Commercial chocolate-making involves three further steps beyond a simple mixing of ingredients: refining, conching and tempering. Since my previous post, I've been learning about the first of these.
'Refining' chocolate involves grinding the particles in the chocolate (including the fat globules) till they are so small that your tongue can't detect them. Commercially, this is done using either roll refiners (forcing the chocolate up a series of stacked rollers not unlike the rollers in an old-fashioned wringer washing machine) or a ball mill.
On a domestic scale, the 'state of the art' solution is the Spectra 11 Melanger. Investing in such an expensive piece of equipment seemed insane for my purposes, but it gave me a clue. The Spectra 11 is a modified Indian wet grinder. We already have an Indian wet grinder: a Sumeet. It uses completely different technology, but is designed to do the same thing, so I thought I'd give it a go :-)
With a commercial refiner (or the Spectra 11), you typically leave the grinder to run for many hours - sometimes even days. I didn't know how long I could leave the Sumeet running before it overheated but I knew that it had a reliable cut-out switch so I wasn't too worried. I planted it in the sink (so it couldn't 'walk' anywhere), turned the tap away for safety, turned it on and quickly removed myself from the scene. It's very loud!
After 30 minutes I noticed a slight change in the smell, even from two rooms away, so I quickly turned it off. The chocolate appeared to have caramelised ever-so-slightly, but it was also much, much smoother. Very promising :-) I later ground it for two increments of 10 minutes, allowing it to cool significantly in between. It was yet more smooth after this, but not by much. In the future I intend to grind it in 10 minute increments and keep going until I decide it's good enough (or that I've had enough of the noise).
It seems that this grinder is much more vigorous than those normally used for chocolate. This means it has more potential to burn the chocolate, but it seems it also means that it gets the job done much more quickly.
So, here's my recipe for 'refined' white chocolate.
80g cocoa butter
80g milk powder
1/3 cup (80g) white sugar
seeds of 2/3 a vanilla bean (can probably use 1 1/3 tsp vanilla essence if you will later be adding liquid to the chocolate, e.g. if making ganache or mousse).
Mixing and refining:
1. Chop cocoa butter and melt in the microwave - takes 3-5 minutes.
2. Place Sumeet in the kitchen sink. Fit one of the large jars with square blade.
3. Grind milk powder at least 20 seconds in Sumeet spice jar then transfer to large jar.
4. Grind sugar at least 20 seconds in Sumeet spice jar then transfer to large jar.
5. Pour cocoa butter into large jar. Add vanilla.
6. Run on '1' for 10 minutes.
7. Leave to rest until close to room temperature again (approx 30 min.)
8. Run a further 10 minutes then rest again. Continue until the chocolate is as smooth as you like it. If you need to leave it for more than 30 minutes between grindings, transfer it to a shallow dish to cool. When you return, break it into pieces, melt it in the microwave and continue.
- Running the Sumeet on 1 draws around 500W, so every 10 min. uses 0.083kWhr. That's much less energy than it takes to boil the jug for a cup of tea and only costs us just over 2c. It was making so much noise I figured it must be using heaps of electricity but it's not.
- If you don't have access to a good grinder, use icing sugar for the sugar and full fat milk powder for the milk powder (both are 'softer'). Add the other ingredients to the cocoa butter very slowly, beating well as you go. You will make a product that tastes good but it will have a somewhat gritty/dusty texture.
- Other gadgets you can use to refine your chocolate are:
- other Indian wet grinders or mixers (another well-regarded brand that seems more widely available these days is Preethi, and I know people have had good success with the Premier Wonder Grinder);
- rock tumblers (e.g. Lortone Model 3A Tumbler). Use with ceramic tumbling media.
Next I need to learn to 'conch' the chocolate. In milk and dark chocolate, this step eliminates some of the bitter flavours in the chocolate. However, it's also the point at which you add an emulsifier, so it's still important for white chocolate. Emulsifying the chocolate further improves the texture and also makes it easier to temper.
I'll be using soy lecithin, the emulsifier most commonly used in chocolate. It comes in both powder and liquid forms. I've decided to use liquid lecithin as I think that will mix in better, and I've decided to buy it in capsules (rather than as a bottle of oil) as I think that will probably keep better. I'll initially add 1% soy lecithin (which means my one bottle of capsules would do 50 batches!) and generally follow this advice.