If you have ever forgotten about a piece of chocolate in your car, your cupboard, or your coat pocket, you may have seen a white coloring appear on the surface of the chocolate.
You are probably wondering what this means, and if the chocolate is still safe to eat. I was wondering about this myself, so I did some digging to find out what causes this problem.
So, why does your chocolate look white? Your chocolate looks white due to chocolate bloom, which causes whitish-gray swirls or crystals on the surface of the chocolate. There are two types of chocolate bloom: sugar bloom (caused by damp storage conditions) and fat bloom (caused by warm temperatures that cause cocoa butter to melt).
Let’s take a closer look at why your chocolate is turning white, and what causes it to happen. Then, we’ll get into ways to prevent chocolate bloom from happening in the first place. We’ll also offer some suggestions about what to do with chocolate that has turned white due to chocolate bloom.
Why Does My Chocolate Look White?
As mentioned above, your chocolate looks white due to chocolate bloom, which can affect both appearance and texture of chocolate. The most obvious sign of chocolate bloom is the appearance of whitish-gray swirls (fat) or crystals (sugar) on the surface of the chocolate.
The two major types of chocolate bloom are sugar bloom and fat bloom. Both of these types of chocolate bloom have different causes, and both affect the appearance and texture of chocolate in different ways.
Chocolate bloom may even affect the taste of chocolate, although the chocolate may not really be spoiled. The ingredients are still there, just in a less uniform pattern.
It’s time to take a closer look at the first type of chocolate bloom: sugar bloom.
Sugar Bloom on Chocolate
According to Michigan State University, “With sugar bloom the chocolate is spotted with white, it feels dry and does not melt when touched.”
Sugar bloom occurs when chocolate is stored in a damp or humid place, such as in a refrigerator or the glove compartment of a car on a humid day. Chocolate that is not wrapped in paper and foil or kept in a sealed container is more likely to suffer from sugar bloom.
So how exactly does sugar bloom happen on chocolate?
First, the dampness (humidity) in the air causes moisture to collect on the surface of the chocolate, due to condensation. (Note: the same thing, condensation, causes morning dew to appear on grass in the summer, since the cool night air can hold less water than warm daytime air).
Then, when the condensation and sugar meet, the water dissolves the sugar and draws it out of the chocolate mixture.
Finally, the moisture evaporates back into the air, leaving white sugar crystals on the surface of the chocolate (causing the appearance of the characteristic “white spots” due to sugar bloom).
These sugar crystals cause the surface of the chocolate to take on a rough and grainy texture. Chocolate with sugar bloom feels dry to the touch because the moisture has evaporated away.
Of course, sugar bloom is not the only type of chocolate bloom that can change the appearance and texture of chocolate. Now let’s take a moment to talk about fat bloom.
Fat Bloom on Chocolate
According to Michigan State University, “Fat bloom tends to be streaked with white or gray, feels slick and melts.”
Fat bloom occurs when chocolate is stored in a place where it gets too warm, such as in a cabinet near a hot stove, in a warm truck during shipping, or in your pants pocket.
So how exactly does fat bloom happen on chocolate? One theory to explain fat bloom on chocolate is the “phase separation” theory.
First, the chocolate is exposed to a temperature that is too warm – this will depend on the type of chocolate, but generally a temperature of more than 70 to 75 degrees Fahrenheit (21 to 24 degrees Celsius) will cause chocolate bloom.
At these higher temperatures, some parts of the cocoa butter in chocolate starts to melt. When the cocoa butter melts, it expands, and some of it gets squeezed out through pores in the chocolate and becomes separated from the chocolate mixture.
When temperatures cool enough for the fat to become solid again, the cocoa butter crystallizes on the surface of the chocolate. This is what causes the characteristic white or gray swirls on the surface of the chocolate.
Chocolate with fat bloom on the surface feels slick because fat, such as cocoa butter, feels slippery (think about the oil used to lubricate your car’s moving parts).
For more information on the phase separation theory of fat bloom, check out this article on chocolate bloom from Wikipedia.
Keep in mind that fat bloom and sugar bloom can occur at the same time – this is most likely during hot and humid conditions, such as the “dog days” of summer. Be careful if you order chocolate during the hotter months – if it is not properly shipped, your chocolate can bloom quickly!
Also remember that chocolate that is filled with caramel or nougat tends to bloom more quickly than other chocolate, although it is unclear why this happens.
Why Does Chocolate Turn White in the Refrigerator?
