Deep drying flour / starch
By deep drying flour or starch we mean drying further than what is required to obtain a product with a stable shelf life. By removing more water and making a very dry product, the cell structure changes and with that the product’s functionality. this opens a new range of possibilities and applications.
The process to deep dry requires accurately applied heat input to evacuate the captured water from the cell structure but to not overheat the product. As a result, due to the changed cell structure, the process is irreversible. The final product dissolves easier in cold water. Applications are for example instant soups and sauces.
Similar to flour drying can starch be deep dried too. Both processes are quite similar. The heat treatment of flour does not involve any prior chemical or enzymatic modification. Modification prior to deep drying is common for starch.
Apart from that, deep drying of chemically modified starch is the first thermal step in the dextrinisation process. Read further about the dextrinisation process on our web page Dextrin.
Most flours and starches are called semi-perishable products. Yet
they still require drying to preserve them. By drying the products,
the amount of ‘free’ water present in the cell is reduced to a point
which will inhibit the growth of the organisms such as bacteria,
yeasts, and moulds. In the case of starches and flours, that point
is around 11-13% of final moisture in the product. Few products
like potato starch permit a higher residual moisture to become
stable for storage.