Post-harvest processing and microbial fermentation of coffee fruits play an essential role in the metabolites formation that influence the nutritional and sensory quality of the beverage. Thus, the ...objective of this study was to analyze the effect of coffee cherries processing and fermentation conditions on the microbial communities and the chemical and sensory quality of the beverage. Induced fermentation changed in the bacteria and fungi communities (Treatments: T1, T3, and T7).
Klebsiella
sp. inoculation (T1) allowed an increase in richness of bacteria and 81 points in the sensory score over the fermentation time. However, there was a reduction in richness of microbial community in treatments with
Saccharomyces cerevisiae
(T3 and T7)
.
An increase in the indexes of microbial diversity was observed in 72 h in treatment with coffee pulp (T2). In treatment with coffee cherries and spontaneous fermentation (T4) had a higher sensory score than other treatments, indicating a sensory gain from 36 to 72 h. Coffee cherries with superficial disinfection (T5) had a reduction in microbial profile, but did not change the final score of the beverage over the 72 h. In T6 (floaters fruits) was observed an alteration in the fungal community (36–72 h) and the lowest sensory score. The impact of adding water on coffee fermentation was dependent on time (T3 and T7). Furthermore, 5-hydroxymethylfurfural has a positive correlation with the final score of the beverage. Thus, microbial profile and sensory score of beverages are dependent of conditions of processing of coffee fruits and fermentation.
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•Microbial richness increases depending on the condition of the fermentation.•Microorganisms actions could be correlated with sensory attributes.•Fermentation conditions promote ...sensory and chemical changes in coffee.
In view of the possibility of diversifying metabolic routes promoted by fermentation, this study proposed a new processing method for coffee, which consists of adapting a technique already consolidated in winemaking, carbonic maceration. The assay occurred under anaerobic conditions with different time and temperature fermentation. The aim of this study was to determine the differences in coffee characteristics (sensorial, chemical, and microbial) after carbonic maceration and fermentation. Specialty Coffee Association protocol, nuclear magnetic resonance, and denaturing gradient gel electrophoresis were used in these analyzes. A significant functional relationship between global score and temperature (38 °C), for the fermentation time of 96 h was observed. Bacterial diversity and sensory characteristics had a positive correlation. Furthermore, trigonelline, formic acid, hydroxymethylfurfural, lipids, and γ-butyrolactone also contributed to score and sensory quality of coffee beverage. Thus, our data show consistent factors to infer on the microbiological action on the sensory quality of coffee beverage.
Edaphoclimatic conditions, planting altitudes, soil, the microbiome of plants and fruits, genotypes, and postharvest processing are variables that contribute to the chemical and sensory quality of ...the coffee. Thus, the objective of this study was to evaluate the impacts of planting altitude and fermentation of fruits on the chemical and sensory quality of the coffee using Nuclear Magnetic Resonance (NMR) and Linear Discriminant Analysis (LDA). Cherry coffees were harvested in eight points of altitudes between 826 and 1078.08 m. A completely randomized design with e planting altitudes, five fermentation processes, and five repetitions was performed. Lipids, trigonelline, citrate, and malate were the compounds that most contribute to the chemical discrimination of coffee in the altitudes below 969 m. While, in the high altitudes (> 1000 m), this discrimination was due to the HMF, quinic acid, caffeine, and formic acid, and the global notes of coffee beverages were higher than 80 points. In fermented coffee, the LDA of the chemical data indicates the formation of five clusters, showing how the compounds can suffer changes depending on the form of processing used in coffee. The best score of beverage was observed in samples of 1078.08 m under dry fermentation and only in samples of 969 m was observed a significant difference in the sensory score between spontaneous fermentation and induced fermentation. Thus, coffee sensory scores were dependent on planting and fermentation methods and NMR and LDA techniques proved important in chemical and sensory discrimination of coffees.
