| Title: | Influence of yeast inoculation on the quality of fermented coffee (Coffea arabica var. Mundo Novo) processed by natural and pulped natural processes |
| Author(s): | Bressani APP; Martinez SJ; Sarmento ABI; Borem FM; Schwan RF; |
| Address: | "Food Science Department, Federal University of Lavras, CEP 37200-000 Lavras, MG, Brazil. Biology Department, Federal University of Lavras, CEP 37200-000 Lavras, MG, Brazil. Bourbon Specialty Coffees, CEP 37701-24 Pocos de Caldas, MG, Brazil. Engineering Department, Federal University of Lavras, CEP 37200-000 Lavras, MG, Brazil. Biology Department, Federal University of Lavras, CEP 37200-000 Lavras, MG, Brazil. Electronic address: rschwan@ufla.br" |
| DOI: | 10.1016/j.ijfoodmicro.2021.109107 |
| ISSN/ISBN: | 1879-3460 (Electronic) 0168-1605 (Linking) |
| Abstract: | "Starter cultures during fermentation of Coffea arabica var. Mundo Novo processed in open stainless-steel vessels by natural and pulped natural methods were studied. The yeasts Meyerozyma caribbica (CCMA 0198), Saccharomyces cerevisiae (CCMA 0543), Candida parapsilosis (CCMA 0544), and Torulaspora delbrueckii (CCMA 0684) were inoculated separately in two different coffee processes: natural and pulped natural. The qPCR (real-time quantitative polymerase chain reaction) was used as a culture-independent method to monitor the inoculum's permanence. Changes in microbial metabolites (organic acids and volatile) production were evaluated by high-performance liquid chromatography (HPLC) and gas chromatograph-mass spectrometry (GC-MS), respectively. The sensory analysis was assessed in roasted beans. The fermentation lasted 27 h, and the coffee temperature ranged from 16.5 to 24.0 degrees C. The starter culture population was dominant throughout fermentation. S. cerevisiae (CCMA 0543) and T. delbrueckii (CCMA 0684) presented a higher population in natural processing. However, in pulped natural processing, M. caribbica (CCMA 0198) and C. parapsilosis (CCMA 0544) were the dominant populations. Citric, malic, and succinic acids were naturally present in coffee. Lactic, isobutyric, and isovaleric acids were detected at the end of the fermentation in different treatments. Lactic acid was detected in samples at the end of fermentation in Control and CCMA 0198 treatment. NAT coffee inoculated with CCMA 0684 presented isobutyric acid and isovaleric acid concentrations. Volatile compounds, such as 2,6-diethylpyrazine was detected in treatments inoculated with yeasts, but not in Controls. 2-acetoxymethylfuran was only detected in samples inoculated with CCMA 0198 from both NAT and PN methods. Samples fermented with S. cerevisiae (CCMA 0543) presented the highest sensorial scores in both processing (84.75 and 84.92). The inoculated coffee beans showed higher scores of sweetness, long aftertaste, and greater complexity. The starter cultures influenced the sensorial profiles through the synthesis of specific volatile constituents. However, considering all parameters analyzed, S. cerevisiae (CCMA 0543) would be the most suitable yeast for the var. Mundo Novo processed by both fermentation methods" |
| Keywords: | Acids/analysis Bioreactors/*microbiology Coffea/chemistry/*microbiology Fermentation Food Handling/*methods Sensation Species Specificity Taste Volatile Organic Compounds/analysis Yeasts/classification/isolation & purification/*metabolism Coffee fermentat; |
| Notes: | "MedlineBressani, Ana Paula Pereira Martinez, Silvia Juliana Sarmento, Andreia Braga Inacio Borem, Flavio Meira Schwan, Rosane Freitas eng Netherlands 2021/03/05 Int J Food Microbiol. 2021 Apr 2; 343:109107. doi: 10.1016/j.ijfoodmicro.2021.109107. Epub 2021 Feb 18" |
