Sourdough bread is made by the fermentation of dough using naturally-occurring lactobacilli and yeast. Sourdough bread has a mildly sour taste not present in most breads made with baker's yeast and better inherent keeping qualities than other breads, due to the lactic acid produced by the lactobacilli.

Introduction

Sourdough is a dough containing a Lactobacillus culture in symbiotic combination with yeasts. It is one of the principal means of biological leavening in bread baking, the others using cultivated forms of yeast. It is important in baking rye-based breads, where yeast does not produce comparable results.

Preparation

Starter

The preparation of sourdough begins with a pre-ferment (the "starter" or "leaven", also known as the "chief", "chef", or "head"), made of flour and water, containing a colony of microorganisms including wild yeast and lactobacilli. The purpose of the starter is to produce a vigorous leaven and to develop the flavour of the bread. In practice there are several kinds of starters, as the ratio of water to flour in the starter (hydration) varies. A starter may be a liquid batter or a stiff dough.

Coordinates: 64°3′25″N 139°26′10″W / 64.05694°N 139.43611°W / 64.05694; -139.43611

The Klondike Gold Rush was a migration by an estimated 100,000 prospectors to the Klondike region of the Yukon in north-western Canada between 1896 and 1899. Gold was discovered there by local miners on August 16, 1896 and, when news reached Seattle and San Francisco the following year, it triggered a stampede of would-be prospectors. Some became wealthy, but the majority went in vain. The Klondike Gold Rush ended in 1899 after gold was discovered in Nome, Alaska prompting an exodus from the Klondike. It has been immortalized by photographs, books, films, and artifacts.

To reach the gold fields most took the route through the ports of Dyea and Skagway in Southeast Alaska. Here, the Klondikers could follow either the Chilkoot or the White Pass trails to the Yukon River and sail down to the Klondike. Each of them was required to bring a year's supply of food by the Canadian authorities in order to prevent starvation. In all, their equipment weighed close to a ton, which for most had to be carried in stages by themselves. Together with mountainous terrain and cold climate this meant that those who persisted did not arrive until summer 1898. Once there, they found few opportunities and many left disappointed.