RESUMO
In the present work we aimed to demonstrate the influence of inoculum starter in support high quality fermentation. Cocoa fermentations were performed in wooden boxes and eight yeasts strains were used in separated fermentations of fine cocoa, type Scavina, as starter inoculum. Temperature, pH, titirable acidity, reducing sugar and free amino acids were evaluated during or after fermentation. The influence of starters yeasts on the decrease of acidity, sugar concentration and free amino acids was significant. The strains Candida parapsilosis, Torulaspora delbrueckii and Pichia kluyveri showed greater changes in the reducing sugar and free amino acids in fermented cocoa beans. These results indicate the ability of yeast used as inoculum starter to modify the end condition and further enhance the quality of fine cocoa beans.
Assuntos
Cacau , Microbiologia de Alimentos/métodos , Leveduras , Aminoácidos/análise , Aminoácidos/metabolismo , Cacau/química , Cacau/metabolismo , Candida parapsilosis/genética , Candida parapsilosis/metabolismo , Chocolate , Fermentação , Concentração de Íons de Hidrogênio , Pichia/genética , Pichia/metabolismo , Sementes/química , Sementes/microbiologia , Temperatura , Torulaspora/genética , Torulaspora/metabolismo , Leveduras/genética , Leveduras/metabolismoRESUMO
Aim of this work was to study the impact of mixed cultures of Saccharomyces cerevisiae and Torulaspora delbrueckii and T. delbrueckii monoculture on the fermentation process conducted on two different cocoa hybrids, PS1319 and SJ02, in Bahia, Brazil. This was performed throughout studying physico-chemical changes during the fermentation process and analyzing volatile compounds and sensory analysis of chocolates. (GTG)5-PCR fingerprinting was used to type isolates at strain level allowing to assess the implantation of the starter cultures added. Resulted clusters were composed by T. delbrueckii strains isolated during the first 24h of fermentation. On the contrary, S. cerevisiae, the most strongly fermenting ethanol-tolerant species, took over the fermentation at a second stage. Quantification data of T. delbrueckii during spontaneous fermentation confirm the attitude of this species of not being so commonly involved in this process. This study also showed that the inoculum influenced the PS1319 hybrid end-product quality, changing analytic profile and sensory perception of chocolates. No big influences were recorded for SJ02 hybrid, but this may be improved. In combination with S. cerevisiae, T. delbrueckii had a positive influence on the analytical profile of chocolates. The application of starter cultures did change the aroma profile of the resulting chocolate as determined by GC-MS; in some case the differences observed had a significantly impact on the consumer perception of the chocolates.