Effect of maturity and the colour parameters on the cocoa opening force using the existing mechanical system

Amuaku Randy, Eric Amoah Asante, Emmanuel Y.H Bobobee, Jerry Oppong Adutwum and Godwin Amanor
Additional contact information
Amuaku Randy: Department of Agricultural and Biosystems Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
Eric Amoah Asante: Department of Agricultural and Biosystems Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
Emmanuel Y.H Bobobee: Department of Agricultural and Biosystems Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
Jerry Oppong Adutwum: Wood Physics and Drying Laboratory, CSIR-Forestry Research Institute, Kumasi, Ghana
Godwin Amanor: Department of Mechanical Engineering, Koforidua Technical University, Koforidua, Ghana

Research in Agricultural Engineering, vol. preprint

Abstract: The study assessed the mechanical and colorimetric properties of cocoa (Theobroma cacao L.) pods at various maturity stages to improve the mechanised pod-opening efficiency. Thirty pods, each replicated three times, underwent compressive loading and colour analysis using the CIE Lab* colour space to correlate the colour attributes with mechanical resistance. The pod maturity significantly (P < 0.05) influenced the opening force and compressive strength: unripe pods required the highest mean force (1 222 N) and strength (0.316 N.mm-2), while aged pods needed only 346 N and 0.094 N.mm-2. The longitudinal orientation yielded higher and more consistent force response than the transverse orientation, with the ANOVA confirming significant differences (P < 0.05). The colour parameters, especially yellowness (b*) and hue angle (H°), were strongly and negatively correlated with the mechanical properties (r ≥ -0.99, P ≤ 0.05), making them reliable non-destructive indicators of maturity. The Partial Least Squares Regression (PLSR) models validated the predictive power of the combined colour and mechanical data, with the longitudinal orientation producing the highest model accuracy across all the maturity levels. Combining the colour-based maturity assessment with mechanical testing provides a robust framework for designing automated, maturity-sensitive cocoa pod-opening systems that optimise the efficiency and reduce bean damage during post-harvest handling. The research approach provided an outstanding quantitative assessment.

Keywords: colour space analysis; compressive strength; orientation effects; postharvest mechanisation; ripeness indicators (search for similar items in EconPapers)
References: Add references at CitEc
Citations:

Downloads: (external link)
http://rae.agriculturejournals.cz/doi/10.17221/149/2025-RAE.html (text/html)
free of charge

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:caa:jnlrae:v:preprint:id:149-2025-rae

DOI: 10.17221/149/2025-RAE

Access Statistics for this article

Research in Agricultural Engineering is currently edited by Bc. Michaela Polcarová

More articles in Research in Agricultural Engineering from Czech Academy of Agricultural Sciences
Bibliographic data for series maintained by Ivo Andrle ().