Italian Celeriac, Apple and Hazelnut Vellutata | Vellutata di Sedano Rapa, Mela e Nocciole
Celeriac is the least photogenic vegetable in the Italian winter market and one of the most useful. Under that knotted skin sits dense ivory flesh tasting of celery, parsley root and something faintly nutty, and cooked soft then blended hard it becomes a soup with the body of cream and not a spoonful of cream in it.
A tart apple sharpens the root, toasted hazelnuts supply the fat that makes the texture, and the whole plate comes together inside an hour.
Yield: 4 first course servings. Prep: 20 minutes. Cook: 30 minutes. Total: about 50 minutes. Difficulty: easy to intermediate. Course: primo piatto. Region: Piedmont and the northern Italian winter table.
The Story
Sedano rapa arrived in Italy from central Europe and settled in the north, where the cold sits long enough for the root to swell and sweeten. It grows on the Veneto plain, across Friuli, in the Emilian countryside around Bologna and up into the valleys of Trentino, and for most of its Italian life it was food for households that could not afford much else. It stores for months in a cellar without losing its character, it asks very little of the soil, and it reaches the market at exactly the moment tomatoes, courgettes and basil have gone. Cookbooks from the 1930s treat it as a filler for broth or as a raw winter salad, grated and dressed with vinegar. Restaurants ignored it almost entirely until the 1990s, when the fashion for forgotten vegetables finally reached the root cellar.
The vellutata is the frame that rescued it. In Italian kitchen language a vellutata is not the same thing as a passato or a crema: a passato is simply a vegetable pushed through a mill, a crema is bound with dairy, and a vellutata is defined by the mouthfeel it delivers, velvety, coating and uniform, however that mouthfeel gets there. The traditional binder was never a roux and rarely panna. It was a starchy vegetable, usually a handful of potato, cooked into the soup and then blended into it. Trattorie across Piedmont and Lombardy were turning out vellutate of leek, pumpkin and cardoon long before anyone thought the method needed a name, and it is exactly the instinct modern cooking came back to a century later.
The other two ingredients come from the same geography. The hazelnut of the Langhe, the Tonda Gentile that carries the Nocciola Piemonte IGP, is the most fragrant in Europe and the one Piedmontese cooks reach for the way Ligurians reach for pine nuts. Apples come down from Alto Adige and the Val di Non by the truckload all winter. Put the three on one table and the logic writes itself: the root is earthy and slightly bitter, the apple is acidic and aromatic, the hazelnut is rich and toasted. Each one covers what the other two lack, and none of them needs to be in season anywhere but here.
Ingredients
For the vellutata
Celeriac, peeled and cut into 3/4 inch (2 cm) cubes, 1 3/4 lb (800 g) after peeling
Yellow fleshed potato, a waxy variety, peeled and diced, 5 oz (140 g)
Leek, white part only, washed and thinly sliced, 1 medium
Tart apple such as Granny Smith or Renetta, peeled, cored and diced, 7 oz (200 g)
Unsalted butter, 2 tbsp (28 g)
Extra virgin olive oil, mild and not peppery, 1 tbsp (15 ml)
Dry white wine, 1/4 cup (60 ml)
Light vegetable stock, kept hot, 4 cups (950 ml)
Fine sea salt, 1 1/2 tsp (9 g), plus a pinch for the leek
Freshly ground white pepper, to taste
Freshly grated nutmeg, 1 small pinch
Fresh lemon juice, 1 tsp (5 ml), to correct the finished soup
For the acidulated water
Cold water, 6 cups (1.4 L)
Fresh lemon juice, 3 tbsp (45 ml)
For the hazelnuts
Shelled hazelnuts, skin on, preferably Tonda Gentile delle Langhe, 4 oz (115 g)
Fine sea salt, 1 small pinch
For finishing
Apple, unpeeled, cut into fine matchsticks at the last moment, 1/2
Fresh lemon juice, 1 tsp (5 ml), for the apple matchsticks
Hazelnut oil, cold pressed, 2 tsp (10 ml)
Extra virgin olive oil, a few drops per bowl
Pale celery leaves from the heart, small, 12
Flaky sea salt, to taste
Freshly ground white pepper, to taste
Preparation
Step 1
Set the acidulated water before you touch a knife. Combine the cold water and the 3 tablespoons of lemon juice in a large bowl and put it beside the board. Peel the celeriac generously with a knife rather than a peeler, since the outer layer is fibrous and woody, then cut the flesh into cubes of about 3/4 inch (2 cm) and drop them into the acidulated water as you go, not in one batch at the end. Peel and dice the apple into the same bowl. Both surfaces begin to brown within two or three minutes of meeting air, and once brown they do not come back.
Step 2
Toast and skin the hazelnuts. Heat the oven to 325°F (165°C), spread the nuts on a small tray and give them 10 to 12 minutes, shaking the tray once. They are ready when the skins have cracked and the kitchen smells sweet, not when they look dark. Tip them onto a clean kitchen towel, fold it over and rub firmly for half a minute: most of the skin comes away, and the last stubborn flecks are worth leaving. Set aside a third of the nuts whole for the garnish and crush the rest roughly.
