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Item Specialty coffees fermented at different altitudes: Influence of yeast co-inoculation on chemical and sensory composition(Universidade Federal de Lavras, 2021-04-26) Bressani, Ana Paula Pereira; Schwan, Rosane Freitas; Simão, João Batista Pavesi; Batista, Nádia NaraSpecialty coffees are gaining more space in the Brazilian market, and the changes in production, processing, marketing, and consumer culture are noticeable. Unquestionably, the use of selected starter cultures in the fermentation process improves the coffee quality. However, the microorganisms' behavior can be different depending on the variety, processing method, and altitude. Thus, this paper aims to (i) use metabolomics, chemical, and sensory methodologies to evaluate the quality of fermented coffees of the cultivar Catuaí vermelho IAC-44 at different altitudes (600 and 1,200 m) located in the Caparaó region. (ii) analyze consumers’ knowledge and perspectives on coffees and investigate how information can influence consumers’ sensory experience. For this, the coffee cherries were harvested manually and separated into batches of 20 kg, representing seven treatments plus control at each altitude. The starter cultures - Saccharomyces cerevisiae CCMA 0543, Candida parapsilosis CCMA 0544, and Torulospora delbrueckii CCMA 0684 - were inoculated, isolated, and in co-inoculation. The control was performed without inoculation. Fermentation of whole fruits lasted 72 h in closed bioreactors. Then, the coffees were transferred to the suspended terraces until 11- 12% moisture. Samples were collected and frozen for chemical analysis. We studied the improving coffee beverage quality cultivated at low altitudes through inoculation of yeast during fermentation in dry processing. The analyzes were performed using liquid and gas chromatography, Fourier transforms infrared spectroscopy (FTIR), and cup testing. Differences in chemical compounds were observed between the inoculated coffees and the control, both for green and roasted beans. Fermentation improved the quality of low-altitude coffees, and the co-inoculation of non-Saccharomyces yeasts (C. parapsilosis CCMA 0544 and T. delbrueckii CCMA 0684) had the highest sensory score (85), being the most suitable for this process. The second topic addressed in this work was the influence of fermentation with starter cultures concerning the bioactive, chemical, and sensory compounds of coffee produced at high altitudes. The content of total polyphenols and antioxidants is strongly correlated with the end of fermentation in a closed bioreactor and after roasting. The trigonelline content has a moderate and negative correlation with fermentation and roasting. Fruity, citric, and wine notes were found only in inoculated treatments. The co-inoculated with the three yeasts showed the highest sensory score (86.9). The third aspect addressed was understanding the perspectives and desires of coffee consumers through a questionnaire in a digital format with 1,005 participants. The chocolate flavor is still the most expected in specialty coffee. The Check-all-that-Apply (CATA) test was carried out with 101 consumers using the same coffee (without and with information). Sensory analysis showed that consumers could be influenced by information. Therefore, co-inoculation of yeasts in coffee fermentation is a promising alternative for low and high-altitude coffee. Also, specialty fermented coffees should be made more widely available to consumers.Item Application of microrganisms for coffee fermentation(Universidade Federal de Lavras, 2018-03-23) Ribeiro, Luciana Silva; Schwan, Rosane Freitas; Evangelista, Suzana Reis; Miguel, Maria Gabriela da Cruz PedrozoArabica coffees of three varieties present distinct results when inoculated with microorganisms. The attempt to improve coffee quality can be implemented at different stages of coffee production. Presence of microorganisms during coffee fermentation directly interferes with the quality and characteristics of final beverage. The aim of this study was to evaluate the effect on coffee quality of inoculation of different microorganisms and also to study a bacteriological composition of coffees processed by wet fermentation. Three varieties of coffees studied at work: Ouro amarelo, Mundo novo and Catuaí Vermelho, mining region (Cerrado Mineiro and Southern of Minas Gerais). Ouro amarelo and Novo mundo processed by semi-dry method inoculated with three yeast strains (Saccharomyces cerevisiae CCMA 0200 and CCMA 0543; Torulaspora delbrueckii CCMA 0684). Two sensory analysis techniques were used (Cup Test and Temporal Dominance of Sensations). It was possible to observe that Ouro Amarelo variety obtained higher scores for evaluated attributes. The use of the CCMA 0543 and CCMA 0684 strains improved the sensory quality of the beverages. The second aspect discussed in this work is the diversity and effect of the inoculation of bacteria in fermentation of coffee by the wet process. Initially, a bacterial diversity was studied (Ouro amarelo, Mundo Novo and Catuaí Vermelho). Through identification techniques such as MALDI-TOF (Array Assisted Laser Desorption / Ionization - Time of Flight) and sequencing it was possible to identify 41 species of bacteria. In addition, some target compounds were quantified through HPLC (High Performance Liquid Chromatography) and CG-MS (Gas Chromatography and a mass spectrometer). According to the results, Lactobacillus plantarum and Leuconostoc mesenteroides were found in all varieties. Citric acid was detected at high concentrations and as the main classes of volatiles found were acids, alcohols, aldehydes and hydrocarbons. The sensorial profile demonstrates the presence of sensations of acidity (Ouro amarelo and Catuaí vermelho), bitterness, chocolate and nuts (Novo mundo) and sweetness (Catuaí vermelho). And finally, some species tested for their fermentation capacity to be applied as a starter culture in coffee of the Catuaí vermelho, in wet fermentation process. Strains Pantoea dispersa CCMA 1203; Cellulosimicrobium cellulans 1186, L. mesenteroides CCMA 1105 and L. plantarum CCMA 1065 presented better results in relation to acid production and changes in volatile profile during fermentation. These strains are strongly selective to be as well as starter cultures in wet fermented coffee. However, it is concluded that the inoculation of microorganisms in coffee is a highly promising alternative, being dependent on the variety and type of processing to be applied.