Coffee processing is the process of converting the coffee cherry into green coffee bean after the fruit or pulp has been removed. Farmers in West Guji zones lost out because of the lack of value-adding technologies, which resulted in low quality and profit. The on-farm evaluation of Jimma model engine operated double disc coffee pulpier was undertaken at Adola Redde Woreda, Guji Zone to evaluate its performance under different operational parameters. A 3x3 factorial experiment in Completely Randomized Design (CRD) was used to determine the effects of disc speed (100, 200, 300 rpm) and feeding rate (6, 9, 12 kg/min) on pulping capacity, efficiency and mechanical damage. The results showed that both factors have a significant effect on machine performance. The pulping capacity was increased with increase in disc speed and feeding rate and attained maximum of 531.38 kg/hr at 300 rpm and 12 kg/min. However, the highest pulping efficiency (96.24 %) and the least mechanical damage were obtained at 200 rpm and 6 kg/min feeding rate. The study concluded that the Jimma model double-disc pulpier performs best at a disc speed of 200 rpm and a feeding rate of 6-9 kg/min and can be a good alternative for smallholder farmers to improve the quality and efficiency of wet coffee processing and hence improve market competitiveness and income.

Keywords: Adola Redde, Coffee, Coffee Processing, Double-Disc Pulpier, Guji, Jimma Model, Mechanical Damage, On-Farm Evaluation, Pulping Capacity, Pulping Efficiency.

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Source of Funding:

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Competing Interests Statement:

The authors declare that they have no competing interests related to this work.

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Authors' contributions:

All the authors made an equal contribution in the Conception and design of the work, Data collection, Drafting the article, and Critical revision of the article.

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Acknowledgement:

Authors acknowledge the support and hard work from all those who helped in this study.