Aida Esther Penuela-Martinez
National University of Colombia at Medellin, Colombia
Title: Dynamics of different fermentation processes in coffee (Coffea arabica L. var Caturra) and its effect on the beverage quality
Biography
Biography: Aida Esther Penuela-Martinez
Abstract
Acidity in coffee is an attribute which at appropriate leaves contributes to beverage quality. Arabica coffee processed by the wet method has been classified as better acidity, in this process, the fermentation stage plays an important role to improve this attribute due to the physical, chemical and biological factors involved. Different methods of coffee fermentation can affect the dynamics of the process and influence the final quality. In order to obtain the changes in pH, temperature and organic acid production, several coffee fermentative processes were evaluated. The effect on the final quality was also obtained. A completely randomized design was used, 2×3+2; two fruit fermentation times, three fermentation methods and two controls, one standard (traditional fermentation) and another negative (without fermentation). ANOVA, Duncan and Dunnett tests were used for data analysis. The results showed changes in pH from 5.86 at the beginning of the process to 3.73 at the end. The temperature in was between 21 °C and 19 °C while it increased to 25 °C for the traditional fermentation. The concentrations of lactic and acetic acids increased respect to the processing time while the citric and malic acids tend to decrease. Significant differences in the mean acids concentrations, mainly for acetic and lactic acids, were detected. By contrast, the quinic acid concentration remained constant in all fermentative processes assessed, including controls. Furthermore, the averages of quality values were significantly higher in fermentation processes coffee than the obtained with the controls. Coffee acidity was directly associated with acetic acid concentration. The changes detected in the evaluated variables indicate the metabolic activity of microorganisms involved in the fermentation, which can vary according to the method of coffee fermentation process applied. The coffee fermentation stage has potential which could be used as a strategy to improve product quality varying of the processing method.