Valle d'Aosta is the only region in Italy where olive oil is not produced. As you can easily guess, the climate doesn’t allow for it, since the Mediterranean Sea is too far away. But this hasn’t kept the locals of Valle d’Aosta from inventing an oil from ingredients available to them at the time (i.e. walnuts).
Walnut oil
The only oil used in Valle d’Aosta kitchens is butter! In Italy, we joke that they even use it to season their salads! Joking (and butter) aside, though, the residents of Valle d’Aosta started producing oil in the 1970s and 80s from hot-pressing walnuts. "Here in the valley, we must adapt to nature – not the other way around," says Denise Marcoz from the local farm Le Grand Baöu. The press can be communal, or homemade (with smaller dimensions), but it’s usually on the smaller side, especially considering that you’ll need about 3 kg cleaned and shelled walnut kernels to make 1 liter of oil. Fortunately, though, the Bertolin family (who are also producers of traditional Valle d’Aosta lardo di Arnad) decided to start experimenting with hot-pressing the walnuts in 2004 in an attempt to find the best production method for this local tradition. So, after various studies and experiments, today’s walnut oil production has become not only a well-established craft activity, but also the highest quality walnut oil the area has ever produced! These days, the walnuts are first selected one-by-one with great care and left to dry following the autumn harvest period. The pressing begins in January and lasts for a few weeks until the bottling starts. Once ready, walnut oil is consumed as is – ideally used to season other local specialties like mocetta. Then from the walnut oil comes a rare specialty unknown to any other region in Italy – the troillet, which is the “paste” left over from hot-pressing the walnuts.
What is troillet?
In Valle d'Aosta, hot-pressing the walnuts for their oil creates a sort of residue from the nuts, making for a dense product you won’t find anywhere else. Yep, you read that right: Troillet – also ‘troliet’ or ‘troilliet’ depending on the particular valley you’re in – is made from the leftovers of pressed walnuts. It almost looks like a hazelnut-colored dough with a grainy consistency and delicate flavor, that still somehow maintains all the flavor of the walnuts. Often considered leftovers or a by-product of the walnut pressing, some locals use it as chicken feed! But for others, the troillet is a particular delicacy in the kitchen when used to dress salads (especially salads with chicory or dandelion) or to make troillet pesto with sage, which is seriously delicious spread on a bread crostini (since pasta isn’t eaten very often in Valle d’Aosta). In the past, however, when bread wasn’t so easy to get, locals would grate it into their coffee with milk for breakfast – and the kids would steal a little extra to take to school for a snack. But who can blame them? Troillet is so delicious that it's hard to stop!
To try it yourself, we suggest a stop at Denise Marcoz’s Le Grand Baöu (which means ‘big stable’ in the local patois). This is one of the few farms where they produce troillet in-house and serve it, as an aperitif already set on the table when you’re seated (instead of the usual bread basket). Denise also uses it in desserts on her menu, combined with honey – similar to the sugar-egg white cookies or the traditional semifreddo you can find at the Dupont Pasticceria. But if you can’t make it to Italy any time soon, try making the Dupont semifreddo at home with the recipe below.
Homemade semifreddo al troillet
Serves 6
Ingredients
4 egg yolks
4 egg whites
2.4 cl juniper-infused grappa
11 oz heavy cream
2 oz troillet
1 tbls chopped wild fennel
4 oz sugar
For the vanilla cream
2 cups whole milk
5 oz superfine caster sugar
1 oz type “00” flour
4 egg yolks
1 sachet of vanilla powder
1 tbls lemon zest
Start with the semifreddo base
Beat the egg yolks with the sugar and the grappa. Finely chop the troilliet and add the wild fennel. Then mix in the beaten egg yolks. Whip the heavy cream and egg whites until stiff peaks form. Mix everything gently and pour into a mold. Transfer to the freezer for two hours.
Then make the vanilla cream and serve!
Boil the milk with half the sugar, the lemon zest and vanilla. Separately, beat the egg yolks with the remaining sugar and flour. Add the hot milk and heat until the temperature reaches 195°F (90°C). Let cool in an ice water bath. Serve the semifreddo decorated with the vanilla cream, fresh whipped cream and raspberries.