This work aimed to evaluate the physicochemical changes during the roasting process of Robusta and Arabica coffee. The highest content of total phenolics was detected in roasted coffee at temperatures of 135 °C/20.20 min, 210 °C/9.02 min, 210 °C/11.01 min, and 220 °C/13.47 min for both species. Robusta coffee showed greater antioxidant activity compared to Arabica coffee, except for the profiles at 230 °C/17.43 min and 275 °C/7.46 min that did not differ between samples by the DPPH and FRAP methods. For Arabica coffee, the antioxidant activity was independent of the roasting profile used. Robusta coffee presented higher values of the indexes b* (intensity of yellow vs blue), c* (chroma) and hue, being characterized as lighter and with greater chroma and hue. The highest levels of caffeoylquinic acid (5-CQA) were observed in Robusta coffee. Arabica coffee had lower trigonelline values. Caffeic acid and hydroxymethylfurfural were identified only in Robusta coffee. However, the results provided solid knowledge for the design of general properties and chemical compounds generated from binomials of roasting time and temperature that are little used in the world market.
Cocoa beans contain a variety of nutritional compounds and are rich in biologically active substances. The aim of this study was to utilize cocoa nibs (roasted and unroasted) as the main ingredient in the development of an attractive and convenient product. The produced nibs were analyzed for total phenolics, flavonoids, and antioxidant capacity using DPPH, ABTS, and FRAP methods. The primary phenolic compounds and methylxanthines were analyzed by LC/MS. Subsequently, cereal bars were developed, including a control sample (without nibs) and five formulations containing 41% nibs, using various proportions of roasted and unroasted nibs. The influence of the origin of the beans on the product characteristics was also evaluated. The results showed that the roasting process led to a reduction in epicatechin, caffeine, and caffeic acid. Furthermore, the reduction in total phenolics, flavonoids, and antioxidant capacity after roasting was more pronounced in beans from Bahia compared to those from Espírito Santo. Regarding the cereal bars, the results demonstrated that using cocoa from Bahia, the formulation with a higher proportion of unroasted nibs (F80) significantly increased the total phenolic content (1968.85 mg of gallic acid/100 g) and total flavonoids (39.26 mg of quercetin/100 g). This initial study suggests that the use of cocoa nibs as a functional ingredient in cereal bars may be a viable and advantageous option for creating a product with greater antioxidant potential.
The objective of this study was to evaluate sensorially, by professional Q-Grader, the beverage coffee from fermentation natural and fermentation with the use of yeasts and lactic acid bacteria as starter cultures in wet coffee processing. The Arabica coffee was harvested at two different altitudes in Espírito Santo State. Both coffees went through 04 treatments: inoculated with starter cultures Saccharomyces cerevisiae (YML) or Pediococcus acidilactici CCT 1622 (LAF), natural fermentation (NF) (not inoculated) and Control, without fermentation (WF). The coffee was processed by just the wet process. After process and roasting, the sensorial analysis was performed to understand the impact of fermentation processing in the coffee quality, and was performed by 6 Q-Graders, following SCA protocol. The study evidenced that the use of natural fermentation or starter cultures during post-harvest coffee contributed to obtain a quality beverage with pleasurable sensorial characteristics, punctuated by the tasters in the overall score obtained and also by the highsensory scores in attributes such as fragrance, acidity, aftertaste and the different perceived aromas. This work demonstrates for coffee growers that fermentation technology is not intuitive but requires an understanding of the relationship of the microorganisms with the coffee and the environment. In addition to the other chemical aspects of roasting and brew coffee. Key words: Fermentation; Microorganisms; Quality.
The physicochemical changes during the roasting process of Robusta and Arabica coffee were investigated. The highest content of total phenolics was detected in roasted coffee at temperatures of 135 °C/20.20 min, 210 °C/9.02 min, 210 °C/11.01 min, and 220 °C/13.47 min for both species. Robusta coffee showed greater antioxidant activity compared to Arabica coffee, except for the profiles at 230 °C/17.43 min and 275 °C/7.46 min that did not differ between samples by the DPPH and FRAP methods. For Arabica coffee, the antioxidant activity was independent of the roasting profile used. Robusta coffee presented higher values of the indexes b*, c* and hue, being characterized as lighter and with greater chroma and hue. The highest levels of 5-CQA were observed in Robusta coffee. Arabica coffee had lower trigonelline values. Caffeic acid and hydroxymethylfurfural were identified only in Robusta coffee. However, the results provided solid knowledge for the design of general properties and chemical compounds generated from binomials of roasting time and temperature that are little used in the world market.