Proceedings of the XLVII Italian Society of Agricultural Genetics - SIGA Annual Congress

Verona, Italy - 24/27 September, 2003

ISBN 88-900622-4-X

Poster Abstract - 5.43

MOLECULAR CHARACTERISATION AND TRACEABILITY OF PROCESSED COFFEE

S. Doveri*, L. Palmieri**, C. Martellossi***, G. Graziosi***, D. Lee*, P. Donini*

*) NIAB Huntingdon Road CB3 0LE Cambridge - UK

**) Dept of Environmental Science University of Parma, Parco Area delle Scienze 11/a, 43100 Parma, Italy

***) Dept of Biology, University of Trieste, Piazzale Europa 1, 34127 Trieste, Italy

coffee, quantitative PCR, SSR, microsatellite, traceability

Coffee products on the market are usually derived from one of two species: Coffea arabica (Arabica) and Coffea canephora (Robusta), or consist as a blend.

Robusta derives its name from its disease resistance properties. It delivers a strong, full-bodied coffee with a high caffeine content (4.5% compared to 1.7% for Arabica). Robusta coffee is characterised as “neutral” and weak-flavoured, while coffee obtained from Arabica is a milder, fruitier and acidulous beverage of higher quality. The market value of traded Arabica beans is higher than that of Robusta, thus there is business potential and commercial need for diagnostic tests that discriminate the two species both in starting raw materials and in final products.

Several reports exist on the determination of coffee species composition of products based on chemical analyses (caffeine, sterols, terpenic alcohol, minerals and phenolic acids). However, these methods suffer from severe limitations and are hardly suitable for quantifying species composition of blends.

One solution to the industry’s problems with authenticity is a DNA-based diagnostic test that would enable the buyer to determine the market value of traded commodities and serve as a quality assurance tool for guaranteeing products.

Our study illustrates the DNA-based approach to the determination of genetic identity of the two coffee species in blends, and the development of quantitative-PCR methods with the aim to quantify the presence of each species in a blend. SSR (microsatellite markers) analysis and the LightcyclerÒ PCR platforms have been used in our study on C. arabica and C. canephora.