Química Nova

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13323

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Autor: search.filters.author.Farah, AdrianaData final: 2009

Resultados da Pesquisa

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    Composição volátil dos defeitos intrínsecos do café por CG/EM-headspace
    (Sociedade Brasileira de Química, 2009) Bandeira, Raquel D. C. C.; Toci, Aline T.; Trugo, Luiz C.; Farah, Adriana
    About 20% of Brazilian raw coffee production is considered inappropriate for exportation. Consequently, these beans are incorporated to good quality beans in the Brazilian market. This by-product of coffee industry is called PVA due to the presence of black (P), green (V) and sour (A) defective beans which are known to contribute considerably for cup quality decrease. Data on the volatile composition of Brazilian defective coffee beans are scarce. In this study, we evaluated the volatile composition of immature, black-immature, black defective beans and PVA compared to good quality beans. Potential defective beans markers were identified.
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    Efeito do processo de descafeinação com diclorometano sobre a composição química dos cafés arábica e robusta antes e após a torração
    (Sociedade Brasileira de Química, 2006) Toci, Aline; Farah, Adriana; Trugo, Luiz Carlos
    The decaffeinated coffee market has been expanding increasingly in the last years. During decaffeination, aroma precursors and bioactive compounds may be extracted. In the present study we evaluate the changes in the chemical composition of C. arabica and C. canephora produced by decaffeination using dichloromethane. A significant change in the chemical composition of both C. arabica and C. canephora species was observed, with differences between species and degrees of roasting. Major changes were observed in sucrose, protein and trigonelline contents after decaffeination. Changes in the levels of total chlorogenic acids and in their isomers distribution were also observed. Lipids and total carbohydrates were not affected as much. The sensory and biological implications of these changes need to be investigated.