Making The Cut: Testing Cacao Beans’ Health and Fermentation

Problem spotting

After cutting the beans, the first thing the cacao farmers want to know is if there are any problems in the cacao batch, like infestations, moulds, germination, slaty beans or other defects. Obviously, such batches don’t make it to the fine flavour cacao market. And it is best to detect the problem as soon as possible, so you can separate and isolate the “problem batch” making sure that this is not being mixed with a fine flavour cacao batch.  So, let’s get rid of the bad batch and use the fermentation box for a new and good one.

Level of fermentation

In the field cut tests are an essential tool to check the status of fermentation. During the process farmers regularly take out a few beans, bisect these, and evaluate the two halves. Colour is an indicator; the beans change from white or reddish/purple to brownish during fermentation. Another indicator is the veins pattern: a more veiny body implies the beans have fermented longer. Checking these indicators along with temperature and ph measurements and fermentation time, will give the farmers a signal when to stop fermentation.

Industrial approach to cutting tests

Cacao purchaser for bulk industry and specialty cacao purchasers use cut tests in very different ways. The bulk cacao industry focuses on standardized fermentation level of cacao beans. Cacao buyers of industrial chocolate makers take out their ‘shade book’ to check the colour of the cacao beans and are satisfied if there is a match. There is a tendency to aim for well-fermented cacao, high in chocolaty notes, generally a bit bitter, and preferable always the same profile.

Specialty cacao

At Silva we believe there is basically no right and wrong in fermentation – our aim is to bring out the best of it’s potential of each cacao quality by fine-tuning the selection of cacao and post-harvest protocols. In some cases interesting results are achieved with higher levels of fermentation, in other cases a slight under-fermentation might give a more interesting flavour profile. It all depends on which flavours you want to achieve.

A cut test gives us an indication of the flavour we might expect when we are testing the flavours of the raw beans to determine the organoleptic profile of the cacao. The proof is of course always in the eating – in this case of the raw or roasted beans: a flavour profile can only be determined by tasting, tasting and more tasting.

DIY Cut Test

Enough about the cut test in the field. How can you do it in your chocolate atelier/workshop/factory? 

Here is a super simple four-step process:

  1. Take 50 cacao beans and slice these lengthwise in two.
  2. Put the half beans in a row, cut size up.
  3. Examine the color and the pattern of veins, and understand the fermentation
  4. Classify them in categories according to the color & appearance

 

Interpreting the Test

A brownish color and lots of veins in the bean’s body suggest a high level of fermentation, while a purple or reddish color and a more solid body indicate a lower level of fermentation. Both are OK, there is no right or wrong here. The color and veins pattern can give you a clue about the flavor profile of the beans. Higher fermentation results – generally speaking – in more chocolaty, sweet, earthy notes, while less fermented beans can give room for more subtle flavors like fruity and floral.

If you taste your liquor or chocolate made from the beans and you verify the fermentation levels, you will understand the interlinkage between both.