Exploratory data analysis was used to evaluate the influence of NaCl concentration on the relation between endogenous microbiota (mesophilic aerobic bacteria, psychrotrophic bacteria, lactic acid bacteria, Enterobacteriaceae and Staphylococcus spp.) and biogenic amines (BAs) (histamine, tyramine, putrescine, cadaverine and spermidine) content in Brazilian dry-cured loin (BDL). Using hierarchical cluster analysis (HCA), initial data analysis led to samples separation into a higher and a lower NaCl cluster. The analysis of variance showed that the microbial counts did not differ between the clusters (p > 0.05). However, the higher NaCl cluster showed a lower level of BAs. Further, principal component analysis (PCA) demonstrated a negative correlation between the microbial counts and BAs content in the lower NaCl cluster, thus indicating the possibility of the higher BA's content in the lower NaCl cluster being a result of a stress-response mechanism. On the other hand, in the higher NaCl cluster, the salt concentration had an inhibitory property in BA's formation except for histamine. The collective results point to a NaCl threshold to minimise the production of BAs in BDL. The findings of the present exploratory study highlight the possibility of intervention for BA minimization without the need for designed starter cultures or preservation treatments.

Coffee quality is influenced by several factors, including the drying conditions. Therefore, this study evaluated the influence of the relative humidity of the drying air on the quality attributes of the coffee beverage. Arabica coffee (Coffea arabica L.) fruits were selectively harvested. The samples were dried in two steps in a fixed-bed dryer at an air speed of 0.33 ms-1. In the first step, drying was performed until the water content was 0.428 g of water g of dry matter-1, without controlling the dew point temperature. The second step was performed until the water content was 0.123 g of water/g of dry matter-1, with dew point temperature control. A total of 11 treatments were tested involving nine combinations of dry bulb temperatures of 35 and 40 °C and dew point temperatures of 2.6, 10.8, 16.2 °C, plus two dryings at 35 and 40 °C dry bulb temperature without dew point temperature control. The samples were evaluated sensorially by three certified specialty coffee tasters. The data were subjected to principal component analysis. In the sensory analysis, the samples received total scores of 83.0 to 85.5 points. The drying conditions significantly influenced the quality of the coffee beverage. Drying at a dry bulb temperature of 40 °C and a dew point temperature of 16.2 °C (25% RH) is indicated for the production of higher quality coffees with a shorter drying time.

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Changes in color of coffee grains are indications of occurrence of oxidative processes and biochemical changes, which can alter the taste and aroma precursors of the grains, resulting in lower beverage quality. Thus, the aim of this study was to evaluate the color characteristics of peeled coffee grains subjected to different relative humidity of the drying air after partial drying. Coffee (Coffea arabica) fruits were harvested in the cherry stage and were wet processed. The treatments were the results of the combination of three dry bulb temperatures and three dew point temperatures. The control of dew point temperature was performed only after the grains reach the partial drying. Considering the Tbd of 40 °C - 40 °C, the reduction of the Tpd (2.6 °C) increased the grains bleaching, while the increase of Tpd (16.2 °C) resulted in a more yellowish-red. Tbd of 40 °C - 35 °C and 35 °C - 35 °C are indicated for bluish-green color formation, associated with higher sensory quality. The Color Saturation (C*) of the coffee grains are highly correlated with the b* color parameter, while the tonality (Hue) is negatively correlated with the a* color parameter.

The mathematical modelling is fundamental for the understanding of the related processes the drying, that influences the quality of the coffee drink. The objective of this study was to evaluate the influence of different relative humidity of the drying air after partial drying on drying kinetics of peeled coffees. Coffee fruits were harvested in the cherry stage and processed by wet, resulting in the portion of peeled coffee. Eleven treatments of drying were accomplished, being nine results of the combination of three dry bulb temperatures and three dew point temperatures, more two treatments without the control of the dew point temperatures. The control of the relative humidity by the dew point temperature was made after the grains reached the partial drying. Among the studied models, those of Diffusion Approximation and Modified Midilli were the most adequate for describing the drying process of the first and second part of drying respectively. The effective diffusivity coefficient of water in coffee grains ranged from 0.81 x 10-11 to 1.84 x 10-11 m² .s-1 during the first part of the drying and ranged from 1.49 x 10-11 to 3.29 x 10-11 m² .s-1 during the second part of the drying, increasing significantly with the reduction of the dew point temperature and increase of the dry bulb temperature.