Water Activity - A Reference
Every water activity value I've measured for a filling, gathered in one place and linked to its recipe.
- values
- 65
- recipes
- 32
- range
- 0.2372 – 0.8311
Updated Sep 20, 2026
Where the 65 land
65 values - 0.2 to 0.9 - dashed lines are thresholds
The dashed lines are thresholds from food microbiology: below 0.60, practically nothing grows. S. aureus (golden staph) does not grow at 0.85 or below.
All values
65 of 65 values
24 of 65 values
12 published fillings have no value. That means I haven't analyzed them - not that I've estimated their value. I don't publish a value that doesn't come straight from the aw meter.
By kind of filling
I only write down what the aw meter says
Every value comes from one analysis on my own AquaLab 4TEV Duo at 20 °C. No numbers are borrowed from a book. If I didn't measure the filling, it isn't counted here.
A value is a fact about one batch
Your cream, your fruit purée and your kitchen will give you a filling somewhere near these values - not exactly the same. Use the table to see what a filling usually gives, and measure for yourself (when it matters) before you decide on shelf life. The thresholds 0.60 and 0.85 are common practice in food microbiology, not promises. A low aw value slows down spoilage, but it doesn't excuse poor hygiene or a badly sealed bonbon.
Cite it, download it all
Rajala, M. (2026). Water Activity Reference: measured aw of bonbon fillings. matsrajala.com/en/the-lab/water-activity-reference. Retrieved ….
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