With the intro out of the way, we can crack on. Let’s begin with air. Or maybe foam. Anyone know when an air becomes a foam? Answers below please.
For the uninitiated, and those without access to liquid nitrogen, vacuum packaging devices, Large Hydron Colliders and other assorted machinery, airs and foams seem to be an excellent point of entry into the seemingly murky (and achingly complex) world of molecular gastronomy.
They are also relatively easy to create and apparently hard to fuck up (although, as expected, I did manage. You shan’t be seeing my ‘poached egg with paprika foam and roasted chickpeas’ because it looked like something from low budget Korean horror movie, circa 1983).
Airs and foams have come in for a bit of stick recently with some chefs apparently desperate to adorn all their dishes with a garnish that looks like gargled frog spawn. This is a bad thing.
But they do have their uses. They are light, delicate and carry flavours in a completely unexpected way. They’re also tremendous fun.
If you think you’ve never experienced such a level of gastronomy, think again. Unless, of course, you’ve never had a cappuccino – foam at its most famous. Or Foamous. *Sigh*
Using milk is one way to create the effect. Another is to use a chemical derived from soya beans or egg yolks called lecithin.
Although predominantly used in food production as an emulsifier (a go-between that helps the combining of fats and water – as in a béarnaise sauce), lecithin can also be added to virtually any liquid then whizzed up to create delicate bubbles of flavour.
Not wanting to ruin another perfectly good egg (see above), I thought about other possibilities and came round to the idea of using an air to flavour homemade crisps – something I first encountered at Midsummer House in Cambridge where we had crisps with a sweet balsamic foam as a pre-lunch nibble.
It was a neat twist on olive oil and balsamic vinegar, so often a satisfying starter when served with crusty bread. Time to get experimental.
With this in mind, instead of deep-frying the thin slices of potato, they were brushed on both sides with extra virgin olive oil and put into a hot oven.
Meanwhile, I mixed 75g of balsamic vinegar (not the good stuff) with the same amount of water, added 0.5g of lecithin and let it dissolve into the liquid.
Using a ‘wide mouthed container’, as recommended by another blogger, I then applied a hand blender to the surface of the liquid in an effort to create the small, stable, bubbles that form the ‘air.’
There are still dots of balsamic vinegar on the ceiling, the fridge, the kettle and, probably, my hair.
Panicking, I plunged the blender deeper into the dark liquid.
The blade managed to cut cleanly through a small raised nipple in the base of the plastic tub and all I could do was watch as foamy (hooray!) vinegar and water slowly leached out onto the surface and down onto my socks.
Sometimes all you can do is watch as the horror unfolds. So that’s what I did.
Two towels later I remembered the potatoes, now a slightly darker shade of brown than I’d anticipated.
Oops thrice. Time for coffee.
Composure and cool regained I forgot everything that had gone before and started again.
Peel potato. Slice thinly on mandolin (carefully avoiding the cutting off of fingertips). Brush lightly with EVOO and bake in a slightly cooler oven for about four minutes on either side. Salt with Malden sea salt on emergence and leave to cool on something slightly absorbent. Like David Guest’s face. Or some kitchen paper. I tend to use the latter.
Meanwhile: mix vinegar and water with weird yellow powder and blitz carefully with a hand mixer. Leave for five minutes then collect the resultant bubbles into a small receptacle. A shot glass or small espresso cup will suffice.
Dip each crisp into the foam and then shove it into your expectant mouth. Prepare yourself for a flavour explosion and a melding of textures so wondrous you’ll want to streak naked through the streets. Or at least have another. And then keep going until they are all gone.
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