Hop Yeast
Place a handful of hops in two quarts of cold water, boil slowly for a half hour, strain boiling hot on one pint flour and one table spoon salt (gradually at first in order to mix smoothly); when lukewarm add a half pint of yeast, and set in a warm place to rise. When light, cover and keep in a cool place. -Mrs. M. J. Woods.
A liquid bread starter of the sort a nineteenth-century household kept going from week to week. It is not a from-scratch culture: it needs a half pint of live yeast to begin, so you must either have an active starter already or substitute.
- The seed yeast is the hingeThe half pint of yeast added at lukewarm is the whole ferment; the hops and flour only feed and preserve it. Without an active liquid starter to hand, dissolve a teaspoon of commercial dry yeast in a little warm water and use that, then treat the result as a maintained starter.
- Temperature matters more than time"When lukewarm" means blood-warm, roughly 95-105F. Do not add the seed yeast while the hop-and-flour scald is still hot: too much heat will kill it and the batch simply will not rise.
- A handful of hopsRoughly half an ounce to an ounce of dried whole hops, which is a bulky handful of cones. Any bittering variety from a brewing supplier works. The bitterness acts as a preservative, discouraging spoilage bacteria while the yeast establishes itself.
- Strain boiling hot, and pour slowlyThe hot hop tea cooks the flour into a thin paste. Add the first cup or two in a trickle while whisking or you will get lumps that never disperse.
- What "light" looks likeTypically several hours in a warm room, depending on the vigor of the seed. The surface will be foaming and domed, with a yeasty, faintly beery smell. The recipe covers and chills it at this point.
- Keeping it"A cool place" meant a cellar or springhouse, about 50F. In a covered jar in the refrigerator it holds a week or two; stir before using, as the flour settles hard. Discard if it smells of acetone, cheese, or vinegar, or shows any colored mold.
- Yield and useAbout two quarts, enough to raise several batches of bread. Older bread recipes calling for "one cup yeast" or "a teacup of yeast" mean this kind of liquid ferment, not modern dry yeast, and cannot be substituted measure for measure.
Before packaged yeast, households kept a wet ferment alive on the kitchen shelf, and hop yeast was one of the types found in nineteenth-century cookbooks. Hops came into the recipe from brewing, where their antibacterial resins had long been valued for keeping beer sound; in a flour-and-water starter they served the same purpose, slowing the souring organisms that would otherwise overtake the yeast in a warm kitchen. Books of this period usually give several yeast recipes side by side \, pot, salt-rising, milk \, because a cook who lost her starter had to borrow or begin again, and the section functioned as insurance. Compressed cake yeast reached American grocers in quantity in the last decades of the century, though home-made hop and potato yeasts went on appearing in printed cookbooks well into the twentieth century \, which is roughly why such books devote space to something no modern cookbook bothers to explain.