The objective of this study was to discriminate between coffee brews prepared using Arabica and Robusta beans with particular emphasis on their diterpene esters content -cafestol and kahweol linoleate, oleate, palmitate and stearate-. HPLC-DAD was used for the quantification of free diterpenes. Setting the wavelength at 290 nm allows quantification of only kahweol esters while at 225 nm, co-elution occurs. Spectral deconvolution was used as a potential alternative for baseline separation of these compounds. To the best of our knowledge, quantification of diterpene esters through deconvolution approach for discrimination of Arabica and Robusta coffee brews was not documented so far. For this purpose, Arabica and Robusta coffee were used for several coffee brews preparation namely, boiled, French press, mocha and filter with coffee/water ratio of 7.5 g/100 mL. Diterpene esters were extracted directly using two sequential extractions with diethyl ether. Chromatographic analysis was performed using an HPLC-DAD at 225 and 290 nm for cafestol and kahweol esters, respectively and exported data were mathematically separated using spectral deconvolution. When comparing coffee species, our results indicated high concentration of cafestol and kahweol esters in Arabica brews while Robusta samples exhibited mainly cafestol esters. When considering the brewing procedure, in both species, the boiled extraction was the most efficient method in terms of diterpene esters content. Besides that, we found palmitate esters in higher content than other esters. A point emerging from our research is that spectral deconvolution could be useful for separation of co-eluting compounds as a cost effective alternative for other analytical techniques like LC-MS. In addition, since Robusta coffee brews contain mostly kahweol esters, this study open a series of investigation to evaluate the effect of these compounds on human health. The diterpene esters content can vary significantly with the preparation, allowing to optimize the concentration to the desired purpose.

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