Online dating for science geeks Horny teens chat room
Bread made from 100% rye flour, popular in the northern half of Europe, is usually leavened with sourdough.
Baker's yeast is not useful as a leavening agent for rye bread, as rye does not contain enough gluten.
Bran-containing (wholemeal) flour provides the greatest variety of organisms and additional minerals, though some cultures use an initial mixture of white flour and rye or whole wheat flour or "seed" the culture using unwashed organic grapes (for the wild yeasts on their skins).
Grapes and grape must are also sources of lactic acid bacteria, Using water from boiled potatoes is said to increase the activity of the bacteria by providing additional starch.
Firm starters (such as the Flemish Desem starter, which may be buried in a large container of flour to prevent drying out) tend to be more resource-intensive than wet ones. sanfranciscensis is the dominant bacterium requires a temperature between 25–30 °C (77–86 °F) and refreshments every 24 hours for about two weeks.
Refreshment intervals of longer than three days acidify the dough and may change the microbial ecosystem.
A drier and cooler starter has less bacterial activity and more yeast growth, which results in the bacterial production of more acetic acid relative to lactic acid.
Bread production relied on the use of sourdough as a leavening agent for most of human history; the use of baker's yeast as a leavening agent dates back less than 150 years." until being replaced by barm from the beer brewing process, and then later purpose-cultured yeast.
Acidity levels of below p H 4.0 inhibit lactobacilli and favour acid-tolerant yeasts.
A starter prepared from scratch with a salted wheat-rye dough takes about 54 hours at 27 °C (81 °F) to stabilise at a p H between 4.4 and 4.6.
San Francisco sourdough is a white bread characterized by a pronounced sourness, and indeed the strain of Lactobacillus in sourdough starters is named Lactobacillus sanfranciscensis, alongside the sourdough yeast Candida milleri found in the same cultures.
The sourdough tradition was carried into Alaska and the western Canadian territories during the Klondike Gold Rush of 1898.