Many people come up with the idea of putting chocolate in the refrigerator to preserve it – after all, it works for other foods, so why not chocolate?
It even makes sense that this practice would prevent fat bloom, since a refrigerator would prevent the high temperatures necessary for cocoa butter to melt and separate from chocolate.
However, sugar bloom can still occur when chocolate is stored in a refrigerator. As mentioned above, high humidity will often lead to sugar bloom. The inside of a refrigerator is often damp enough to cause sugar bloom on your chocolate, so avoid storing your chocolate in the fridge.
How to Prevent Chocolate Bloom
Now that we know why your chocolate is white (chocolate bloom) and what causes it (sugar bloom or fat bloom), we can take some steps to prevent chocolate bloom from happening in the first place.
Here are some tips for preventing sugar bloom and fat bloom on your chocolate.
- Keep your chocolate out of the refrigerator! Instead, put your chocolate in a cool, dark place in your house, out of sunlight and away from the kitchen stove or any heating vents. If your basement is not too damp, it will probably stay cool enough to prevent fat bloom and dry enough to prevent sugar bloom. The ideal temperature for storing chocolate is 57 to 64 degrees Fahrenheit (14 to 18 degrees Celsius).
- Don’t leave your chocolate in the car! If you are buying chocolate for yourself or for a special occasion (birthday, holiday, etc.), then plan your trip so that buying chocolate is the last task. That way, it won’t sit in the car for too long, which can cause bloom quickly on hot, humid days.
- Seal your chocolate properly! Keep chocolate in the foil and paper wrapping that it comes in, to maintain a moisture barrier between the chocolate and the air. You can also put your chocolate in an airtight container, such as a Tupperware, to seal it off from any changes in humidity in the air in your house.
- Temper your chocolate correctly!. This will minimize pores and prevent fat bloom. The proper temperature for tempering depends on the type of chocolate. Remember that there is no need to temper compound chocolate. For more information, check out my article on compound chocolate.
- Keep track of your chocolate! Eat it before it gets a chance to bloom. Don’t buy more until you finish what you have. This will avoid chocolate getting lost in the back of the cupboard and sitting through changes in temperature and humidity that make chocolate bloom more likely.
How Long Does It Take For Chocolate To Turn White?
If chocolate is exposed to high temperatures or high humidity, then chocolate bloom can occur in a short time period (within hours or days).
In general, the time it takes for chocolate to bloom is not set in stone. If stored properly, chocolate can last a long time (many months) without any chocolate bloom or decrease in quality.
There are a few things to keep in mind when it comes to storing chocolate:
- White chocolate goes rancid (meaning that the fat content becomes spoiled) more quickly than chocolate with cocoa solids in it. This is due to the fact that chocolate with cocoa solids contains flavanols, which act as a natural preservative. (Darker chocolate contains more of these flavanols).
- High sugar content also acts to preserve chocolate and prevents it from spoiling. This is why milk chocolate can last a long time, even though it has less flavanols than dark chocolate.
- Compound chocolate also lasts a long time, due to the fact that vegetable oil and other additives can inhibit fat bloom. Compound chocolate also has little or no cocoa butter, which is a more temperamental fat than vegetable oil.
Why Does Chocolate Turn White after Melting?
Chocolate turns white after melting if it is not tempered properly. Basically, the chocolate is crystallizing in a non-uniform way (the cocoa solids and cocoa butter are separated and are no longer blended properly).
How to Fix Chocolate That Has Turned White (How to Fix Chocolate Bloom)
Chocolate that has bloomed due to high storage temperature, high humidity, or improper tempering may not look very appetizing. However, bloomed chocolate can still be salvaged in a variety of ways.
To save chocolate that has turned white, you can:
- Melt the chocolate and give it a second chance by shaping it into bars or candy. This works best if you use specially designed chocolate molds.
- Use the chocolate for making cakes, cupcakes, cookies, or other baked goods. Remember: if the recipe calls for unsweetened chocolate, be sure to adjust the recipe, or else your creation will end up too sweet!
- Melt the chocolate and use it to make candy or treats, such as chocolate-covered nuts or fruit, or a chocolate filling or frosting (ganache) for pastries.
- Heat up some milk and add the bloomed chocolate to make hot cocoa. This is my favorite way to use up chocolate in the winter!
By now, you have a much better idea of why your chocolate looks white, and what causes this problem to occur. You also know how to prevent it in the future, and what to do with chocolate that has already suffered this fate.
I hope you found this article helpful – if so, please share it with someone who can use the information.