Thousands of years ago, an ancient civilisation, in what is now known as Ecuador, was the first to recognise and revere the cocoa tree as a sacred source of food. Chocolate comes from cocoa beans - which actually don’t taste anything like the chocolate we know and have a bland taste in their raw form. It is only when the cocoa beans go through the process of fermentation and roasting that the familiar cocoa flavour develops. 

Chocolate is used worldwide in many shapes and forms, in both sweet and savoury dishes, and the husk of the cocoa tree is also used to make tea, which is said to replenish with energy and boosts the mind. When it comes to a chocolate bar, the mouthfeel, as well as how it looks, sounds when you break it, and smells, are of utmost importance. A good chocolate should “snap” when you break it, and the chocolate should be shiny with a rich deep colour. 

Chocolate never ceases to amaze and indulge the world over, being probably the most loved and widely available confectionery around. So, it is a most disappointing experience to open a chocolate bar to find it has fuzzy-white layer or spots. This phenomenon is called “blooming” or “fat bloom”. To start off, fat bloom in chocolate is definitely not mould, and it’s not a health hazard, so a chocolate with fat bloom is still good to eat - having said that it is definitely not something that you look forward to when unwrapping a nice bar of chocolate. 

So why does fat bloom occur? 

Fat bloom in chocolate is caused by uncontrollable crystallisation of the fat in the chocolate. Whilst crystallisation of fat is a natural occurrence, when then is no control over the number, size and orientation of the crystals, fat bloom is observed. In short, the physical crystalline phase of the fat molecules is not what gives you a snappy, shiny chocolate bar. One thing to note is this is not a chemical phenomenon, that is none of molecules in the chocolate are broken down and there is no chemical reaction taking place. 

A fun fact is that if you were to take the bloomed chocolate, melt it and temper it again, thus controlling crystallisation of the fat, to form a chocolate bar, it will become shiny and snappy once again.

So, what can be done to resolve the issue of fat blooming in chocolate, you might ask. The good news is that something can be done to greatly reduce the chances of fat bloom in chocolate occurring.

First and foremost, chocolate manufacturers should understand the root cause of fat bloom as in most cases, fat blooming issues can be resolved via formulation and/or process, depending on the case. When tackling formulation issues, one needs to understand the client’s needs as well as the current interaction of the formulation at a chemical and physical level, to see whether any changes in formulation are needed. Many of you might think that changing the formulation of the product will definitely change the taste of the product. Whilst in some cases this might be true, this is not necessarily the case if the right changes are implemented. Some alternative formulations are extremely close in terms of flavour and texture, and so there would be a minimal to no impact to the end product.

Process is also another important factor to look at when tackling the issue of fat blooming. Changing or tweaking the manufacturing process can make a huge difference. In most cases this would not necessarily mean needing additional equipment or adding extra manufacturing costs. Sometimes it’s the small tweaks that make a big difference. To determine the root cause the entire process needs to be kept in mind; from manufacturing processes to storage, all can affect the chance of fat bloom developing in chocolate. 

Other than fat bloom, chocolate can experience sugar bloom, which is when the chocolate is in a high humidity environment - this however happens when the chocolate is packed at high humidity levels, so it is much more easily controlled. What happen in such circumstances is that if you were to pack a product in high humidity levels, the humidity gets trapped inside the packaging, which then, due to temperature fluctuations in the supply chain, would condense inside the packaging, with the water dissolving the sugar, to then form sugar crystals once the temperature increases again and the water re-evaporates. This type of bloom is a rare phenomenon.

So, if you open a chocolate bar with a white fuzzy layer, it’s highly likely to be fat bloom. It is not a health hazard so eat to your heart’s content. Having said that it would be nice if your chocolate bar is shiny and snappy every time you unwrap it.