POTENTIAL OF COFFEA CANEPHORA FOR COLD BREW PRODUCTION: PHYSICOCHEMICAL AND BIOACTIVE COMPOUND CHARACTERIZATION

Brazil is the world's largest producer and exporter of coffee, with Coffea arabica and Coffea canephora being the main species cultivated. The state of Espírito Santo stands as the primary national producer of Conilon coffee (Coffea canephora), a species recognized for its high concentration of phenolic compounds, particularly chlorogenic acids, which are widely associated with antioxidant properties and human health benefits. The intrinsic chemical composition of the beans, degree of roasting, and extraction conditions directly modulate the chemical profile and overall sensory quality of the final beverage. Among the various preparation methods, cold brew, obtained by extracting coffee ground matrices in cold water over extended periods, has gained prominence due to its distinctive sensory characteristics. This study aimed to produce and characterize cold brew beverages formulated with blends of fermented Coffea canephora, incorporating varying proportions of green and roasted beans. The beverages were prepared using roasted-to-green coffee mass ratios (w/w) of 100:0 (F100), 75:25 (F75), and 50:50 (F50), employing 6 g of coffee per 100 mL of mineral water. Extractions were performed in triplicate for 12 and 24 hours. The parameters evaluated included pH, total soluble solids (TSS), titratable acidity (TA), colorimetry, total phenolic content (TPC), and antioxidant capacity measured via FRAP and ABTS assays. The resulting data were subjected to analysis of variance (ANOVA) and Tukey's post-hoc test (p<0.05). Phenolic content was significantly affected by the roasted-to-green ratio, yielding higher concentration values in F100 (1332.77 mg GAE/L) than in F50 (868.00 mg GAE/L). Greater efficiency in the extraction of phenolic compounds was observed in roasted matrices, attributed to microstructural alterations induced by the thermal process of roasting that enhance mass transfer kinetics during aqueous extraction. TSS values were significantly influenced by both extraction time and roasted-to-green ratio, with higher values recorded in beverages extracted for 24 hours (1.43%) compared to those extracted for 12 hours (1.31%). Formulations F100 and F75 exhibited no statistically significant differences regarding TSS. The pH was significantly impacted by extraction time, roasted-to-green ratio, and the interaction between these factors, ranging from 5.62 to 5.83. Regarding TA, only the roasted-to-green ratio demonstrated a significant effect, with F100 exhibiting the highest values (0.064%). Neither the roasted-to-green ratio nor the extraction time significantly altered antioxidant capacity (p>0.05), with mean values of ABTS at 10.94 µmol/mL and FRAP at 24.98 mmol/L. The colorimetric parameters L* and a* were significantly influenced by the roasted-to-green ratio (p<0.05), whereas b* displayed no significant variation. The findings demonstrate that the proportion of green to roasted beans predominantly affected the physicochemical attributes of cold brew beverages, contributing valuable insights toward process standardization and the development of coffee beverages with superior quality and technological potential.

Acknowledgments: CAPES; CNPq; FAPES (#763/2024; #680/2024).