App note: Water activity in confectionery

In this whitepaper Novasina discuss how each candy present enormous challenges for all confectionery manufacturers but unfortunately are part of reality…

Candies – whether hard like a stone or sticking together in a clump, filled chocolates, milk chocolate with a texture like toffee – each present enormous challenges for all confectionery manufacturers but unfortunately are part of reality.

Of course there are many options in terms of product analysis to help control these issues, but not every measurement technology has the same effectiveness, accuracy and/or speed. A key element in the clumping or softening/hardening process is water, but more precisely it is the free water available in such products.

In terms of analytical technology, water activity is proven more effective, accurate and precise than moisture measurement. While moisture measurement delivers the total amount of water (and leaves you uncertain about the ratio of free to bound water), water activity provides the potential (not the amount) of the free water in a product. By knowing this potential, conclusions about stickiness or texture changes can be made. In most cases the help of so-called sorption isotherms is needed for a full understanding about the kinetics of water in sweets or other products.