Effect of roasting conditions on the quality of Robusta coffee beans (Coffea canephora)

Abstract

Robusta coffee, a specialty in Buon Me Thuot, Dak Lak province, contains many important bioactive compounds that benefit human health. Research on the selection of appropriate roasting conditions to create Robusta coffee products of good quality: Maintain the content of antioxidants such as total polyphenols (TPC), flavonoids (TFC) inherent in raw materials at a high level; lipid components and total acids, caffeine are maintained at a balanced level to create products with good color and sensory values during roasting at different temperatures and times. In this study, coffee beans were roasted at 230 and 240^oC at 15, 17, 19 and 21 minute intervals. The quality of coffee beans roasted at 240^oC for a period of 17 minutes is best, the beans with low moisture content (1.55 ± 0.04%) meet TCVN 7035:2002, the lipid content (12.50 ± 0.35%CK), the caffeine content (25.98 ± 0.48 mg CE/gCK) and total acid (0.50 ± 0.02%CK) are moderate, the total polyphenol content (18.64 ± 0.65 mg GAE/gCK) and the total flavonoids (5.26 ± 0.13 mg QE/gCK) are maintained at a high level, indicates that the color value (L*, a *, b*), brownization index (BI) was maintained at a stable level with values of 40.58 ± 1.01; 5.49 ± 0.25; 1.46 ± 0.42; 12.55 ± 1.07 respectively and produced a product with good sensory value, harmony in color, smell and taste (≥ 4.6 points on a scale of 0 to 5).