Pistachio gelato

Equipment

• Compressor ice cream maker
• Freezer-bowl ice cream maker
• Ninja CREAMi and similar machines

Ingredients

• 680 g whole milk 3.5 %
• 60 g whipping cream 33 %
• 35 g skimmed milk powder
• 100 g pistachio paste 100 % (100 % pistachios, no sugar or colouring)
• 125 g granulated sugar (sucrose)
• 55 g dextrose (glucose powder)
• 2 g locust bean gum (carob gum, E410) (or 3 g of ready-made gelato stabiliser)
• 1 g guar gum (E412)
• 0.5 g salt (optional, a pinch — brings out the flavour)
• 30 g pistachios (shelled, unsalted) (for topping or folding in at the end, chopped, for sprinkling)

Making the mix

1. Mix the locust bean gum and guar gum thoroughly with the dry sugars (granulated sugar and dextrose). On their own they would form lumps as soon as they get wet.
2. Pour the milk, cream and milk powder into a pan and heat while whisking. When the mixture is lukewarm (about 40 °C), gradually add the sugars and whisk until they dissolve.
3. Heat the mix to 85 °C (check with a thermometer) and hold it at that temperature for 1–2 minutes, stirring constantly. This pasteurises the mix and fully hydrates the stabiliser.
4. Take the pan off the heat, add the pistachio paste (and a pinch of salt) and blend until smooth with a stick blender.
5. Stand the pan in a bowl of iced water and cool the mix below 5 °C as quickly as possible, stirring now and then.
6. Cover and leave the mix to age in the fridge for 4–12 hours, ideally overnight. Meanwhile the proteins and stabiliser bind water and the mix thickens.

Method — Compressor ice cream maker

1. Switch the ice cream maker on 5–10 minutes in advance so the bowl can pre-chill.
2. Give the aged mix a quick blitz with a stick blender and pour it into the bowl, no higher than the max line.
3. Churn for about 30–40 minutes, until the gelato is thick and glossy and clings to the paddle. Then switch the machine off — churning any longer would only whip in unnecessary air.
4. Transfer to a chilled tub, press cling film onto the surface and leave to harden in the freezer for 1–2 hours.

Total time: 7 h 30 min

Method — Freezer-bowl ice cream maker

1. Take the bowl, frozen for at least 24 hours, out of the freezer just before use, fit the paddle and switch the machine on.
2. With the machine running, pour in the well-chilled, freshly blended mix — filling the bowl no more than two-thirds full.
3. Churn for 20–30 minutes, until the gelato thickens to a soft-serve consistency. There is no point going longer — by then the bowl has warmed up.
4. Transfer to a chilled tub, press cling film onto the surface and leave to harden in the freezer for 2–3 hours.

A freezer bowl only partly freezes the mix, so the gelato needs longer to harden in the freezer and tends to be slightly less smooth than from a compressor machine. A well-chilled, properly aged mix helps.

Total time: 8 h 20 min

Method — Ninja CREAMi and similar machines

1. Pour the aged mix into the CREAMi tub up to the MAX line, put the lid on and freeze on a level surface for 24 hours.
2. Fit the tub into the machine and run the Gelato programme (if your model doesn’t have it, use Ice Cream).
3. If the gelato is powdery or crumbly, run Re-spin, and a second time if needed (many users add 1–2 tablespoons of milk first).
4. Serve straight away. Level off whatever is left, refreeze it and process it again before the next serving.

Programme: Gelato

The fat from the pistachios keeps the CREAMi block creamy, so there is no need to change the recipe. After spinning you can add chopped pistachios to a well in the centre and run Mix-in.

Total time: 29 h

Stages

Preparation

15 min

Cooking

10 min

Cooling

30 min

Ageing in the fridge

4 h

Churning

35 min

Hardening in the freezer

2 h

Total time

7 h 30 min

Serving and storage

Sprinkle with chopped pistachios; it is also excellent with dark chocolate or fior di latte. Gelaterias keep it in the display case at −11 to −13 °C, while a home freezer runs at −18 °C — straight out of it, gelato is hard. So move the tub to the fridge 15–20 minutes before serving (or leave it at room temperature for 8–10 minutes) and work the gelato with a spatula before scooping, just as they do in a gelateria.

Artisan gelato is made to be eaten fresh: it is best on the day you make it and within 3–5 days. In a closed tub with cling film pressed onto the surface it will keep in the freezer for up to two weeks, but it gradually hardens and ice crystals build up.

Tips

• Check the label for “100 % pistachios”. Pastes with sugar, oil or colouring throw off both the balance and the flavour.
• You can make the paste yourself: roast 200 g of shelled unsalted pistachios for 8 minutes at 150 °C, then blend in a high-speed blender for 8–12 minutes until they release their oil and turn into a runny paste.
• Sicilian pistachios from Bronte have a stronger flavour — if you can get them, the gelato will be more intense.
• You can buy locust bean gum (carob gum, E410) and guar gum in health food shops. To do without a stabiliser, stir 15–20 g of cornflour (cornstarch) into a little cold milk, whisk it into the mix and simmer for 2 minutes — that is the Sicilian way. The gelato will be slightly denser.

Why it works

Pistachio paste is around 45 % fat, so 100 g of paste adds about 4.5 % fat to the mix — which is why only a little cream is needed. Total fat comes to around 8.5 % and total solids to about 39 %. The nut solids thicken the mix without freezing, so the gelato is dense even with little overrun. Anti-freezing power (PAC) tells you how much water stays unfrozen at a given temperature — the higher it is, the softer the gelato. Dextrose has almost twice the anti-freezing power of granulated sugar but is about a third less sweet, which is why gelaterias combine the two sugars.

Sources

• Carpigiani Gelato University
• GialloZafferano: Gelato al pistacchio senza gelatiera
• Ice Cream Science (Ruben Hofmann): Stabilizers in ice cream