The activity and stability of α-amylase after high pressure homogenization were investigated. The enzyme buffer solution was processed at homogenization pressures up to 1500 bar. No changes in the enzymatic activity at 15, 45 and 75°C were observed after the homogenization process. The evaluation of calcium requirement to preserve the α-amylase stability during homogenization was carried out and the results indicated that the enzyme was stable even with no calcium available. The stability during storage (4 days), at pH from 4.0 to 6.7 and at a temperature from 15 to 75°C was also unaltered after homogenization. Additionally, the homogenization at elevated temperature (65°C) was not able to change the α-amylase activity. Therefore, it was concluded that this enzyme is resistant to the high pressure homogenization process. Industrial relevance: The application of α-amylase in juice processing is growing, mainly on juice from fruits with high starch content (i.e. banana and apple) and, also to prevent turbidity and viscosity enhancement caused by unripe fruit. 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