Step 3
Sweat the leek. Melt the butter with the olive oil in a heavy pot over medium low heat, add the sliced leek and a pinch of salt and cook for 6 to 8 minutes, stirring often. This is a sweat and not a fry: the leek must go completely soft and sweet with no colour at all, because even light golden edges put a roasted note into a soup meant to taste pale and clean. Pour in the wine, raise the heat and reduce until the pot is almost dry.
Step 4
Cook the root, the potato and the apple. Drain the celeriac and apple, shake them dry and add them to the pot with the diced potato, the rest of the salt and a grating of nutmeg. Stir for two minutes so everything is coated in the fat, then pour in the hot stock. It should barely cover the vegetables; sitting well above them it gives a thin soup. Simmer partly covered for 18 to 22 minutes, until a knife meets no resistance at all in the largest cube. Undercooked celeriac never blends smooth.
Step 5
Blend at full speed with the crushed hazelnuts. Add the crushed nuts to the pot, then transfer everything to a high speed blender in two batches, each no more than two thirds full, and start slow before taking it to maximum for a full 60 to 90 seconds per batch. This is where the texture is made. Long blending at high speed drives the hazelnut fat into the vegetable liquid and produces the velvet; a short blitz gives a gritty pale soup with the same ingredients and no body.
Step 6
Sieve, season and hold. Pass the soup through a fine mesh sieve into a clean pot, pressing with a ladle. Two minutes of work removes the last fibres of celeriac and hazelnut skin, and it is the difference between home cooking and a plated vellutata. Correct the salt, add white pepper and, if the apple has faded, the lemon juice. Hold it covered at about 150°F (65°C) without letting it boil again.
Plating
Warm the bowls properly, which here means hot. A vellutata is a thin layer of hot liquid spread across a wide cold surface and it loses heat faster than almost anything else leaving a kitchen. Use wide shallow bowls with a flat base, warmed a few minutes in a low oven, and take them out as you ladle.
Ladle about 6 fl oz (180 ml) into each and let it settle flat by itself, so the surface stays smooth and matte. Set the whole hazelnuts slightly off centre in a loose group, scatter the apple matchsticks beside them, tuck in two or three celery leaves, then finish with a thread of hazelnut oil, a few drops of olive oil, flaky salt and one turn of white pepper. No cream swirl, no crouton: the bowl is one colour on purpose.
Professional Technique
Two technical decisions make this dish, and both run against the reflex of a home cook. The first is the control of enzymatic browning. Celeriac and apple both carry high levels of polyphenol oxidase, the enzyme that turns a cut surface brown as soon as oxygen reaches it, and in both cases the reaction starts within two or three minutes and is fully visible inside ten. It is not spoilage and it does no harm, but it takes the soup from ivory to the colour of weak tea, and nothing done later pulls that colour back. This is why the acidulated water is set up before the knife is picked up rather than after. Lemon juice works on two fronts at once: it drops the pH below the range where the enzyme is efficient, and the water itself keeps oxygen off the cut faces. The alternative is to work fast enough that every piece reaches the hot pot within minutes, which is possible but leaves no margin at all.
The second is vellutatura without cream. The velvet is a genuine emulsion rather than a dairy addition: 4 oz (115 g) of hazelnuts carry around 70 grams of fat, and a high speed blender run for a full 60 to 90 seconds breaks that fat into droplets fine enough to stay suspended in the starchy liquid, with potato starch and apple pectin acting as the stabilisers that hold them there. Blend for fifteen seconds and the same ingredients give a thin soup with visible grit. The power and the duration are the technique, and cream would only hide the fact that it was skipped.
Texture and Moisture Control
The consistency to aim for coats the back of a spoon and then flows off cleanly, leaving a thin even film. It should never mound and never run like broth. Stock quantity is the coarse control, blending time the fine one. Too loose, and a few minutes uncovered over low heat reduces it and concentrates the flavour at once. Too thick, which it will become as it stands because of the potato starch, and it slackens with hot stock rather than water.
Heat is the enemy of the emulsion once it exists. Boiling a blended nut soup drives the suspended fat droplets back together and the surface breaks into oily patches. Hold it covered at around 150°F (65°C), never above a bare shiver.
The garnish carries all the contrast, so protect it. Whole hazelnuts stay crisp for a minute or two in a hot bowl and then soften, which is why they go on at the pass and not in the kitchen. Apple matchsticks weep and go limp within five minutes of cutting, so cut and dress them as the bowls leave.
Professional Mise en Place
Everything except the garnish can be done ahead, and the soup is better for an hour of rest, so this is a genuinely easy dish to serve to a table.
