Blueberry frozen yogurt
Purple frozen yogurt made with briefly cooked blueberries and Greek-style yogurt.
Blueberries have a firm skin that holds most of their colour and flavour. A brief simmer makes them burst and release their juice, turning the mix purple. The fruit is cooked separately and cooled completely — the yogurt never gets heated.
Type: Frozen yogurt · Servings: 8 · Difficulty: Moderate
Equipment
Ingredients
- 300 g bilberries / blueberries (fresh or frozen)
- 100 g granulated sugar (sucrose)
- 40 g dextrose (glucose powder)
- 15 g lemon juice (fresh)
- 60 g whole milk 3.5 %
- 30 g skimmed milk powder
- 1.5 g locust bean gum (carob gum, E410)
- 300 g Greek-style yogurt 10 %
- 200 g plain yogurt 3 %
Making the mix
- Simmer the blueberries with half the sugar and the lemon juice for 5 minutes until they burst. Blend with a stick blender.
- In a second small pan, mix the dry ingredients: the rest of the sugar, dextrose, milk powder and locust bean gum; stir in the milk and heat to 85 °C. Hold for two minutes.
- Combine the two mixtures, cool them in iced water, then chill completely in the fridge.
- Whisk the cold blueberry syrup with both yogurts. Don’t heat the yogurt.
- Leave the mix in the fridge for an hour.
Method — Compressor ice cream maker
- Switch on the ice cream maker 5–10 minutes in advance so the bowl pre-chills.
- Pour in the chilled mix (no higher than the fill line) and churn for 25–35 minutes until it has the consistency of a thick cream.
- You can serve it soft straight away, like soft-serve. For scoops, transfer it to a chilled container, cover with cling film and leave to harden in the freezer.
Total time: 4 h 10 min
Method — Freezer-bowl ice cream maker
- Freeze the bowl for at least 24 hours in advance. Take it out just before use, fit the paddle and switch the machine on.
- With the machine running, pour in the thoroughly chilled mix — filling the bowl no more than two-thirds full; freeze the rest as a second batch.
- Churn for 20–30 minutes until the mix thickens. Going on longer is pointless — the bowl has already warmed up.
- Transfer to a chilled container and leave to harden in the freezer for 2 hours.
Frozen yogurt has less fat than cream ice cream, so it thickens more slowly in a freezer bowl. The mix must be really cold (5 °C or below), otherwise it stays runny.
Total time: 4 h 35 min
Method — Ninja CREAMi and similar machines
- Pour the chilled mix into the CREAMi tub up to the MAX line (one or two tubs, depending on their size), put the lid on and freeze level for 24 hours.
- Put the tub in the machine and run the Frozen Yogurt (if your model doesn’t have it, Lite Ice Cream) program.
- If the result is crumbly or powdery, run Re-spin — with a very cold freezer even twice (many users add 1–2 tablespoons of milk or yogurt first).
Programme: Frozen Yogurt (if your model doesn’t have it, Lite Ice Cream)
Total time: 26 h 15 min
Stages
- Preparation
- 20 min
- Cooking
- 10 min
- Cooling
- 40 min
- Ageing in the fridge
- 1 h
- Churning
- 30 min
- Hardening in the freezer
- 1 h 30 min
- Total time
- 4 h 10 min
Serving and storage
With a handful of fresh blueberries and a little grated lemon zest. It is also excellent with an oat crumble.
In a sealed container, 4–5 days.
Tips
- For a marbled effect, set aside a third of the blueberry purée and layer it between the plain frozen yogurt as you transfer it to the container.
- Wild (bilberry-type) blueberries give a darker colour and a stronger flavour than cultivated ones.
- Cinnamon or lavender (a pinch of dried flowers simmered with the fruit) goes beautifully with blueberries.
Why it works
Blueberries naturally contain about 10 % sugars (glucose and fructose) and plenty of pectin in their skins. Cooking releases the pectin and thickens the mix slightly, so the frozen yogurt is smoother. The acid from the lemon keeps the colour purple; without it, in contact with milk, it would turn blue or even grey.