Improving Processing Technologies: Cacao Beans Phase One

THE PROBLEM

Based on data from the Bali Agricultural Agency, more than 80% of cacao production in Bali comes from smallholder farmers. Cacao is largely grown and dried in Bali using traditional methods which involve laying the beans outside on a dry surface under the sun. This is done on a small scale and has risks related to weather and animals, and can produce a lower quality output.

Cacao is rising to become one of Bali’s major commodities. However there is little knowledge and little investment in learning the best way to process this product to increase its quality and in turn its value for smallholder farmers. When cacao is fermented and then dried, the flavour develops and the beans can be used to produce chocolate. In general, fermented beans fetch a much higher price than unfermented beans.

We believe that if farmers can ferment the beans before drying them, the quality will improve. We also believe that by using a Hybrid Solar Dryer, we can improve the efficiency and quality of the cacao beans, when compared to traditional drying methods.

THE SOLUTION

There are some simple technologies currently available that can increase the productivity of cacao processing and possibly increase the quality of dried cacao beans.

We will modify a standard fermentation box, creating a three-tier design aimed at making use of gravity to help farmers move large quantities of cacao beans more easily from one box to the next as they undergo the different stages of fermentation. We hope this newly designed box allows the farmer to ferment larger quantities of beans at one time, increasing their productivity.

We will also create a Hybrid Solar Dryer that ordinarily uses heat from sunlight but is also equipped with a biomass stove that can be used on cloudy days or at night time. We will be testing the efficiency of the solar drying process ensuring it is quicker than traditional methods and that it removes enough moisture to protect the quality of the beans.

We will process 250 kilograms of fresh cacao beans using the proposed technology to conduct our experiment. We will then compare the following:

1. The quality and efficiency of the fermentation process using the three-tier fermentation box versus the current fermentation box (single tier);

2. The quality and efficiency of the drying process using the Hybrid Solar Dryer versus the traditional open air drying method.

Kopernik’s project team will check the cacao after completing each processing method and measure the following:

1. Fermentation

• Temperature (celsius)
• Visual quality using cut-test method
• Flavour

1. Open air drying

• Temperature (celsius)
• Moisture content
• Number of drying days needed

1. Hybrid Solar Dryer

• Temperature (celsius)
• Moisture content
• Drying quality (defect beans)
• Flavour characteristics
• Number of drying days needed

The sampling method used will involve testing a sample from five random locations once the beans have completed the processing steps.

This project is the first phase of experimenting with cacao processing technologies and will concentrate on testing, gathering insights & making recommendations. Results will be analyzed and documented by the team.

THE EXPECTED IMPACT

If the results from this first phase are promising, Kopernik tends to develop further strategies to provide advantages to smallholder farmers growing cacao.

We believe that if farmers can ferment the beans before drying them, the quality will improve. We also believe that by using a Hybrid Solar Dryer, we can improve the efficiency and quality of the cacao beans, when compared to traditional drying methods.

THE PROJECT RESULT

This project took place in Angkah village, Selemadeg Barat district, Tabanan, the second largest cacao producing regency in Bali.¹ The project began with a needs assessment to map out the traditional pre and post-harvesting processes of the cacao bean. An experiment lasting 11 days tested whether a solar dryer could improve the drying process for a cacao processing cooperative, UPH Subak Abian Buana Mekar. Kopernik introduced the Hybrid Solar Dryer (HSD) and a three-tier fermentation box.

Our hypothesis was that a Hybrid Solar Dryer (HSD) will reduce the drying time for cacao when compared to the traditional floor drying method.

The experiment actually disproved our hypothesis with the moisture level of the beans in the HSD being two times higher than the beans dried using the Floor Solar Drying (FSD) method after the five day drying period.

The reason being that the humidity level inside the HSD was higher than the outdoor humidity level due to poor air circulation inside the dryer.

THE BROADER IMPACT

Download the project report above to read more