What’s That White Stuff on Your Chocolate Bar?
Something doesn’t look right.
The expiration date on that glorious chocolate bar says that it’s still going to be a long time before you will need to sadly throw it away. However, you can’t help but notice that suspicious white surface that has formed on top of the chocolate…
Instead of having a shiny and inviting appearance, the chocolate looks like a layer of mould or dust was spread on it. It doesn’t seem appealing and you are still confused: if the chocolate hasn’t expired, why does it look so bad already?
The chocolate didn’t go bad. In fact, it takes an exceptionally long time for chocolate to expire. You have 6-8 months to consume milk and white chocolate after you open it, and even one year if the chocolate is still unopened and in its original wrapper. When it comes to dark chocolate, the real expiration time gets postponed even more: you can keep dark chocolate in your house for up to ten years, and it will still be safe to eat.
Some chocolate professionals claim that dark chocolate is best eaten fresh, while others believe that dark chocolate becomes better as time goes by. Like wine, some new flavours might develop in the chocolate bar with ageing. If you are an attentive chocoholic, you might notice that dark chocolate bars usually don’t carry “Expiration” dates, but “Best Before” dates (*).
This is because dark chocolate might be best enjoyed within one year from its production date, to experience the best flavours and textures, but it remains edible for well beyond that time.
The reason why chocolate lasts more than other foods is that there is no water activity in it, which means that there is no environment for bacterial growth. Also the cocoa butter has a stabilising effect on the chocolate.
So what’s that white stuff you’re looking at?
Your chocolate can develop a white surface for two distinctive reasons: humidity (Sugar Bloom) or bad tempering/temperature fluctuations (Fat Bloom).
Sugar Bloom & humidity
Sugar bloom happens when water comes into contact with the chocolate. If the chocolate was placed in the fridge or it has spent some time in a place with a high humidity level, sugar bloom will most likely occur.
The white stuff you see on the surface is condensation: the chocolate absorbs the water, causing the sugar to dissolve, and when the water evaporates, the sugar re-solidifies in small crystals, causing a layer of dried sugar to appear on the surface. To say it professionally, the sugar has crystallised.
Fat Bloom & temperature
Fat bloom has to do with cocoa butter instead (the fatty part of chocolate). To be stable and keep its place inside the chocolate bar, the cocoa butter needs to be in a specific crystal structure called “Phase V” or “Form V” (*).
As chocolate consumers, we don’t need to learn what this Phase or Form V is and all the complicated chemistry behind it. We just need to know that it’s achieved through tempering: a process where the temperature of melted chocolate is slowly raised and lowered alternatively while constantly stirring. This crucial step in the bean-to-bar making gives the chocolate its typical shiny appearance, smooth texture and good snap when you break it.
This said, fat bloom occurs when the cocoa butter loses this magical structure because it was either tempered badly (or not tempered at all), or it was exposed to warm temperatures: the cocoa butter melts, separates from the other ingredients and rises to the surface.
So is my chocolate safe to eat?
You now understand that, whether it’s sugar or fat bloom, the chocolate hasn’t gone bad. It has just changed its internal ideal structure, with the sugar or the cocoa butter that stopped being in their designated positions and got all over the place.
Sugar and fat bloom are easily recognisable just by looking attentively at that white stuff: sugar bloom will look like a uniform, white, dusty and grainy coating, while fat bloom will take the form of whitish/greyish streaks or spots on the surface.
Although chocolate affected by sugar or fat bloom is still safe to consume, it might not be best for savouring, since it has lost its original consistency and taste: texture will result chalky and crumbly, with the chocolate breaking into pieces before it even starts melting, and flavours will be negatively affected as well.
If you are still doubtful, you can conduct some sensorial tests to see if the chocolate has actually gone bad or not. Sniffing the chocolate is the first step: if the nose smells something funky that induces cringing expressions, the chocolate might have actually gone bad.
A taste test will cast aside any doubt: any rancid and off flavours are indicators that the chocolate should be discarded. If the white appearance of your chocolate stops you from eating it, you can still use it for cooking and baking exceptional chocolate creations.
How to avoid sugar or fat blooms
To avoid sugar and fat bloom, it’s good practice to always store your chocolate in a dark (far away from any light source), cool (not warm and not cold) and dry places like the pantry or a drawer. This way the chocolate won’t suffer any change in temperature.
If fat bloom still occurs despite your good care, something wrong must have happened at the factory during the tempering process.
Now that you know what that white stuff on your chocolate is, you don’t need to get discouraged when you see it. The chocolate is most likely still safe to eat, and it’s up to you whether you want to savour it or use it for delicious chocolate desserts and decadent hot chocolates.
Join our chocolate newsletter for news, discounts and more!