Karo Candy
1/2 cup cream 1 cup Karo syrup 1½ cups brown sugar 1/2 tablespoon butter 1/2 cup chopped walnuts Boil together the cream, syrup and sugar. Test by dropping a little in cold water, and when almost done add the butter and walnuts. Remove from fire; beat until creamy; empty into a buttered pan; mark off in squares and set aside to cool.
A plain penuche-style fudge built on corn syrup, which keeps the crystals fine. The whole recipe turns on how far you cook the syrup, and the original leaves that to the cold-water test.
- The hinge: cook to a firm ballThe hinge: cook to a soft ball -- "Almost done" in the cold-water test for a beaten candy of this type means a soft ball — a blob that flattens between the fingers when lifted from the water, roughly 234-240F on a candy thermometer, though the original gives no reading. Under-cooked it will never set past a sauce; over-cooked it turns hard and dry.
- KaroKaro is a corn syrup brand, still sold under that name, in light and dark versions; light is what suits this recipe. Any light corn syrup works; golden syrup is darker and more acidic and will change the flavor. Do not substitute high-fructose syrup or maple syrup.
- Cream"Cream" in this period was not a standardised product and was often thinner than modern heavy cream, plausibly in the range of a modern light cream. Modern heavy cream (36 percent) is richer than likely intended; light cream or half-and-half is closer, and either will scorch if the heat is high, so stir until the sugar dissolves and keep the boil moderate.
- Half a tablespoon of butterThat is 1 1/2 teaspoons, about 7 g. The recipe adds it near the end of the boil, with the nuts, just before the pan comes off the fire; it softens the grain rather than enriching the candy.
- BeatingThe original beats straight off the fire. Modern practice is to let the syrup cool undisturbed to about 110F first, then beat until it loses its gloss and thickens; beating while it is still hot tends to give a coarse, grainy candy. Pour the moment it stiffens or it will set in the pot.
- Pan and yieldThe batch runs to something over a pound, which will give a thin layer in an 8-inch square pan; a smaller pan gives a better depth.
- Marking offScore the squares while the candy is warm and still yielding. Once cold it fractures rather than cuts.
Karo syrup was introduced by the Corn Products Refining Company in the early 1900s, and its marketing leaned hard on home candy-making: corn syrup interferes with sucrose crystallization, so a cook could produce smooth fudge and caramels without the finesse that all-sugar candy demanded. Branded recipes like this one circulated through company pamphlets and were copied into community and loose-leaf cookbooks, which is how a trade name ends up as the title of a dish. The candy itself is essentially penuche — brown-sugar fudge, generally traced to New England, where the name is usually explained as a borrowing of the Mexican Spanish panocha for raw or coarse sugar.