Sourdough bread is traditional bread using the same recipes and techniques used by bakers before the 1900's. An artisanal product, it dates back to 10,000 BC in Egypt and is the original method of bread making. William & David Arnott made sourdough bread when they arrived in Morpeth in 1847. See left David Arnott's advert in 1891 for the "patent yeast recipe" to avoid making sourdough bread.
It wasn't until the 1880's that Saccharomyces cerevisiae (aka baker's yeast) was cultivated for commercial use and revolutionised the bread industry. In Australia, some 100 years later, sourdough bread has made a come back as the nutritional qualities and health properties far outweigh commercially produced yeasted bread.
Technically, sourdough bread is made using only high quality flour, purified water and sea salt and every loaf is hand-shaped. There is no additives used, that is, no baker's yeast, preservatives, raising agents, emulsifiers, stabilisers, extenders or bulking agents in any sourdough products.
The texture and taste of sourdough are purely the result of the extended dough fermentation by the naturally occurring microorganisms, such as wild yeast and lactobacilli. The long fermentation (proving), enables the flavour compounds in flour to develop and the gluten to convert fully. The result is a pronounced earthy flavour and dense texture that is more easily digested than yeasted bread.
During fermentation, wild yeasts produce carbon dioxide, making dough rise and lactobacilli produce organic acids, giving the bread its unique and distinct flavour. Lactobacilli also produce compounds which stimulate the immune system, as well as anti-fungal compounds, which inhibit some of the major mould species that spoil bread. As a result, authentic sourdough bread does not stale as quickly as yeasted bread.
Like fine wine and cheese, complex flavours result from natural fermentations. Other fermented foods are salamis etc, tofu (fermented soybean), soy sauce, miso, balsamic vinegar, European dairy products such as buttermilk, cultured butter, cheese, naturally brewed beer, sauerkraut, fermented fish, vegetables etc.
