Process 10: Refinig!

Hello my fellow chocolate lovers,

I am Takanori Chiwata, the chocolate engineer of COCONAMA CHOCOLATE.

Today, we will be talking about “refining.”

Are you familiar with the term “refining”?

Refining means to refine the particles of a chocolate.
What exactly are particles of a chocolate though?

Chocolates are liquefied in a warm place and solidified in a cold place, right?
This is due to the property of cacao butter, the oil produced from a cacao beans.

55% of cacao bean are its fat. This is as much oil as almonds and other nuts.
When you grind cacao beans it releases its oil, the cacao butter, it first becomes pasty and then to a liquid. A little similar to a peanut butter. The cacao is able to become a liquid form of chocolate by being grind.

General dark chocolates consists of sugar and cacao beans, and milk chocolates consists of powdered milk on top of those. Chocolates are basically sugar and other non-cacao butter cacao elements suspended in a cacao butter.

The important point here is that they are merely mixed with each other and are not dissolved with one another.
The sugar will dissolve in water, but will not in oil.
To be precise, chocolates are mixture of fat and sugar.
If you look at a chocolate under a microscope, this is the kind of image you will see.

As you can see, non-cacao butter ingredients are scattered inside the cacao butter.

What will an non-grinded ingredients　(such as sugar)taste like? They do not taste good at all with its sandy texture.
So, we will need to grind the sugar inside a cacao butter finely.

The maximum size of a particle a human tongue can sense is up until 18 μm.
1 μm is 1/1000 of 1 mm. We will need to grind the contents down to this size.
It depends on the company, but the sugar inside a general chocolate bars are grinded down to 15-20 μm.

Now, how do we grind the sugars down?

Broadly speaking, there are 4 ways to do this.

Roll refiner
Ball mill
Melanger
Refiner conche

Roll refiner is used at a large chocolate manufacturer. It is quite large in size, some of this machine may even contain a roll with a width of 2.5m. This machine is very productive and can grind large amount of sugar in a short time. However, it is unbelievably expensive. Large machine could cost anywhere from $400,000-$500,000. Not something we can have in our store, but this is what it looks like.

The black thing you see on the top is the chocolate. It first goes through roll 1 and 2, and it gets finer as it goes through rest of the rolls.
The chocolate after going through

the last roll will look something like this.

A chocolate will change its form from a paste to a powder after running through the machine. We call these flakes. It tastes pretty good with its fluffy texture.

In a ball mill, there are numbers of balls in a cylinder shaped vessel. In this machine, you put the chocolate paste in this vessel,and stir them along with the balls inside it. The sugars will then be grinded by the collision of these balls. The trouble of this machine is that it produces a lot of oil and it can only grind loose chocolates. On top of that, it is loud and it is also a trouble to clean. This machine is also decently expensive, costing about $30,000. The machine looks like the image below.

Melanger is the most traditional machine. This machine rolls a stone roll on top of a stone plate, allowing the sugars between the two to grind. The machine looks like this. You can buy a small one of this machine for about $1000. You can purchase this at a less expense, so in the recent years,we see many new bean-to-bar chocolate maker joining the industry. It is easy to clean, but the trouble of this machine is that it cannot grind all the sugars down and the ability to grind is not as strong as the 2 machines above.

In the recent years, some products are purposely coarsely grinded to leave particles, allowing a strong cacao fragrance to flow once you bite into it.

With refiner conche,you place corrugated iron sheets inside a cylinder shaped machine,and grind the chocolate particles by spinning number of corrugated sheets from the centre. The benefit of this machine is that you can place it in rather small place, but it is incredibly loud. It is not surprising,as this machines uses centrifugal force to collide numbers of steel sheets with other steel sheets. This machine will still be loud even if you place a soundproof cover over it, and place it in a soundproof room. The inside of this machine is shown as below.

Let’s call it a day now that I had the chance to share about the secret behind the smoothness of chocolate.

Next time, I would like to post about “conching chocolate”. Don’t miss it!

With hopes that you will be able to encounter the perfect chocolate just for you,

Takanori Chiwata