COMMITTED: COCA, MACHETES AND MECHANICAL ENGINEERING

Cocoa is a versatile product and is not just for chocolate: white, creamy cocoa butter is in strong demand in the cosmetics industry. Cameroonian farmers have been able to earn a lot of money with this "cash crop," meaning an agricultural product that is grown specifically for export. But unfortunately, they are unable to exploit the full potential of this product: In order to get at the precious interior of the beans, the pod is almost always cut open manually, using a machete. Not only is this very dangerous, resulting in frequent injuries, but the beans themselves are often cut as well, so that they can no longer be fermented.

"The cocoa peeling machine must be able to work without electricity. It must also be small so that it can be easily transported, and at the same time, it must not be too expensive "

A ten-member team consisting of eight mechanical engineering students and two advisors from the Technical University of Munich is working on this challenge, and the Green Innovation Centers are helping them. In the course of a seminar, they designed a machine to peel the husks more safely and more efficiently. The latter is especially crucial, since the quality of the cocoa pods decreases rapidly after three days. The machine has to account for the unique conditions in Cameroon: "The cocoa peeling machine must be able to work without electricity. It must also be small so that it can be easily transported and at the same time it must not be too expensive," explains Patrick Lüftenegger of TU Munich. That means measuring the width, length, weight, circumference and thickness of the various pods, and then developing and testing appropriate models.

 The centerpiece: a 3D-printed wedge knife

Two possible models have won out: the first model is placed on the ground and operated with a lever. It has a magazine which can hold multiple pods, and can peel a single pod in just 5.6 seconds. The second model, on the other hand, is attached to a tree. While this method is somewhat slower than the first, with a maximum speed of 7.7 seconds, it requires less power and, purely theoretically, could also be extended with a magazine. The centerpiece of both designs is a wedge knife which the students designed themselves using a 3D printer. This allows the machine to cut open cocoa pods without splitting them completely or damaging the valuable beans.

 But the students are looking far beyond technical questions. In addition to questions of ergonomics, they are particularly concerned with the social impact of their machine, and especially with the question as to whether it might result in jobs being lost. "This danger does not exist," says Andrea Wihelmi-Somè, Project Manager at the Green Innovation Centers and reassures them: "This danger does not exist, because children are usually hired to peel cocoa in Cameroon, and they would otherwise be in school." Moreover, the idea is that the cocoa peeling machine will create new jobs in the service sector, as it will allow young entrepreneurs to offer cocoa peeling as a service.

What's important, the students and GIZ employees agree, is working together with Cameroonian cocoa farmers. To this end, a workshop with them will be held in Cameroon in the near future in order to clarify the many open questions and develop new ideas.

The commitment of the students is remarkable. In their project, they deal very intensively with issues of development and agricultural policy, as well as the conditions created by the local culture. "What the team found especially interesting were the role playing games," said Patrick Lüftenegger: "For example, we placed ourselves in the position of the older farmers. We wanted to understand the problems they had to contend with when peeling cocoa, how the cocoa peeling machine can solve these problems and what motivation the farmers have to use this innovation." In doing so, they are demonstrating how important it is to learn from other disciplines and to look at things from a different perspective.

A Report by Thorben Persch