New Delhi, Mar 27: You're about to eat your mid-work chocolate snack and then you see a white, powdery or streaky substance on the surface of your afternoon delight. What is this stuff? Firstly, this doesn't necessarily mean the chocolate is old, or inedible. This white 'thing' on the chocolate does not mean that the chocolate is mouldy. It means the chocolate has suffered from something called the "bloom".

There are two kinds of chocolate bloom: fat bloom and sugar bloom.

Sugar bloom occurs when moisture comes in contact with the chocolate. The chocolate that you eat typically contains sugar. Fat bloom is more complicated and may be caused by a combination of factors. These include improper storage conditions, changes in temperature, or poor tempering.

In fact, this strange phenomenon, known as "fat bloom", is all down to how we store our favourite chocolatey treats. It happens to be the biggest cause of customer complaints and costs the chocolate industry millions of pounds every year. So, what can you do to prevent it?

To properly store your chocolate, an ideal situation is to keep it in an airtight container in a cool, dry place, such as a cellar or pantry. If you live in a hot, humid area and you don't happen to have air-conditioning at your place, store it in the coolest place in the house, typically a lower cupboard or a dark pantry.

You can carefully wrap and seal your chocolates in a couple of layers of plastic wrap or ziplock bags to keep moisture and odors out. Lastly, you can also seal the bags in an airtight container, and then place it in the warmest spot in your refrigerator, often the top and middle shelves, toward the front.