High pressure homogenization of a fungi α-amylase

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 relevanceThe 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. The HPH is a promising non thermal methodology applied to stabilize juices microbiologically and physically, through particle size reduction and the high stability of α-amylase during HPH process can be important to guarantee the effectiveness of α-amylase during and after HPH.

► The high pressure homogenization caused no changes in the α-amylase activity.
► The α-amylase stability was also unaltered by a homogenization up to 1500 bar.
► Associated heat and homogenization was not able to modify the α-amylase activity.
► The α-amylase is resistant to high pressure homogenization.