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Item Antioxidant Activity and Phytochemicals of Freeze-dried and Spray-dried Soluble Coffee Brews(Editora UFLA, 2025-05-19) Susilawati, I Dewa Ayu; Muzeka, FrediThis 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.Item 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 SarazPeppermint 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.Item Stability of phenolic compounds and antioxidant capacity of regular and decaffeinated coffees(Instituto de Tecnologia do Paraná - Tecpar, 2014-01) Vicente, Silvio José Valadão; Queiroz, Yara Severino; Gotlieb, Sabina Léa Davidson; Torres, Elizabeth Aparecida Ferraz da SilvaThis study compared the regular and decaffeinated coffees in relation to antioxidant capacity, levels of some antioxidant molecules and stability of these parameters over a six-month period under different storage conditions. The regular coffee samples analyzed right after the industrial production showed higher antioxidant capacity (ORAC and DPPH), the same levels of phenolic compounds and higher levels of phenolic acids than decaffeinated coffee. After six months, the closed packs of both the grades kept under vacuum at 20°C did not show significant changes from the initial results; the open packs stored at 4°C showed small but statistically significant reductions and the open packs stored at 20°C showed higher and statistically significant losses (p < 0.05). Oxygen was the most important factor for these losses but temperature also played an important role. Tests showed that the storage conditions were very important to preserve the quality of coffees regarding the analyzed parameters.Item Análise de compostos bioativos, grupos ácidos e da atividade antioxidante do café arábica (Coffea arabica) do cerrado e de seus grãos defeituosos (PVA) submetidos a diferentes torras(Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2008-12) Morais, Sérgio Antônio Lemos de; Aquino, Francisco José Tôrres de; Nascimento, Evandro Afonso do; Oliveira, Grasielle Silva de; Chang, Roberto; Santos, Neide Carolina dos; Rosa, Gabriel MarquesO presente trabalho estudou os compostos bioativos (ácidos clorogênicos, trigonelina, cafeína, fenóis totais e proantocianidinas), grupos hidroxila ácidos e atividade antioxidante de um café arábica proveniente do Cerrado Mineiro e de seu PVA (grãos pretos, verdes e ardidos). As amostras foram preparadas nas torras clara (180 ± 10 °C; 6,0 ± 1,0 minutos), média (180 ± 10 °C; 8,0 ± 1,0 minutos) e escura (180 ± 10 °C; 10,0 ± 1,0 minutos). Considerando-se a média das três torras do café e do PVA, a diferença observada no teor de todos os constituintes acima não foi significativa (p > 0,05), exceto com o teor de grupos hidroxila ácidos que foi ligeiramente superior no PVA e cafeína calculada pelo método semiquantitativo que foi superior no café. Portanto, dentre esses constituintes, os compostos com grupos ácidos seriam os únicos que poderiam contribuir para explicar a grande diferença de sabor existente entre o café de grãos sadios e o de PVA. Tanto o café como o PVA apresentaram atividade seqüestradora do radical DPPH . nas três torras, sendo a atividade do café sempre superior. Analisando-se as variações dos teores de cafeína, fenóis totais, proantocianidinas, grupos hidroxila ácidos, trigonelina e ácidos clorogênicos, não foi possível explicar a atividade antioxidante superior apresentada pelo café da torra média (CE 50 de 2,3 mg.mg –1 de DPPH . ).Item 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 ToledoA 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.