INFLUÊNCIA DO PROCESSAMENTO DO CAFÉ SOLÚVEL NO PERFIL E TEORES DE AMINAS BIOATIVAS LIVRES E CONJUGADAS

Abstract

O objetivo do presente trabalho foi avaliar a influência das etapas do processamento no perfil e teores de aminas bioativas livres e conjugadas no café solúvel. Amostras foram coletadas durante o processamento do café solúvel em três dias diferentes, em quatro pontos da linha de produção, incluindo grãos de café cru, grãos de café torrado, extrato de café e café solúvel. As aminas foram determinadas por CLAE – par iônico, derivação pós-coluna com o-ftalaldeído e detecção fluorimétrica a 340 nm de excitação e 445 nm de emissão. O processamento afetou o perfil e os teores das aminas bioativas livres e conjugadas no café solúvel. As aminas livres espermidina (EPD), espermina (EPM), putrescina (PUT), tiramina (TIM), serotonina (SRT) e triptamina (TRM) foram detectadas nos grãos de café cru, porém somente baixos teores de serotonina e agmatina (AGM) foram encontrados no café torrado. Após a extração, os níveis destas aminas aumentaram. No café solúvel foram encontradas as aminas livres EPD, EPM, TIM, SRT e TRM. As aminas conjugadas não foram detectadas no café solúvel. As poliaminas conjugadas putrescina, espermidina e espermina foram encontradas nos grãos de café cru e em baixos teores no café torrado.

The objective of this study was to investigate the influence of the processing steps on the profile and levels of free bioactive amines in instant coffee. Samples were collected at an instant coffee processing plant in three different days, at different stages of processing, including green coffee beans, roasted coffee, concentrated coffee and instant coffee. Amines were determined by ion pair-HPLC post column derivatization with o-phthalaldehyde and fluorimetric detection at 340 nm of excitation and 445 nm of emission. Processing significantly affected the profile and levels of amines in instant coffee. Spermidine (SPD), spermine (SPM), putrescine (PUT), tyramine (TYM), serotonin (SRT) and tryptamine (TRM) were detected in the green coffee beans, however only low levels of SRT and agmatina (AGM) were detected in the roasted beans. After extraction, the levels of these amines increased. Instant coffee had only TYM, SPD, SPM, SRT and AGM. The conjugated amines were not detected in the instant coffee. The conjugated polyamines PUT, SPD and SPM were detected only in green coffee beans and low levels in the roasted beans.