Spontaneous Fermentation

Spontaneous Fermentation, for the purposes of this article, refers to the fermentation of wort by inoculating it in a coolship where the wort is left exposed to the air and allowed to cool naturally over night. Wild yeast and bacteria are introduced into the wort as it cools. It is the traditional method of brewing Lambic .

Defining Spontaneous Fermentation

(To do)

Spontaneous Fermentation versus Mixed Fermentation

(To do) - talk about the differences between spontaneous fermentation and Mixed Fermentation, and the arguments for using different methods.

Brewing Methods

The traditional production of spontaneously fermented beer employs three main ---points---: the production of a dextrinous wort, high hopping rates with aged hops, and inoculation of the wort with a coolship. Not all breweries producing spontaneously fermented beer employ these three techniques, but they are generally common among producers.

A dextrinous wort may be produced by different mashing procedures. The most traditional method of achieving this is through a turbid mash. With this mashing technique, unconverted starchy wort (which turbid in appearance)is pulled from the mash and heated to denature enzymes. These pulled runnings are then replaced by infusions of hot water as the mash is carried through a series of steps for conversion of the remaining grains. The starchy wort from the early 'turbid' pulls is carried to the boil with incomplete conversion, providing dextrins to sustain brettanomyces and lactic acid bacteria in a prolonged mixed fermentation. Other methods to carry unconverted dextrins into the boil may be employed such as the addition of flour (----add source----), passing mash runnings through flaked grains (---flat tail on the brewing network---), or pulling mash runnings before full conversion without the prolonged processing of a turbid mash. Whichever technique is employed, the goals are the same - to provide starches which Saccharomyces cerevisiae and Saccharomyces pastorianus can not ferment and which can feed the diverse combination of other yeasts and bacteria present.

High hopping and aged hops

Coolship (Anglicized version of the Dutch/Flemish koelschip) is a type of fermentation vessel used in the production of beer. Traditionally, a coolship is a broad, open-top, flat vessel in which wort cools. The high surface to mass ratio allows for more efficient cooling. Contemporary usage includes any open fermentor used in the production of beer, even when using modern mechanical cooling techniques. Traditionally, coolships were constructed of wood, but later were lined with iron or copper for better thermal conductivity.

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  Homebrew 15 Gallon Coolship

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  Homebrew 15 Gallon Coolship

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  30 Barrel Coolship from Funk Factory

External Resources

A list of external internet resources and articles for spontaneous fermentation.

• Link 1
• Link 2
• Link 3

See Also

• Scientific publications
• Lambic
• Gueuze
• Fruit Lambic
• Brettanomyces
• Pediococcus
• Lactobacillus
• Flanders Red Ale
• Oud Bruin
• Mixed Fermentation