There are certain flavors and smells we can almost always associate with a specific Holiday, but few are more timeless and classic than the taste and scent of freshly baked Gingerbread. From gingerbread cookies and cakes to the family traditions of building colorful gingerbread houses bound together with icing and gum drops, it just wouldn’t be the Holiday season without it…and it wouldn’t be gingerbread without a key ingredient – molasses. An ingredient that takes both reliable compressed air and vacuum solutions to produce.
Well before this this thick honey-like syrup makes its way into any batter, the base ingredient – either sugar cane or beet root - must first go through a long extraction and refining process. Let’s look at how this is done:
Washing and Cutting
To begin, sugar cane must first be cut and loaded onto pneumatically powered conveyors that use air compressors like the Atlas Copco ZR 160 VSD+to transport them to be cleaned with hot water sprays. This will ensure that any dirt and debris from the field have been removed. Once they have been thoroughly washed, the cleaned cane pass through a cutting machine that cuts them into short pieces or shreds.
If beets are being used, beet roots go through a similar process of cleaning and removing any debris from the field. After being pumped through the large washer, the beets move though a slicer which cuts them into strips called cossettes.
Extraction of the Sugar Juice
After being cleaned and cut to the exact specifications of the manufacturer, the cane or beets are brought to the processing plant where the sugar juice extraction process can begin. For sugar cane, there are two different ways this is accomplished. Either though diffusion or milling. With the diffusion method, stalks are dissolved in hot water or lime juice while the milling process requires heavy rollers to extract the juice under pressure.
In a sugar beet factory, the freshly sliced beet roots, or cossettes, are loaded into cylindrical diffusers that wash the beet juice out using hot water. The juice is then used to pre-scald the cossettes so that the juice mixture can absorb more sugar.
Clarifying the Juice
Following the extraction, for both cane and beet juice, the juice must be clarified with milk of lime and carbon dioxide. In this process the juice is pushed through a decanter, heated, and mixed with lime before passing though carbon filters producing a mud-like substance. Referred to as carb juice, the resulting mud is pumped through a heater and then into a clarifying machine. Next, the cane or beet juice is separated from the waste mud by means of vacuum filtration, using liquid ring vacuum pumps like the Atlas Copco AWL series.
Evaporation and Concentrating
Once clarified, the remaining juice is pumped into an evaporator that boils out the water. What remains is a thick syrup like substance. The syrup, which is heavily concentrated, goes through several stages of vacuum boiling. Using vacuum pumps like the Atlas Copco LRP VSD+ liquid ring vacuum pump, the syrup under vacuum is able to be boiled at a much lower temperature, ensuring the concentrated syrup does not scorch or burn. While boiled the sugar begins to crystalize creating a substance called massecuite. The massecuite is poured into a centrifuge for further separation or the crystals from the syrup. Spun with significant force in the centrifuge, the crystals fall away from the syrup and the remaining product is – you guessed it – molasses.
Storage and Bottling
Following the separation, molasses is ready to be bottled. The final product is piped into large storage tanks where it is pumped into bottle machines. The bottles, being moved along a conveyor using air compressors like the Atlas Copco air-cooled, oil-free ZT160 VSD or water-cooled, oil-free ZR315 VSD, are then filled with pre-measured amounts of molasses and are ready to be capped, labeled, and shipped.
So, while waiting 8-10 minutes for those delicious gingerbread cookies to finish in the oven might feel like an eternity, keep in mind the long journey the main ingredient had to take before it made its way home with you. It’s well worth the wait, and we’re glad our compressed air and vacuum products play a part in such a classic Holiday tradition.