Chocolate is one of the most popular flavours the world over. Manufacturing chocolate or with chocolate as an ingredient presents its own challenges from an indoor air point of view. In this article, we take a look at a couple of those challenges and how HVAC systems can correct the manufacturing environment to create the optimum conditions for working with chocolate.
It is essential to maintain the correct relative humidity when manufacturing with chocolate. Chocolate absorbs moisture easily and this can lead to a multitude of issues, including the chocolate becoming too sticky, losing its shape or texture, acquiring unsightly spots on its surface etc. Furthermore, once spoiled by moisture, it is impossible to restore chocolate to its original condition.
Applying a chocolate coating by dipping by hand or mechanically enrobing, for example, requires the right humidity for the chocolate to set with a uniform distribution. 50% relative humidity is recommended for this particular process.
Controlling the humidity in other areas of the manufacturing facility, such as in the packaging room, is equally as important. If chocolate absorbs moisture, it can develop ‘sugar bloom’ – a patchy white discoloration on the surface of the chocolate.
The cooling coil in the air handling system (AHU) removes the humidity from the air. Condensed water from the air drains away and the dryer air then heats to the correct operating temperature.
For chocolate or chocolate coated products, temperature is very important. Even the slightest deviation in temperature can cause problems.
The melting point for chocolate is around 34°C, just below human body temperature. Temperatures higher than this could cause the chocolate to lose its shape, texture or taste.
Low temperatures, on the other hand, can cause condensation and surface spots to form on the product if transferred to a warmer place prior to packaging. It is therefore vital to maintain the correct temperatures throughout the production facility. Temperatures must also be consistent inside a particular production area – with no hot spots.
Optimal temperatures depend on the process, but for dipping or enrobing, a temperature of 24 – 27°C is recommended, and for storing chocolate, the temperature should be 16-18 °C.
The cooling and heating coils in the AHU are responsible for cooling or heating the air to maintain the right temperature. If the air is below the ‘set point’ temperature, the heating coil will increase the air temperature, and if above, the cooling coil will decrease it to bring it to the ‘set point’. For more information, click here.
Manufacturing in the right conditions will also help to maximise shelf-life.
There are a lot of dust challenges with chocolate. Cocoa, sugar and dried milk are all Atex rated products, which means they are potentially explosive under certain conditions. AHUs installed in areas with potentially explosive atmospheres have to comply with ATEX directive 2014/34/EU. It is also essential to keep all system explosion relief valves, explosion panels etc. maintained and checked.
Powdered ingredients can also be harmful to human health, as they can cause lung and skin irritations, which can lead to long-term health conditions. Manufacturers are obliged to comply with COSHH regulations to keep indoor air clean and safe for employees. Removing traces of the product from the air is therefore essential. There are a variety of dust control solutions. Local exhaust ventilation is one of the best ways to ensure clean air in your facility.
Find out more about how to prevent food factory powder explosions here.
Our air handling and dust extraction experts are here to help. If you have any questions, please get in touch on 01785 256976 or contact us here.