Pulse blanching is a brief heat treatment applied to pulses before freezing, canning or drying that inactivates spoilage enzymes, reduces surface microbial load and stabilises colour and flavour during subsequent storage.
In trade practice
Processors validate blanching by testing for residual peroxidase or catalase activity, since complete enzyme inactivation is the accepted indicator of adequate treatment. Time and temperature combinations vary by pulse type and size; under-blanching leaves active enzymes that cause off-flavours, while over-blanching softens texture and leaches soluble solids. Buyers should request blanching validation records as part of the production dossier, particularly for frozen or retorted pulse products. Third-party auditors check that validation is repeated whenever line parameters change.
In a specification
A purchase specification for frozen or canned pulses should state that blanching must be validated by a recognised enzyme-inactivation test, with records available on request.