Freezing gin

SIR – John Pentland (Letters, August 14) is wrong to assert that freezing a gin and tonic would produce ordinary ice mixed with liquid alcohol.

In fact, at concentrations of 10, 20 and 40 per cent by volume, the freezing point of ethanol in water is about -4C, -9C and -23C respectively, although the presence of dissolved sugar, quinine and carbon dioxide make empirical investigation essential.

My freezer, operating at about -18C, readily turns a proprietary canned gin and tonic, containing 5 per cent of alcohol by volume, into a solid crystalline mass. Cheers! John Rudkin Eversden, Cambridgeshire