Now, What About Molasses?

Molasses isn’t just caramelized sugar and browned proteins. “There are a lot of minerals, mostly calcium and iron,” says food scientist and author Harold McGee. “They don’t participate in any aromatic compounds themselves, but they influence the direction of reactions and give a distinctive spectrum of flavors. And besides sucrose, there are larger sugars, 3-and 4-unit sugars, which don’t have much sweetness but react with each other and the smaller sugars, giving flavorful compounds.”

Finally, there are amino acids from protein breakdown, which give molasses its sharpness.

Because of the acids, molasses or even brown sugar will make milk curdle if you boil it with either of them. For this reason, many recipes for butterscotch sauce, and particularly for butterscotch pudding, begin by cooking the brown sugar with butter before adding cream or milk--especially milk.

“This doesn’t actually prevent coagulation,” McGee says, “but it makes it less noticeable. The fat will disperse the coagulating milk proteins so they don’t link up to make larger clots.”

One absolute way to prevent curdling in a butterscotch pudding would be to use granulated sugar instead of brown sugar and then whisk in a little molasses--starting with a quarter of a teaspoon per cup of sugar and adding more to taste--at the very end, when it’s thickened. You can also use granulated sugar and a little molasses in place of brown sugar if you don’t have brown sugar on hand.