Equipment and tools
High speed blender, the single piece of equipment that cannot be substituted
Fine mesh conical sieve and a small ladle to press with
Heavy bottomed pot of 4 quart (4 L) capacity
Large bowl for the acidulated water, set up before any cutting
Sharp paring knife for peeling the celeriac, not a vegetable peeler
Prepared ahead
Vellutata blended and sieved, up to 2 days ahead, refrigerated
Hazelnuts toasted, skinned and split into crushed and whole, same day, kept airtight
Vegetable stock made and held hot
Bowls set aside ready to warm
Service setup
Soup covered over the lowest heat at about 150°F (65°C), whisk beside the pot
Bowls warming in a low oven and taken out one by one
Apple cut to matchsticks and dressed with lemon at the last moment
Hazelnut oil, olive oil, flaky salt, celery leaves and whole nuts lined up within reach
Chef Tips
Buy the heaviest celeriac you can lift for its size and press the crown with a thumb first. A root that gives at all is hollow inside, and hollow celeriac will not blend to a velvet however long the blender runs. Expect to lose a quarter of the weight to peeling.
Use a genuinely tart apple. Granny Smith is reliable and an acidic Renetta from the Val di Non is better still. A sweet variety such as Gala turns the soup faintly sugary and removes the edge that stops the celeriac feeling heavy.
Keep a spoonful of crushed hazelnuts out of the blender and taste the soup both ways. Some celeriac is far sweeter than others, and on a sweet root the full quantity of nut tips the balance soft. Blending more in is easy; taking it out is not.
Make it the day before if you are cooking for guests. The flavour rounds out overnight and the celeriac stops tasting raw at the edges. Reheat gently and check the consistency.
Common Mistakes
Cutting the celeriac and apple before the acidulated water is ready. Both brown within minutes and the soup finishes grey brown instead of ivory. Set the lemon water out first and drop each piece in as it is cut.
Blending for fifteen seconds. The velvet comes from driving hazelnut fat into the liquid, and that takes a full 60 to 90 seconds at maximum speed per batch. A short blitz leaves a gritty soup.
Letting the leek take colour. Golden edges put a roasted, oniony note into a soup that should taste pale and clean. Stop when the leek is soft and translucent.
Drowning the vegetables in stock. It should barely cover them. Too much gives a thin soup, and reducing afterwards costs the fresh apple aroma that is already fading.
Reaching for cream to fix the texture. Cream flattens the celeriac and buries the hazelnut, and it is almost always a patch for blending cut short. Blend longer, or reduce a little, instead.
Garnishing in the kitchen. Hazelnuts soften and apple matchsticks go limp in a hot bowl within minutes. Both go on as the bowls leave the pass.
Wine Pairing
Roero Arneis DOCG: The closest bottle to the dish geographically and the most natural on the list. Arneis from the sandy Roero hills finishes on a distinctly bitter almond note that runs alongside the toasted hazelnut, and its white peach fruit answers the apple. It has enough body to sit under a soup this rich without thinning out.
Erbaluce di Caluso DOCG: Chosen for acidity above everything else. Erbaluce has some of the highest natural acidity in Piedmont and its sharp green apple and citrus attack cuts the hazelnut fat cleanly, resetting the palate between spoonfuls. Its faintly saline, mineral finish also lifts the earthiness of the root rather than adding weight to it.
Ribolla Gialla Collio DOC: A Friulian answer, chosen for texture. Ribolla has a broader, slightly waxy palate than most northern whites, with a gentle bitter grip that meets the vegetal edge of the celeriac directly. Enough substance for a blended soup, enough acidity not to sit heavy.
Valle d'Aosta Petite Arvine: The alpine choice, and the most aromatic pairing here. Grown on high terraces, it brings grapefruit, white flowers and a hard stony minerality that plays against the sweetness of the cooked root. Its cool, taut structure suits a winter first course served hot from the pass.
Trento DOC: The metodo classico option, for anyone who wants bubbles with a soup. The bead scrubs the coating hazelnut fat off the palate, the mountain acidity handles the apple, and the bready autolytic notes from the lees pick up the toasted nut.
Storage & Reheating
The vellutata keeps in an airtight container in the refrigerator for up to 3 days and improves after the first night, as the celeriac loses its raw edge. Cool it quickly before it goes in, and expect it thicker when cold because of the potato starch. It also freezes well in portions for up to 2 months, unusual for a blended soup and down to the potato and nut fat holding it together.
Reheat slowly over low heat with a whisk in hand, or in short microwave bursts with a stir between each. Never let it boil: a nut emulsion that boils breaks, and the oily patches that rise will not stir back in. Slacken it with hot stock, never water. Thaw frozen portions overnight in the refrigerator and give them 20 seconds in the blender if the texture looks broken. Toast the garnish hazelnuts fresh.
Nutrition
Per serving, based on 4 first course portions:
Calories: 410 kcal
Total Fat: 30 g
Saturated Fat: 5 g
Trans Fat: 0 g
Unsaturated Fat: 24 g
Cholesterol: 15 mg
Sodium: 620 mg
Total Carbohydrates: 31 g
Fiber: 7 g
Total Sugars: 12 g
Added Sugars: 0 g
Protein: 8 g
Lactose: 0.3 g
Principal micronutrients: vitamin E, vitamin K, potassium, phosphorus, manganese, copper, magnesium, folate
These figures are estimates and vary with the stock used.
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