Tweaking the chocolate of the future

Whether in the form of a bar, praline or candy, many people find chocolate irresistible. Unfortunately, in addition to the ground cocoa beans, chocolate also contains a lot of fat and refined sugar - which is not good for you. Cocoa production is also far from sustainable: only the fermented, roasted cocoa beans are used. The rest of the cocoa fruit, including the flesh (pulp) and the shell, is rarely used. Some of it is used as fertiliser, but the rest is usually burned.

But there is another way, as researchers led by Kim Mishra of ETH Zurich, in collaboration with the company Koa, have now shown. They have developed a chocolate that contains cocoa beans as well as parts of the fruit pulp and skin. The advantage of this is that because the pulp is very sweet, some of the granulated sugar normally added to chocolate can be omitted. What's more, this new cocoa-fruit chocolate contains more healthy fibre.

Since 2017, the Zurich-Ghanaian company has been working on new products from cocoa cultivation. Their aim is to improve the situation of farmers in Ghana, use all parts of the cocoa fruit, and retain more of the processing steps in the country of origin. From 2017 to 2023, Koa was able to save 800 tonnes of pulp, which the industry would previously have discarded. So far, Koa has used this pulp to produce cocoa fruit juices as well as concentrates for the production of bakery products and flakes, which are also used in gastronomy and confectionery.

Thanks to the collaboration with researchers at ETH Zurich, it is now possible to use the shell of the cocoa fruit. First, the pulp is pressed to extract the cocoa juice, which is then distilled into a concentrate. This is then mixed with the remaining pulp and dried shell pieces to form a gel. By using this cocoa jelly as a substitute for granulated sugar, the sugar content found in conventional chocolate can be reduced; the nutritional value of the new cocoa-fruit chocolate is also an improvement. According to the researchers, the cocoa-fruit chocolate not only contains a third less sugar than the average dark chocolate sold in Europe, but also a third less saturated fat.

However, in order to produce the more sustainable cocoa-fruit chocolate on a larger scale, cocoa farmers must first install drying equipment to produce the powder for the gel. Then companies will be able to use the new process, which has already been patented by ETH Zurich. And not to worry: the results of the taste-test show that the new cocoa-fruit chocolate is comparable to other dark chocolates in terms of palatability and sensory perception.