Belt drying is a continuous convective drying process in which product travels on a perforated belt through staged zones of heated air, allowing large-volume, consistent output for vegetables, herbs and some fruits.
In trade practice
Temperature and airflow are set independently in each zone to balance moisture removal rate against colour retention and texture. Operators validate zone parameters during commissioning and record them in batch production logs reviewed by QA teams. A common process error is running the first zone at excessive temperature, which accelerates surface drying and increases the risk of case hardening, particularly in dense or high-sugar products.
In a specification
A dried-product specification referencing belt drying should state the maximum permitted inlet air temperature, target moisture content and water activity on exit, with tolerance limits.