Biochemical Components of Shaded Coffee under Different Management Levels

D.A Odeny,G.N Cheminingwa,S.I Shibairo,C.W Kathurima

doi:10.19026/ajfst.12.3063

Abstract

This study was conducted to evaluate the effect of management and shade levels on some biochemical components of coffee. The study was carried out at the Kenya Agricultural and Livestock Research Organization, Coffee Research Institute (KALRO-CRI) coffee farm in Bungoma County and two farmers’ fields in Bungoma County, representing high, medium and low management levels. The coffee management levels were categorized depending on field operations and application of inputs. The different shade levels were based on the distances from the shade tree trunk: 0-1.5, 1.5-3, 3-4.5, 4.5-6 m, respectively and coffee trees under full sun. The shading level was estimated by measuring the Photosynthetic Photon Flux Density in μmol m-2/s using a Line Quantum Sensor and expressing it as a percentage of that obtained under full sun. Fully ripe cherries were harvested, wet processed and the wet parchment dried to final moisture content of 10.5 to 11%. Caffeine, trigonelline, total chlorogenic acids, oil and sucrose were determined using specific methodologies and quantified on dry weight basis. The results showed that biochemical components were affected significantly due to shade and management levels. Most of the biochemical components were positively correlated with shade and management levels. This showed the possibility of manipulating the two parameters to enhance the quality of coffee.

Highlights

Coffee beans are the seeds of a perennial evergreen tropical plant, which belongs to the Rubiceae family and the genus Coffea (Davies et al, 2006)
High management level resulted to significantly higher caffeine content than medium management level which in turn had higher caffeine content than the low management level
Under the high management level, N fertilizers were applied as recommended and this probably led to higher caffeine content than under the lower level management where little or no inputs were applied at all

Summary

INTRODUCTION

Coffee beans are the seeds of a perennial evergreen tropical plant, which belongs to the Rubiceae family and the genus Coffea (Davies et al, 2006). The coffee beverage quality is based on the characterization of numerous factors including taste and aroma (Kathurima et al, 2009) which are related to biochemical contents of roasted coffee beans. The key biochemical compounds in coffee are caffeine, oils, trigonelline, sucrose and chlorogenic acids (Farah et al, 2006; Gichimu et al, 2014). Chlorogenic Acids (CGA) are an important group of non-volatile compounds in green coffee They are esters of trans-cinnamic acids, such as caffeic, ferulic and p-coumaric acids, with Quinic Acid (QA) (Clifford, 2000). They play an important role in the formation of roasted coffee flavour and have an influence in determining coffee cup quality (Farah et al, 2006). Biochemical analysis: Caffeine, trigonelline and total Chlorogenic Acids (CGA) were extracted simultaneously from 3g of green coffee powder using ethanol and acetone (24:1v/v) and shaking in the dark

MATERIALS AND METHODS

RESULTS AND DISCUSSION

DISCUSSION

CONCLUSION