Invertase improves shelf life by changing
the water activity of confections. Since invert sugar has a lower water
activity than sucrose at the same solids level most microorganisms can
not grow. (Invert sugar has a solids level greater than 75% compared to
a maximum of 67% for liquid sugar.) The calculated water activity for
sugar approaches 0.65 compared to only 0.85 for liquid sugar. These
are responsible for giving the antimicrobial characteristics to fondant
fillings and other confections made using invertase.
Invert sugar has a very high affinity
water. Therefore, invert sugar can be used to reduce crystallization
keep products moist to extend shelf life.