Understanding the science behind chocolate bloom
Chocolate bloom is a common and fascinating occurrence that can affect any type of chocolate, including the shell-coated kind like M&Ms. There are two primary types of bloom, each caused by different environmental factors: fat bloom and sugar bloom. Understanding the difference is the first step toward preventing those pesky spots.
The chemistry of fat bloom
Fat bloom is the more common type of bloom and occurs when the chocolate's fat content, primarily cocoa butter, separates and rises to the surface. This happens due to temperature fluctuations, even minor ones, that are common during transport or storage. As the temperature warms, the cocoa butter melts and migrates through the porous structure of the chocolate. When it cools and re-solidifies, it crystallizes on the surface, creating a hazy, streaky, or gray finish that looks like white spots. Poor tempering during the manufacturing process can also contribute to fat bloom, as improperly formed cocoa butter crystals are less stable. This is why even a brand-new package might show signs of spotting.
The anatomy of sugar bloom
Sugar bloom is caused by moisture and can create a similar white, speckled appearance on the chocolate's surface. When chocolate is exposed to moisture, for instance, from being stored in a humid environment or transferred from a cold refrigerator to a warmer room, condensation forms on the candy. This moisture dissolves the sugar in the candy shell, and as the water evaporates, it leaves behind coarse, irregular sugar crystals on the surface. This gives the candy a rough, grainy, or dusty texture, unlike the smoother, more waxy feel of fat bloom.
Is it safe to eat M&Ms with spots?
This is a question many people have when they find a bag of spotted M&Ms. The short answer is yes, they are completely safe to eat. Chocolate bloom is a cosmetic issue, not a sign of spoilage or mold. The flavor and texture, however, may be compromised. Fat bloom can result in a soft, less pleasant mouthfeel, while sugar bloom will create a gritty or dry texture. The candy is still perfectly edible, though it may not be as enjoyable as a fresh, shiny M&M.
How to prevent chocolate bloom
The key to preventing both fat and sugar bloom is to control the storage conditions. Proper storage ensures your chocolate remains in peak condition until you're ready to enjoy it.
- Maintain a consistent temperature: Store M&Ms and other chocolate in a cool, dry place with a stable temperature, ideally between 60–70°F (15–21°C). Avoid leaving them in a hot car, near a window with direct sunlight, or in a warm cupboard near the stove. Temperature fluctuations are the primary driver of fat bloom.
- Store in a dry environment: Humidity is the enemy of chocolate and the main culprit behind sugar bloom. Keep M&Ms in a dry place, away from sources of moisture like a refrigerator. If you must refrigerate them, place them in an airtight container to prevent condensation from forming on the surface when you take them out.
- Use airtight containers: Once a bag of M&Ms is opened, it's best to reseal it tightly or transfer the candies to an airtight container. This prevents moisture from getting in and also protects against absorbing other strong odors, as chocolate can absorb smells like a sponge.
- Consider a pantry, not the fridge: While putting chocolate in the fridge seems like a good idea, the colder temperature and higher humidity can actually cause sugar bloom when the candy is removed. A cool, dark pantry or cupboard is often the best storage location.
Fat Bloom vs. Sugar Bloom: A Comparison
| Feature | Fat Bloom | Sugar Bloom |
|---|---|---|
| Appearance | Hazy, streaky, or gray patches on the surface. | White, dusty, or spotty specks on the surface. |
| Cause | Temperature fluctuations cause cocoa butter to migrate and re-crystallize on the surface. | Moisture dissolves sugar crystals, which re-form as rougher crystals when the water evaporates. |
| Texture | Smooth, slick, or waxy to the touch; can feel softer or crumble more easily. | Rough, grainy, or sandy to the touch. |
| Test | Rubbing it with your finger makes it disappear and leaves an oily residue. | Rubbing it with your finger will not make the granules disappear. |
| Edibility | Safe to eat, though texture may be unappetizing. | Safe to eat, though texture may be unappetizing. |
What if my M&Ms have already bloomed?
If you've discovered a bag of spotted M&Ms, don't throw them out! Bloomed chocolate is still completely usable in many culinary applications. Melting the chocolate down for baking is the most common solution, as the process of heating and stirring will re-incorporate the fat and sugar crystals, restoring the chocolate's consistency.
Some ideas for using bloomed M&Ms:
- In cookies or brownies: The spotting will be completely unnoticeable once melted into a cookie or brownie batter. Just chop them up and add them to your recipe as usual.
- As a hot chocolate mix-in: Melt bloomed M&Ms into a mug of hot milk to create a rich, creamy hot chocolate.
- For chocolate sauce: You can melt down a bloomed batch of M&Ms to create a delicious chocolate sauce for ice cream or other desserts.
- In a trail mix: If the change in texture doesn't bother you, the candy is still fine to eat straight from the bag, especially when mixed with other ingredients in a trail mix.
Conclusion In conclusion, the spots on your M&Ms are a normal, non-harmful sign of chocolate bloom, caused by temperature fluctuations (fat bloom) or exposure to moisture (sugar bloom). While the aesthetic and texture may be less than perfect, the candy is still perfectly safe to consume. By storing your chocolates in a consistently cool, dry place and using an airtight container, you can help prevent bloom and enjoy your M&Ms as the shiny, smooth treats they were meant to be. However, if bloom does occur, you can still put the candies to good use by melting them down for baking or desserts, ensuring no chocolate goes to waste.
How to Store Chocolate Safely
- Store in a cool, dark, and dry place: This is the golden rule for chocolate storage. A pantry, cellar, or cupboard away from heat sources is ideal.
- Keep away from strong odors: Chocolate readily absorbs odors from its surroundings, so keep it sealed and away from spices or pungent foods.
- Use an airtight container for open packages: This is especially important for candies like M&Ms to prevent moisture and condensation exposure.
- Avoid the refrigerator (if possible): Refrigerators are high-humidity environments that can accelerate sugar bloom. If you must refrigerate, place the candy in a sealed container and let it come to room temperature slowly before opening to prevent condensation.
- Check the 'Best Before' date: While bloom doesn't indicate spoilage, it's always good to enjoy your chocolate within its freshness window for the best taste and texture.
What to Do with Bloomed Chocolate
- Melt it for baking: Use the bloomed M&Ms in recipes that call for melted chocolate, such as cookies, brownies, or cakes.
- Create a hot chocolate mix: Melt the candy into warm milk for a quick and delicious hot chocolate.
- Make chocolate sauce or fondue: The bloomed chocolate will melt down perfectly to make a smooth sauce or dip for fruits and desserts.
- Add to trail mix: The change in texture is less noticeable when combined with other ingredients like nuts and dried fruit.
- Consider it a flavor experiment: Some people find the texture change to be a mild and unbothersome quirk of a well-aged chocolate snack.
