When Alaskan gold seekers put away their gold pans at the end of the day, they picked up their baking pans and a scoop of sourdough. Although the nickname "Sourdoughs" will forever belong to Alaska's gold rush era, the skills of sourdough baking go back centuries. We don't know who first cloned the luscious tang of dough-gone-sour, but the Marquis de Rochambeau of France is credited with bringing the first sourdough starter to the Americas with Lafayette's army during the American Revolution.

How did sourdough evolve from a mere baking convenience into a legend, a taste sensation found on the tables of almost every cruise line, and a passion for millions of cooks?

Leavened bread has been known to humankind for thousands of years. People of the Swiss Lake cultures were accomplished bakers 10,000 years ago. Perfectly-formed loaves were found in Egyptian tombs. By the year 100 B.C., Rome had more than 250 bakeries.

Not just wheat but many grains and other flours, such as acorn and bean, have served as a staff of life for many cultures. It didn't take people long to discover that (1) baked goods are much lighter and tastier when bubbles are baked into the dough and (2) the air is filled with wild yeast spores that can be captured and cultivated to create those bubbles.

Therein lies the magic of sourdough. The familiar yeast sold in the supermarket is just one of many yeasts. It's a known quantity, one that produces the same result with every loaf, kolache, kuchen and kaiser roll. Sourdough, by contrast, is a living culture that is unique to its beginnings. Best of all, it evolves constantly to remain forever unique depending on the home it lives in and the householder who handles it. It can be started with commercial yeast, but it can also be started just by setting out a bowl of warm potato water and flour that picks up whatever spores are floating around the kitchen at the time. Each time it returns to the kitchen counter, it can collect new flora.

Sourdough is a living thing, to be sheltered and propagated much as one takes care of a beloved plant. The easy way to become a sourdough baker is to purchase starter or get some from a friend. In fact, in some circles sourdough sharing is a rite of friendship much like passing along a slip of a plant or a packet of seeds. With as little as a walnut-size chunk, you can inoculate a bowlful of flour and water with yeasty goodness that grows to full potency in 24 to 48 hours.

Entire books are published on the how and why of sourdough. It's used in hundreds of recipes from bread and rolls to biscuits, cookies, croissants, waffles, muffins, pizza and even chocolate cake. Gold Nugget Morrison was known for the Sourdough Applesauce Cake she served at her sporting house in Anchorage. Russians in Sitka ate Sourdough Donuts and Sourdough Fruitcake Baranov. Jake O'Shaughessey's saloon opened in Seattle in 1897 serving food, drinks, and his famous sourdough bread.

In addition to its taste benefits, sourdough is a lot cheaper than buying baker's yeast. It's also easier to keep on hand in the wilderness than baking powder, which is perishable. Pioneers used it for leavening, for glue, and as a polish for brass and copper. They made merry by drinking the alcohol, called hooch, that rose to the top of the crock. Those who had time and inclination even distilled the hooch into potent "white mule."

What's not to love about a living thing that is as helpless as a baby? It must be fed, burped, and kept at just the right temperature. Owners become downright parental over their sourdough starters. Pioneers often worked sourdough into flour, creating dry doughballs that could be carried for weeks without refrigeration. They stayed dormant until they were once again provided the moist, warm environment required to get them swelling and growing again. Starter can also be frozen and thawed but, to be on the safe side, early Alaskans sometimes slept with their starters to keep them warm. To lose one's starter in the dead of winter was a catastrophe.