Coffee Science

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Resultados da Pesquisa

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    Antioxidant Activity and Phytochemicals of Freeze-dried and Spray-dried Soluble Coffee Brews
    (Editora UFLA, 2025-05-19) Susilawati, I Dewa Ayu; Muzeka, Fredi
    This study analyzed the antioxidant activity and the concentration of several phytochemicals i.e. polyphenols, caffeine, glutathione (GSH), and protein, of freeze-dried and spray-dried soluble coffee brews. Six types of coffee samples were analyzed i.e., 1) Spray-Dried Robusta instant coffee (SDR), 2) Freeze-Dried Robusta instant coffee (FDR), 3) Regular Robusta coffee powder (RR), 4) Spray-Dried Arabica instant coffee (SDA), 5) Freeze-Dried Arabica instant coffee (FDA), and 6) Regular Arabica coffee powder (RA). Antioxidant activity was determined using the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging assay. Polyphenols, caffeine, glutathione, and protein were measured spectrophotometrically. Results showed that freeze-dried instant coffee (both robusta and arabica) in a concentration of 500 ppm demonstrated DPPH radical scavenger activity >80% and significantly higher (p<0.05) compared to spray-dried soluble coffee and regular coffee brews. This level was maintained in concentrations of 750 ppm, 1000 ppm, and 1500 ppm. The higher antioxidant activity of freeze-dried coffee brew was in line with the higher concentration of polyphenols, caffeine, GSH, and protein. In conclusion, freeze-dried instant coffee demonstrated more sensitive antioxidant activity, probably due to its more abundant polyphenols, caffeine, GSH, and protein.
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    Free radical scavenging activity-based antioxidant analysis and infrared spectroscopy of peppermint-flavored coffee drink
    (Editora UFLA, 2024-12-05) Kustyawati, Maria Erna; Nurdin, Samsu Udayana; Thaliarinanta, Angela Saraz
    Peppermint essential oil canserve as a healthy flavoring additive to coffee drinks and provide health benefits by enhancing their antioxidant activity. Hence, this study aimed to examine the antioxidant activity of peppermint-flavored coffee drinks using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azinobis-(3-ethylenebenzothiazoline)-6-sulfonic acid (ABTS) free radical scavenging assays. Furthermore, Fourier transform infrared-attenuated total reflectance spectroscopy was performed to investigate the profile of compounds contributing to the antioxidant property. The experiments were conducted using a Complete Randomized Block Design with six replications. Two-factor treatments were as follows: soaking time (S), 0 (S0), 5 (S1), and 10 (S2) min; peppermint essential oil concentration (E), 0 (E0), 0.5 (E1), and 0.75% (E2) (v/v). N otably, both DPPH and ABTS assays revealed increased antioxidant activity of peppermint-flavored coffee drink where the coffee was soaked for 10 min in 0.75% peppermint solution. The coffee soaked for 10 min in 0.5% and 0.75% peppermint solutions showed a high scavenging effect against ABTS free radical, with 93.73 and 94.30% inhibition activity and half-maximal inhibitory concentrations of 0.272 and 0.267 ppm, respectively. Additionally, a new peak was observed at 1640 cm−1in peppermint solution-soaked coffee beans,which corresponded tothe C=C functional group in the limonene spectrum, an antioxidant compound in peppermint. Altogether, the findings show that peppermint essential oil enhanced the antioxidant activity of the coffee.
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    Atividade antioxidante de cafés torrado e solúvel: padronização e validação de métodos
    (Editora UFLA, 2012-01) Vignoli, Josiane Alessandra; Bassoli, Denisley Gentil; Benassi, Marta de Toledo
    A atividade antioxidante (AA) de café, relacionada à presença de diferentes componentes, tem recebido grande atenção nos últimos anos e pode ser medida por diversos métodos. Entretanto, pouco se sabe sobre a eficiência dos métodos utilizados na avaliação da AA dos cafés. Objetivou-se, neste trabalho padronizar e validar, para café torrado e para café solúvel, técnicas de medida da AA, como ABTS (TEAC), FRAP, Folin-Ciocalteau, DPPH e Deoxirribose. Os resultados indicaram que, todos os métodos de medida de AA testados são precisos e podem ser utilizados para avaliação, tendo apresentado coeficientes de variação entre 3,5 e 10%, considerando-se as duas matrizes (torrado e solúvel) e as diferentes concentrações estudadas. A faixa de concentração empregada deve ser escolhida criteriosamente para cada matriz e método de interesse, uma vez que pode interferir, dependendo da metodologia utilizada, tanto em precisão quanto nos valores de AA observados.