Friday, 15 May 2009

Spherification: Why Inverse?

Oh, you lot ask some good questions. Aren’t you a bright bunch?

In response to last week’s post about mozzarella spheres, I received literally two (possibly three if you include Twitter) requests for explanations regarding the ‘inverse’ part of ‘inverse spherification’.

So, how does this differ from regular (!) spherification?

The original method Adria used for creating these suspended ravilo (singular for ravoli, apparently) was first developed back in 2003 and kept hush-hush secret for quite some time.

He discovered that salts and alginates reacted to each other and created colourless, flavourless ‘skins’ capable of holding flavoured liquids within them.

The alginate would be dissolved into the liquid to be sphere-ized and then dropped into a calcium carbonate solution where the two would react thus creating the famous orbs.

For example, alginates would be added to a puree of peas, spoonfuls of which would be dropped into a calic bath.

But there was a problem.

Even when rinsed clean in fresh water, the reaction continued.

Over a period of five minutes the sphere solidified and the diner was left with a rather disappointing ‘jelly’ as opposed to a satisfying ‘pop’ as the skin burst and filled the mouth with essence of pea, mango or mozzarella cheese.

How to get round this?

Well, simply switch the two elements. Inverse them.

Instead of adding the alginates (derived from seaweeds, much like agar agar) to the desired flavour, Adria developed an algin solution which would react with the calcium salts inside the foodstuff.

The reaction produced an almost identical outcome with the benefit of being able to halt it by rinsing the spheres in plain water. No more disappointing jellies.

Instead the result was a more stable sphere whose inside remained liquid for much longer and inverse spherification was born.

1 comment:

Hopie said...

Wow, very informative! Thank you. I feel like I'm back in high-school chemistry, (which is not a bad thing; chem was my favorite science class despite being bad at math...)