[prev] [thread] [next] [lurker] [Date index for 2004/2/26]
ABSTRACT Liquid Nitrogen makes great ice cream - try it at home! INTRODUCTION So on Tuesday we had our pancake party, getting through 12+ pints of batter and assorted condiments. However, the highlight of the evening was making Liquid Nitrogen (LN2) ice cream. I'd heard that LN2 made for beautifully smooth ice cream, due to it freezing so quickly that the ice crystals formed were teeny, but had never tried it. Luckily, one of my flatmates is a PhD chemist, and so was able to bring a dewar of LN2 home with him for the evening. I don't know where you might get LN2 if you don't have this kind of access - sorry. I'd hope that anyone on this list would have an idea of the safety precautions needed - LN2 isn't very dangerous, but common sense is always useful :) EQUIPMENT AND METHODS 1 dewar LN2 (~10 litres) 1 egg yolk, lightly beaten ~150 ml double cream ~25g caster sugar flavouring (I used a dash of vanilla extract for the first batch, maple syrup for the second.) Scaled up as necessary. Mix up in a metal receptacle (small saucepan in our case), and add LN2 a small amount at a time, stirring with a wooden spoon. You won't be able to see the mixture due to the gas boil-off, but you can feel the mixture stiffen significantly as it finally freezes. Let the gas boil off and inspect. If it is still too liquid add a little more LN2. Eat immediately - this will melt quicker than normal ice cream, again due to the small crystal size. CONCLUSIONS AND FURTHER RESEARCH This was some of the best ice cream I've ever had - smooth and delicious. There was more than enough for the ~15 people there in the two batches made up, as it was very rich. Some of the recipies I've seen suggested using some milk to thin out the cream - this would mean you could have more than a few teaspoons at a time. I don't know how this would affect the freezing - I suspect more LN2 would be needed, due to the higher specific heat - see below. At the end of the evening we still had half the dewar left. We also had a fair bit of the strawberry sauce we'd made up lying around (strawberries whizzed in the blender with sugar to taste and a dash of balsamic vinegar). Someone (thanks, Flick!) suggested we could make up a nice sorbet with this and the cheap nasty Cava we had lying around. We mixed up the cava and strawberry sauce about 50/50, dumped it in the saucepan, and heaved on the LN2. This needed a lot more LN2 to freeze properly, we suspect due to the alcohol and the higher water content, but was equally great - a smooth sorbet that melted on the tongue, with the cheap cava transmuted into something wonderful - a clean, fresh taste.. This would make a great summer dessert, aperitif, or even a palate cleanser between courses. In summary, a great party trick, and one that makes damn tasty ice cream. Befriend a chemist today... -Jakob
Generated at 23:05 on 03 Mar 2004 by mariachi 0.41