The consumer market has a strong tendency to consume specialty coffees, making it essential to understand the influence of environmental conditions, such as solar radiation and altitude, on coffee ...quality. This study aimed to analyze the physical and sensory quality of Arabica coffee as a function of different altitudes and incident solar radiation on the coffee tree. The study was carried out in the city of Manhuaçu-MG, Brazil. Three altitudes (950, 1050 and 1150 m above mean sea level) and two sides of coffee exposure to solar radiation (east face: morning sun and west face: afternoon sun) were studied in two post-harvest processing (natural and peeled cherry). Sensory attributes, granulometry and occurrence of coffee defects were evaluated, in order to verify if there was variation in the physical and sensorial characteristics of the coffee. It was found that at an altitude of 1150mamsl, on the exposed face of the plant that received the afternoon sun, there was the formation of better-quality coffee, when compared to the face that received the morning sun. On the other hand, at lower altitudes, coffees from the face of the plant exposed to the morning sun showed a greater association with physical and sensory quality parameters.
Coffee is one of the most widely consumed beverages in the world. When compared to the arabica variety, robusta coffee has a lower market value due to several factors, especially those related to ...sensory analysis. Thus, this study examined fermentation processing techniques for Arabica and Robusta coffees using medium infrared analyzes to identify differences in their chemical compositions, which suggested specific fermentation routines for each variety. The samples of both varieties, collected in proper regions of the Brazilian state of Espírito Santo, were subjected to different wet-processing methods (Washed, Yeast fermentation, Dry fermentation, and Dry fermentation with yeast). The obtained spectra were divided into spectral regions, which were compared by specific statistical tests that revealed differences between them for the varieties and processing methods. Yeast Fermentation demonstrated to be the most recommendable processing technique for the robusta variety, considering the obtained secondary compounds associated with final coffee quality.
•Infrared spectroscopy and fermentation show similarities between arabica and conilon.•Statistical tests show differences in the structure of coffee varieties.•Secondary compounds generated by fermentation are related to coffee quality.•The induced fermentation approximates the quality of conilon to arabica coffee.
Ripening cycles of the coffee are important for planning the harvest and post-harvest processing of the fruit and influence the sensory quality of the coffee beverage. In the
Coffea arabica
, the ...number of these annual cycles depends on the edaphoclimatic conditions, soil microbiota, altitude, and genotype. In this study, we present in an unprecedented way how the microbial communities (bacteria and fungi) of the soil and fruits of the coffee tree and the quality of chemical and sensory of coffee fruits can change depending on the harvest season. We also evaluated whether there is a relationship between changes in microbial communities (soil and fruits) and chemical and sensory panels of the coffee in two seasons. Cherry coffee fruits sampling and soil were carried out in September and November which have different edaphoclimatic conditions. Profiles of the microbial community and chemical and sensory panels of the samples were performed using the DGGE technique, Mid-infrared spectroscopy, and Specialty Coffee Association protocols. Microbial communities (soils and fruits) profile was different between distinct sampling periods. Composition of the coffee varies with the harvest since the coffees harvested in September have higher concentrations of caffeine and chlorogenic acids and lower concentrations of proteins and lipids compared to the samples collected later. A correlation between infrared spectrum and microbial community was observed in the second harvest period which had a final sensory score higher than another harvest. These results show that edaphoclimatic factors and microbial communities can be associated with the final quality of the beverage.
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•1H NMR and advanced data analysis methods for evaluating fermented coffees.•Starter fermentation with Saccharomyces cerevisiae provided better sensory quality.•The chemical and ...sensory profiles of fermented coffees are correlated.•Lipids are important markers for the quality of fermented conilon coffee.
The potential impact of fermentation on coffee quality has been the target of several scientific studies. In this perspective, we present a design of different fermentation processes applied to coffees of the Coffea canephora var. conilon. Thus, coffee samples were submitted to six fermentation methods, at five different times (24, 48, 72, 96, and 120 h). Sensory analysis and hydrogen nuclear magnetic resonance (1H NMR) were used in roasted coffees, to understand aspects of quality and chemical profile, respectively. Variable selection by Fisher discriminant (FD), and multivariate data analysis, including principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and support vector machine (SVM) were used to extract the main chemical information and establish direct relationships with coffee sensory quality. The results indicated chlorogenic acids, caffeine, γ-butyrolactone, lipids, sugars, and acetic acid as responsible for the discrimination of the different fermentation processes. In addition, lipids were characteristic in coffees with higher sensory scores, indicating they are an important marker for the quality of the beverage.
