Effect of the drying process on the volatile compounds and sensory quality of agglomerated instant coffee

The drying processing of agglomerated instant coffee can change the quality of the product due to the production of volatile compounds associated with the undesirable cereal aroma. Using fractional factorial planning, this study aimed to understand how the processing parameters (burner temperature, BT; steam pressure, SP; process air flow, AF; and fluidized hot bed section, LT) influenced the volatile profiles. The BT, AF, and the interaction of these variables (BT*AF) have significant influence (p < 0.10) on cereal aroma intensity. Results from the principal component analysis showed that 4,5-dimethylthiazole, 2-ethyl-3-methylpyrazine, and 4-ethyl-2-methoxyphenol are related to the undesirable cereal aroma.