What Is Molasses? Sources, Types, and Surprising Uses

Molasses does not come from a tree. It's a thick syrup by-product of refining sugarcane or sugar beet into sugar. The word traces to Portuguese melaço, from Greek mellas (honey).

Cane Molasses

• Sulphured: Made from green (unripe) cane, treated with sulfur fumes.
• First molasses: From the first boiling—highest sugar content.
• Second molasses: From a second boiling—slightly bitter.
• Blackstrap: Third boiling—most sucrose removed, but rich in calcium, magnesium, iron (1 tbsp ≈ 20% DV each). Sold as a health supplement and used in cattle feed.

Sugar Beet Molasses

Only the final crystallization syrup is called molasses; intermediate syrups are recycled. It's ~50% sugar (sucrose, glucose, fructose) but high in salts (calcium, potassium, oxalate, chloride), making it unpalatable—mainly used for animal feed or fermentation feedstock. Desugarization via chromatography can recover extra sugar in protected markets (US, EU).

Trivia & Uses

• Chelating agent: 1:9 molasses:water removes rust in two weeks.
• Boston Molasses Disaster (1919): Tank burst killed 21, injured 150.
• Treacle tart uses golden syrup, not molasses.
• Rum fermentation base.
• Bioremediation: Carbon source for chlorinated hydrocarbon cleanup.
• ANFO explosive fuel (largely discontinued).
• Radiohead has a B-side titled "Molasses."