Three casein hydrolysates (degree of hydrolysis (DH) of 23, 47, and 65.5 (%)) were debittered using three different hydrophobic adsorption columns, C18, C8, and phenolic resin (PR). Higher DH hydrolysates resulted in higher total nitrogen yields through the debittering process. The C18 and PR columns had more effective debittering than the C8 column, which had the highest processing yield. The PR column had much lower processing yield than the C18 column. Q-value correlated with bitterness in the hydrolysates. Antigenicity of treated hydrolysates was reduced by the debittering process.