Treacle vs. Molasses: 4 Key Differences Between the Syrups

Treacle is an uncrystallized syrup that forms during the sugar-making process. Commonly known as the British version of molasses, treacle is thick and dark, with a sweet, mild bitterness. The syrup is a common ingredient in sweet recipes and baked goods, including ginger cakes, fruit cakes, sticky toffee pudding, and treacle tarts.

There are several grades of treacle available in most grocery stores, ranging from light treacle (or golden syrup), which is the lightest and sweetest, and dark treacle or black treacle, which is darker and more bitter.

Molasses is a thick, dark syrup that forms during the sugar-making process. The syrup is thicker and darker than treacle, its British counterpart, with a sweeter, more intense flavor. Molasses is a common ingredient in sweet and savory recipes, including gingerbread cookies, molasses bread, barbecue sauce, beers, baked beans, and chilis. Manufacturers also add it to white cane sugar to produce brown sugar.

You can typically find three different types of molasses in grocery stores: light, dark, and bootstrap. Light molasses is light and sweet, while dark molasses is a darker, more bitter variety. Blackstrap molasses is the darkest and most bitter of the three. In addition, molasses can come sulfured or unsulfured (referring to the addition of sulfur dioxide as a preservative).

In general, the flavor profiles and textures are similar enough that you can substitute treacle and molasses for one another in most recipes without issue.

Other substitutes include maple syrup, dark corn syrup, light corn syrup, agave, sorghum (sometimes called “sorghum molasses”), or honey, though these options will dramatically alter the dish’s taste.

Treacle and molasses are two very similar byproducts of sugar-making with slightly different uses in the kitchen:

1. 1. Production: Treacle and molasses are types of sweet syrup that form during the sugar-refining process. To make the syrups, manufacturers extract juice from sugar cane and sugar beets, boil it to produce sugar crystals, and remove the sucrose crystals to preserve the remaining liquid (molasses or treacle). The major difference between molasses and treacle (and their various grades) comes from the length of time that manufacturers boil the sugar syrup mixture. Typically, molasses boils for far longer, resulting in a darker, thicker liquid with less sugar; with a shorter boiling time, treacle is often lighter and thinner with more sugar.
2. 2. Flavor: While treacle and molasses both have a wide range of flavors depending on the grade, treacle tends to trend sweeter and less bitter, while molasses tends to be less sweet with a more bitter taste.
3. 3. Consistency: Since treacle undergoes a shorter boiling time, it retains more of its liquid properties and stays thinner. On the other hand, molasses undergoes a longer boiling time, releasing most of its liquid until it becomes thick and slow—it’s a popular American expression to say something is “as slow as molasses.”
4. 4. Uses: Due to its consistency and sugar content, treacle is a popular sweetening agent in sweet recipes, desserts, and baked goods, where it can offer additional moisture to the dry ingredients. On the other hand, molasses is thicker and more bitter, so while it’s a sweetener in many sweet treats, it’s also popular in savory recipes like sauces, glazes, marinades, and stews.

Become a better chef with the MasterClass Annual Membership. Gain access to exclusive video lessons taught by the world’s best, including Alice Waters, Gabriela Cámara, Niki Nakayama, Chef Thomas Keller, Gordon Ramsay, Yotam Ottolenghi, Dominique Ansel, and more.