How to evaluate blanching efficiency?

Finally, let us learn how to evaluate blanching efficiency? Normally, two of the more heat resistant plant enzymes, namely peroxidase and catalase are used to evaluate blanching efficacy. If both these enzymes are inactivated, it can be safely assumed that most other enzymes are also destroyed. Remember, blanching  is a delicate processing step; time, temperature and the other conditions must be carefully monitored. Blanching time to inactivate enzymes are dependent on:

1.  Type of food

2.  Method or type of heating

3. Product size

4.  Temperature of heating medium

In case of steam blanching, the food product is directly exposed to steam in place of using water as a medium for blanching, which avoids the loss of food soluble solids (flavours, vitamins, acids, sugars etc.) to blanching medium as well  as solves the problem of disposing blanching medium after processing.