Coffee Science
URI permanente desta seção${dspace.url}/handle/123456789/3355
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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 Comparison of sensory attributes and chemical markers of the infrared spectrum between defective and non-defective Colombian coffee samples(Editora UFLA, 2020) Rodriguez, Yeison Fernando Barrios; Calderon, Karen Tatiana Salas; Hernández, Joel GirónDefects in coffee affect the sensory quality of finished drink. To avoid this, defective beans are usually removed after threshing, as, once the green beans have been roasted, it becomes difficult to identify the defects. Procedures have been developed to evaluate coffee samples using infrared spectroscopy to detect such defects. As such, this study evaluated infrared spectra and sensory attributes of 39 coffee samples in: commercial ground and instant coffees, medium and high roast quality coffees, and defects present in the coffee. The sensory analysis was performed by 10 judges, semi-trained by a Q-grader, and eleven attributes were assessed using a semi-structured hedonic scale. The spectra obtained from the coffee samples were processed by mean centering, normalization (probabilistic quotient normalization), area normalization, first derivative and second derivative, later followed by principal component analyses. The sensory results showed differences in the evaluated attributes, differentiating between the samples of high quality medium roasted coffee from the other samples. After processing IR spectra of the samples by area normalization, PCA results exhibited four different groups: a) medium, high roasted quality coffee, with broken and chipped defects; b) commercial ground coffee and defects of sour, insect damaged, and faded; c) black defects, and d) instant coffee. Using the chemical descriptors obtained from the infrared spectra, it was possible to separate between high quality, commercial and instant coffee.