root. Pick celeriac that feels firm and heavy for its size. Small roots may be easier to handle, but size alone does not determine quality. Avoid roots with extensive soft areas, leaking liquid, or visible mould. A few rough roots or small rootlets are normal and can be cut away. If the celeriac has green stems or leaves, they can be trimmed off before washing.
- Rinse and scrub it. Hold the root under cool running water and scrub the whole surface with a vegetable brush. Pay attention to grooves and the areas around rootlets, where soil can cling. Do not soak it for a long time; a thorough rinse and scrub is enough. Pat it dry so it is less slippery when you cut it.
- Trim the top and base. Set the celeriac on the cutting board. With a sharp knife, slice off the leafy top and the bottom root end, removing enough to create two flat surfaces. These flat ends help the root sit securely while you work. If either end is especially dirty or damaged, cut away the affected portion rather than trying to clean soil from a deep crevice.
- Make it stable before peeling. Stand the root on one of the flat ends. If it is too large or wobbly to control comfortably, cut it in half from top to bottom and place each half flat-side down. Keep your fingers clear of the blade and use a board that does not slide. A damp towel under the board can help keep it in place, provided the towel does not bunch up.
- Remove the skin with a knife. Starting at the top, cut downward in strips, following the curve of the root and taking off the brown, rough outer layer. Cut deeply enough to remove the skin and any fibrous or discoloured flesh just beneath it, but avoid wasting large amounts of the firm, pale interior. Rotate the celeriac as you work. Use a paring knife to remove small rootlets, dirt-filled creases, or isolated blemishes. Take your time; forcing the blade through a tight spot is less safe than repositioning the piece.
- Check the peeled surface. Look over the whole root and trim any remaining brown skin, tough fibres, or dark blemishes. The flesh should look pale and feel firm. A few small tan marks can be cut out locally if the surrounding flesh is sound. If you find widespread softness, an unpleasant smell, or mould extending into the flesh, discard the root rather than attempting to salvage it.
- Cut it to suit the recipe. For mash or soup, cut the peeled root into roughly even chunks so they cook at a similar pace. For roasting, cut it into evenly sized cubes or wedges. For sticks, first slice it into slabs, then stack or lay the slabs flat and cut them into batons. For a salad or slaw, use a sharp knife to make thin matchsticks, or grate it. Keep pieces similar in thickness when they are meant to cook together; uneven cuts can leave small pieces soft before larger ones are tender.
- Use it promptly or prevent browning. Celeriac flesh can darken after cutting as it is exposed to air. This is a cosmetic change, not by itself a sign that the vegetable has spoiled. If you are not cooking it right away, put the pieces in a bowl of cold water with a little lemon juice, then drain and dry them before cooking. Alternatively, cover them and refrigerate for a short period. For the best texture, prepare it close to the time you plan to use it.
- Cook according to the dish. Add the pieces to your recipe, allowing enough time for them to become tender. For boiling or steaming, check a piece with the tip of a knife; it should be easily pierced when ready for mashing or blending. Roast evenly cut pieces in a single layer, turning as needed for more even browning. If eating it raw, slice or grate it thinly so its crisp texture is pleasant and easy to combine with dressing or other ingredients.
Common Mistakes
Trying to peel the whole root while it rolls around: The irregular shape makes this awkward and increases the chance of the knife slipping. Trim a flat base first, then halve the root if needed so it rests securely.
Removing only the outermost brown layer: Some celeriac has tough, fibrous material immediately beneath the skin. Trim until you reach clean, firm flesh, especially around the rootlets and deep grooves.
Cutting pieces in very different sizes: Uneven pieces cook at different rates. Before boiling, roasting, or steaming, take a moment to make the pieces roughly uniform for the result you want.
Leaving peeled celeriac exposed for a long time: The surface may darken. This does not automatically make it unsafe, but it can look less appealing. Use it soon or hold cut pieces in acidulated water and refrigerate them.
Using a dull knife or a slippery board: A blunt blade can require more force, while a wet root is harder to grip. Dry the celeriac, steady the board, and use a sharp knife with controlled cuts.
Tips
- Save the thick peel and trimmed ends for compost, or discard them. They are usually too tough and gritty to use as pieces in a finished dish.
- When making soup, cut the celeriac into similar-sized chunks, but precision is less important than for roasting because the pieces will be blended or mashed.
- For a smooth mash, cut the root into evenly sized pieces and cook until completely tender before draining and mashing. Drain thoroughly so excess water does not make the mash loose.
- For raw preparations, peel generously and cut just before serving. A little lemon juice in a dressing can help keep the cut surface looking pale.
- If the root is very large, work with one half at a time and keep the unused peeled portion covered in the refrigerator while you finish the first part.
- Wash your hands, knife, board, and any brush after removing soil, especially before using the board for ready-to-eat ingredients.
Troubleshooting
The root keeps wobbling. Stop cutting and trim a larger flat surface on the base. If the whole root is still awkward, halve it and place the cut side down. Do not try to hold a rounded piece in your palm while slicing.
There is soil deep in a crease. Rinse and scrub again, then cut out the crease with a paring knife. If the soil is trapped under a rootlet or inside a damaged section, remove that section rather than leaving grit behind.
The peeled flesh is turning brown. Work quickly, or place the pieces in cold water with lemon juice and refrigerate them until needed. Drain and dry them before roasting, since wet surfaces can interfere with browning. If the flesh is otherwise firm and smells normal, colour change alone is not a reason to discard it.
The pieces are browning but the recipe is not ready. Cover them and refrigerate rather than leaving them at room temperature for an extended time. For best results, cut celeriac shortly before cooking and follow the recipe’s directions for holding prepared ingredients.
The celeriac is taking longer to cook than expected. Piece size and the root itself affect cooking time. Test the thickest piece with a knife or fork, and continue cooking until it reaches the tenderness needed for your dish. If smaller pieces are already soft, remove them and let the larger ones finish.
The cooked pieces are watery or the mash is loose. Drain them well after boiling, then return them briefly to the warm, empty pot so some surface moisture can evaporate. Mash afterward and add any liquid gradually rather than all at once.
Frequently Asked Questions
Do I have to peel celeriac?
Yes, for most preparations. Its outer layer is rough and fibrous, so remove the skin and any tough material beneath it. Scrubbing alone will not make the peel pleasant to eat.
Can I eat celeriac raw?
Yes. Peel it, then slice, grate, or cut it into thin matchsticks for salads and slaws. Thin pieces are easier to eat than large raw chunks, and lemon juice or a dressed salad can complement its earthy flavour.
How do I stop cut celeriac from turning brown?
Limit its exposure to air. Put cut pieces in cold water with a little lemon juice and refrigerate them until you are ready to cook, or prepare them shortly before use. Drain and dry them before roasting.
Can I prepare celeriac in advance?
You can wash, peel, and cut it ahead, but the cut surface may discolour. Keep the pieces covered in the refrigerator, preferably submerged in acidulated water if they will be held for a while, and use them as soon as practical. Avoid leaving prepared vegetables out at room temperature for long periods.
How can I tell whether celeriac has gone bad?
Do not use it if it is extensively soft, slimy, mouldy, leaking, or has an unpleasant smell. A little surface browning after cutting is different from spoilage; judge the root by its firmness, smell, and visible condition as well.
Can I use a vegetable peeler instead of a knife?
Sometimes, particularly after trimming and cutting the root into stable slabs. However, a peeler may miss skin in deep grooves and can be difficult to control on a rounded, knobbly root. Use a small knife to finish those areas, and keep the pieces steady on the board.