Tool
How much juice do I need to freeze for ice cider?
The mass balance behind ice cider: how much concentrate a juice can give at a target Brix, how much more acid it will carry, and where a ferment on it has to stop to sit inside the window Quebec’s rules draw — stated as the floor it is, because ice never gives up all its sugar.
Freeze concentration planner
Apple juice is normally 11–14 °Bx.
Quebec’s cider regulation requires at least 30 °Bx before fermentation; the protected name requires about 32.
Concentrate from this juice
At most 7.2 L
Concentrated by: × 2.6
This is an estimate from a model, not a measurement.
How this is worked out
- Share of the juice’s mass kept: 12.5 ÷ 32.0 = 39%
- Share of its volume: 39% × 1.050 ÷ 1.139 = 36%
- Juice per litre of concentrate, at least: 2.8 L
- Acid, phenolics and minerals concentrated by: × 2.6
- Fermentable sugar in the concentrate, about: 328 g/L
- Against Quebec’s cider regulation: Inside the window Quebec’s regulation sets: the sugar falls to the 130 g/L minimum at about 11.6% alcohol, below the 13% ceiling.
What this assumes (5)
- This is the most concentrate the juice can give. Ice traps sugary liquid and the last runnings are weak, so real recoveries are lower; plan on more juice, not less.
- Freezing concentrates everything dissolved, not only sugar. If the juice is low in acid the concentrate will taste flat however sweet it is.
- The fermentation figures assume sugar is about 90% of the dissolved solids and that about 17 g/L of sugar makes 1% alcohol. Both vary.
- The 30 °Brix, 130 g/L and 13% figures are Quebec’s regulation for the term cidre de glace, and apply in Quebec. The protected name Cidre de glace du Québec is stricter: about 32 °Brix, at least 140 g/L of residual sugar and 9–13% alcohol. Both require natural cold rather than a freezer.
- This plans juice frozen before fermentation. Freezing a fermented cider to raise its strength is a different act, and is treated differently in law.
Why the answer is a floor
The calculation assumes the ice is pure water and that every drop of concentrate is recovered. Neither happens. Ice crystals grow around pockets of sugary liquid, and as a frozen block thaws the first runnings are the richest while the last are barely sweeter than the juice. A maker who wants to reach a target has to stop collecting before the ice is spent and leave that sugar behind, so the juice needed is always more than this says.
What the arithmetic does get right is everything else that rises with the sugar. The acid, the phenolics and the minerals are concentrated by the same factor, which is why ice cider is made from sharp cold-climate fruit: a low-acid juice concentrates into something merely syrupy. The ice cider page sets out the same mass balance and the window Quebec’s rules draw, and freeze concentration against cryoextraction explains why pressing frozen fruit recovers less.