Coffee is one of the most widely consumed beverages in the world. The genetic variability of
Coffea canephora
has demonstrated significant differences in the chemical compositions of genotypes, ...resulting in different sensory profiles in the beverage. Fermentation can also affect the sensory quality of coffee beverage. Therefore, the objective of this study was to analyze the sensory profile and the chemical groups that contribute to the sensory qualities of the coffee beverage of
C. canephora
var. Conilon genotypes subjected to different fermentation processes. Fermentations were carried out with 4 L of cherry coffee or peeled cherry coffee for 36 h at 25 ℃. In the induced fermentation, the initial Colony Forming Unit (CFU/mL) was of 10
7
for S
accharomyces cerevisiae
,
Klebsiella
sp, and
Lactobacillus brevis
. There was no microbial inoculation in the washed fermentation and the natural process. The sensory quality and chemical groups of the coffee were determined using the Uganda Coffee Development Authority Sensory Analysis Protocol with 6 Q-Graders and mid-infrared spectroscopy, respectively. The sensory and spectrometry analyses were able to distinguish the genotypes, highlighting the separations of genotypes A1 and Verdim with the worst sensory results, and genotype 153 with the best result. Groups formation through the mean Euclidean distance reinforces the sensory differences between fermentations. Furthermore, the greatest chemical changes in coffee beans were promoted by fermentation induced by
S. cerevisiae
. Thus, the genotypes and the type of fermentation influence in the sensory quality demonstrating potential for optimizing fermentations to improve the sensory quality of conilon coffee.
Ecological sustainability, productivity, and sensory quality of coffee fruits are important variables for coffee cultivation in agroforestry systems (AFSs). There is an appreciation of the ecological ...interactions between agricultural crops and native plants in the AFS.
Coffea arabica
L. is a shrub with geographic origins in the tropical forests of Africa. Thus, the production of coffee in AFSs can be an interesting alternative. In this study, we present the sensory and chemical profile of coffee grown in three AFSs in the Maciço do Baturité region, Ceará, Brazil and submitted to five types of post-harvest processing. This region has been producing arabica coffee for more than 200 years under forest conditions similar to the ecological characteristics of the geographical center of coffee with shadows produced by native plant species. The coffee fruits were obtained from an AFS with coffee cultivated in the natural/wild system, an AFS in conversion to syntropic, and a conventional AFS. The syntropic AFS and the natural/wild AFS had the highest sensory scores. With the exception of conven
t
ional AFS, spontaneous fermentations in covered terrain had higher total scores than fermentations carried out in sealed polyethylene containers. In the sensory panel, the body attribute contributed to the sensory discrimination of fermentation processes by wet and dry methods. Lipids, caffeine, carboxylic acids, and chlorogenic acids were responsible for the chemical differentiation of AFSs Therefore, AFSs and fermentation processes influence the chemical and sensory quality of coffee beans.
VOLATILE PROFILE OF Coffea arabica AND Coffea canephora var. conilon BY SHS-GC-MS AND CHEMOMETRICS. The volatile composition of coffee exerts a substantial influence on its quality, as it defines the ...characteristics of the beverage. However, these compounds are influenced by factors within the coffee production chain, such as botanical origin, geography, processing methods, and roasting. Consequently, the identification of such compounds becomes a vital tool for characterizing coffees to these factors. In this context, gas chromatography with headspace extraction is widely used for aroma analysis, providing a composition closer to consumer perception. Headspace extraction offers speed, simplicity, minimal sample preparation, and no need for solvents. In this study, static headspace extraction (SHS) coupled with gas chromatography-mass spectrometry (SHS-GC-MS) was employed to establish the chemical profile of volatile compounds in Coffea arabica and Coffea canephora var. conilon and determine discriminants between the species. A total of 97 compounds, belonging to 17 chemical classes, were identified. The chemometric analysis highlighted furans, phenols, and carboxylic acids as key differentiating classes. Notably, furfuryl alcohol, acetic acid, 4-vinylguaiacol, N-acetyl-4(H)-pyridine, and N-furfurylpyrrole emerged as crucial volatile compounds. The variable selection using Fisher weight applied directly in the chromatograms, produced models consistent with relative area data, with furfuryl alcohol and 4-vinylguaiacol regions being particularly influential in differentiation.
