Sourdough - includes related articles on making sourdough - recipes

Sunset, May, 1988

Sourdough

Since gold mining days, sourdough has been a Western staple, delighting generations with its tangy flavor in breads, pancakes, and other baked foods.

Sourdough has been a standby at Sunset, too, from the first recipes published in 1933 to a longer discussion in 1961. A breakthrough story in 1973 gave directions for creating a dependable starter-- the mixture of flour, liquid, and beneficial bacteria that put the tang in sourdough baking; ours was based on yogurt.

Two years ago, we asked you to write us about your sourdough experiences, especially with the yogurt-based starter. We received hundreds of responses--as well as many questions. To answer these and our own questions, we embarked on sourdough experiments. (Some most-asked questions are discussed on page 140.) In brief, we found that starters are much more forgiving of neglect and variations in feeding than we had thought. You can change your technique to encourage more or less sour flavor, and you can use the starter in quick or more involved ways.

Readers also sent many recipes; favorites are pictured at left and on page 141.

Yeasts and beasts--how a starter works

No sourdough starter is exactly like another: each is a living organism with a different bacteria and yeast make-up. All starters ferment flour and liquid (usually milk or water): bacteria break down sugars in the flour and milk and produce acids, primarily lactic acid and some acetic acid (vinegar); these give sourdough its tang. Fermentation also produces some carbon dioxide bubbles.

Our 1973 recipe relies on bacteria in the yogurt to culture the starter. These bacteria may be different from ones in commercial starters, or in homemade ones that capture bacteria more haphazardly.

While bacteria create sourness, yeasts break down sugars in flour to form more carbon dioxide, which leavens the bread.

Yogurt-based starters typically don't have any yeast, although you may have the good fortune to capture some from flour (yeasts are not airborne, as lore suggests).

Because starters vary so much in their leavening ability, our recipes contain another leavener as well. We don't think commercial yeast detracts from the sourdough taste; it just adds another flavor. And bread made with yeast rises faster than with starter alone--about 1 1/2 hours versus 6 to 8 hours.

Care and feeding of your pet starter

To keep bacteria and yeasts healthy, a starter must be fed flour and liquid occasionally, then stand. (Chill between uses.) For food choices, see box on page 140.

Environment. When creating a starter, incubate it between 80| and 90|: higher, and bacteria may die; lower, the starter may develop mold. Place stop your water heater--or in an oven with the light on or warmed with pans of boiling water.

An established starter is stronger; after feeding, it can stand at room temperature if a warm spot isn't handy. If you feed the starter milk, as we suggest, you'll know it's ready to use or chill when a clear liquid forms on top. This shows that the acid level has risen and is starting to break down milk protein. High acid means sour flavor.

Bacteria in starters grow best without oxygen, so store your starter in a tightly closed container. Air fosters mold, too.

Neglect or care? In our 1973 story, we suggested feeding the starter every two weeks. Some readers who ignored this wrote with revival tales worthy of Southern evangelists: after starters had nearly died from international travel, natural disasters, and lack of food for up to two years, they revived. (Other readers guilty of such cavalier tactics lost their starters.)

For more on ignoring starters, see the question box on page 140.

A happy medium between neglect and slavish attention is to feed the starter at least once a month. If it has sat in the refrigerator longer, try reviving it.

Resuscitate or give up the ghost?

An "old" smell, no bubbles at room temperature, a top layer of dark brown liquid, and slight mold growth indicate your starter isn't feeling its best. First spoon off and discard any mold, then stir the starter. Feed it 1 cup each of flour and milk and let stand as directed in the recipe. After 24 hours, discard half the starter and repeat feeding and standing. Repeat a third time, if needed, until starter bubbles, has a "fresh" sour smell.

You can't bring a starter back from the dead. If, after repeated feedings, your starter still smells "off" and won't bubble, discard it. Also, if mold growth is heavy, begin a new starter.

Getting the most flavor, best texture

Increasing the tang in your sourdough baked foods and getting chewy, light texture require surprisingly few acrobatics.

Sourness. The greatest trick for more sour flavor is patience: the longer dough stands in the "sponge" stage, the more sourness you'll get--up to a point. A sponge is a mixture of starter and part of the liquid and flour called for in a recipe. You let it stand 12 to 24 hours before adding other ingredients; as it stands, bacteria multiply and produce acidity, or sourness. After about 24 hours, the sponge won't get much more sour. Our recipes give you the option of a long sponge stage for flavor or a short one for speed.