What is Molasses – History, Production and Manufacturing.

April 21, 2020


A bowl full of molasses with a spoon

What is Molasses?

Molasses, also known as black treacle, is a thick syrup which is a by-product of the sugar refining process. Its name originates from the Latin word ‘melaceres’ meaning ‘honey-like’ as it is extremely viscous. Molasses is the result of sugar crystallizing out of sugarcane or sugar beet juice during the clarification stage of sugar refining. It is extremely diverse and is used primarily for sweetening and flavouring food products, home baking, brewing ale, distilling rum, animal feed, flavouring tobacco products and as a defining component of commercial brown sugar. When asking the question ‘what is sugar’, molasses


The crystallization process required to produce molasses from sugarcane was first developed in India as early as 500 BC. However, it was not until much later that this process began to spread to the rest of the world. Arab invaders eventually brought the process from India to Spain in the Middle Ages, however the global diffusion of the process was really down to Christopher Columbus. After landing in the Canary Islands in 1493, he brought sugarcane to the West Indies where the production of molasses proved to be very lucrative.

Molasses grew to be extremely prominent during the late seventeenth century in the notoriously tragic slave trade triangles and was referred to as the ‘Colonial molasses trade’. African slave traders who brought their slaves to the West Indies often used to buy English rum and then take West Indian molasses to England. In the eighteenth century, sugar-refining produced a much higher molasses to sugar ratio than it does today, with an estimation of production being three parts molasses to four parts sugar. This molasses was primarily used for producing rum.

The trading of Molasses was unrestrained when it first began except for small local taxes. American colonies began to prefer French molasses over British because their policy provided much cheaper prices which Britain could not compete with. As a result, the Great British Parliament made the decision to impose high taxes on any molasses that was shipped from a foreign power to North American colonies. This ‘Molasses Act of 1733’ imposed a six pence fee per gallon on foreign molasses with the intention that the colonies would have to buy British molasses or stop producing rum. Instead however, the colonies ignored the new Molasses Act and thought it would be better to smuggle molasses from the West Indies rather than to comply with the prohibitive taxes. The illicit smuggling of molasses continued for many decades and had it not been for these illegal operations, the New England rum production would have undoubtedly been destroyed.

Production and Trading

Raw sugar

Brazil has been the largest producer of molasses over the last decade closely followed by India and Thailand. It is important, especially for countries with hot climates like Brazil, to uphold 3 key areas of focus when producing and trading molasseshttps://www.czarnikow.com/blog/the-sugar-series-the-top-10-sugar-producing-countries-in-the-world: temperature, TRS – Total Recoverable Sugar and Brix – sugar content. Temperature is extremely important to keep in mind when producing molasses. If the weather is too hot, for example above 45°C, or if the molasses is taken straight from production for delivery whilst it is still hot and without any conditioning, there is a high risk of the molasses foaming. If foaming occurs, the hot molasses can overflow from the delivery trucks and therefore product is lost on the journey between the mill and the final consumer plant. In order to control the risk of foaming, haulage companies now tend to use tanker trucks made of stainless steel and in this way, they can conserve the temperature of the molasses despite the temperature outside.

As mentioned previously, molasses has a diverse range of uses. For this reason, TRS is another essential component to consider when trading molasses; depending on the industry consuming the molasses, and indeed the final product that will be made, molasses with higher/lower TRS may be required. In the commercial production of yeast, molasses is used to provide the sugar source, and these yeast-producing industries require 63% TRS as their maximum. However, industries that produce valine (an important component in the animal feed market) require a minimum of 65% TRS. These are clear examples of why it is so necessary for molasses producers to think about the final desired use of their product when making molasses.

Finally, brix is the third crucial aspect to bear in mind when trading molasses. Brix is a metric value that verifies the sugar content inside the molasses. Usually the minimum brix required is 82% and this is something that final buyers are certain to take into account. If the mill delivers molasses with brix lower than 82% then the final buyer may have the right to ask for a discounted price as they have received a ‘lighter’ product therefore have less raw sugar material to be used for their final output.

Manufacturing Process

The primary ingredients for the sugar process of which molasses is a by-product are sugarcane and sugar beet. Other raw materials used in the process include limewater and carbon dioxide. Limewater, also known as ‘milk from lime’, is used in the sugar clarification process and is produced by heating limestone in a kiln. The limestone then gets mixed with sweet water from a previous clarification process to produce limewater. Carbon dioxide is released in this limewater process, it is purified in tanks and also used in the clarification of the sugar juice.

Regardless of whether the base is sugarcane or sugar beet, the sugar refining process of which molasses is a by-product is a cyclical process of washing and heating the cane or beets in hot water. The next step is the extraction of the sugar juice which for sugarcane can be accomplished in one of two ways: diffusion or milling. Using the diffusion method means that the cut stalks are dissolved in limewater whereas in the milling method, the stalks are passed under a series of heavy rollers in order to squeeze out the juice. For sugar beet, the sliced beet roots are loaded into cylinder diffusers which then wash out the juice with the help of hot water.

Clarifying the sugar juice is the next step in the process and it is at this stage in which molasses is produced. The juice, once clarified with limewater and carbon dioxide, is piped into a decanter, heated with lime and passed through carbon filters which results in a mud-like substance known as ‘carb juice’. The carb juice is then pumped through a heater to a clarifying machine which repeats the treating process with carbon dioxide. The carb juice is filtered out and leaves behind a pale-yellow liquid called thin juice, as mentioned previously in the sugar series. The juice is boiled to the point that only syrup remains, which is then concentrated through further vacuum boiling until sugar crystalizes out of the syrup creating a substance called ‘massecuite’. Massecuite is poured into a centrifuge which separates the sugar crystals from the syrup. Finally, this syrup left behind in the centrifuge is molasses!


As sugar is so often used in food and drink products which are generally deemed ‘unhealthy’, it may come as a surprise that commercial molasses in fact has multiple health benefits. Molasses is packed with nutrients such as iron, calcium, magnesium, selenium and vitamin B6. These nutrients mean that molasses has many beneficial properties. For example, molasses promotes good bone and tissue health because it’s rich in calcium and iron and research shows that it can even help with arthritis. Molasses is also a good antioxidant therefore can increase red blood cell formation and maintain haemoglobin levels – it is often used in the preparation of anti-inflammatory medication. The antioxidants found in molasses can even help your hair as an anti-ageing conditioner.

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Author: Betty Rook

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