High pressure homogenization of a fungi α-amylase

The activity and stability of alpha-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 degrees C were observed after the homogenization process. The evaluation of calcium requirement to preserve the et-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 degrees C was also unaltered after homogenization. Additionally, the homogenization at elevated temperature (65 degrees C) was not able to change the alpha-amylase activity. Therefore, it was concluded that this enzyme is resistant to the high pressure homogenization process. Industrial relevance: The application of alpha-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 alpha-amylase during HPH process can be important to guarantee the effectiveness of alpha-amylase during and after HPH. (C) 2011 Elsevier Ltd. All rights reserved.