Changes

A dextrinous wort consisting of a high concentration of maltooligosaccharides may be produced by different mashing procedures. The most traditional method of achieving this is through a [[Turbid Mash|turbid mash]]. With this mashing technique, unconverted [[File:Homebrew Turbid Mash Pull.jpeg|200px|thumb|right|First pull of turbid runnings in a homebrew turbid mash]] starchy wort (which is 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 <ref name="Burgundian Babble Belt discussion">[http://www.babblebelt.com/newboard/thread.html?tid=1108752780&th=1243453104 Burgundian Babble Belt discussion]</ref> passing hot mash runnings through flaked grains <ref name="Flat Tail on the Brewing Network">[http://thebrewingnetwork.com/shows/1027/ Flat Tail on the Brewing Network, ~1:04 in]</ref>, or pulling mash runnings before full conversion without the prolonged processing of a turbid mash <ref name="Flat Tail on the Brewing Network" />. Whichever technique is employed, the goals are the same - to provide starches which ''Saccharomyces cerevisiae'' and ''Saccharomyces pastorianus'' cannot ferment and which can feed the diverse combination of other yeasts and bacteria present.

Although creating a dextrinous wort is traditional for spontaneous fermentation, it is not necessarily a microbiological requirement. Traditional [[Lambic]] must use a turbid mashing process for the sake of tradition, but non-lambic spontaneous fermentations can also be successful using simpler methods such as single infusion mashes. Not having the dextrins available for the microbes during long-term aging might change the fermentation profile and produce a different type of product (for example, with fewer dextrins there might be less acidity produced from the slow acting ''Pediococcus'', but ''Brettanomyces'' does not rely solely on dextrins to produce its flavor contributions and fewer dextrins will accomplish a faster stable final gravity). Many brewers outside of Belgium have experimented with doing spontaneous fermentation with wort that was not produced from a turbid mash (references needed). Additionally, the maltooligosaccharides produced by turbid mashing can be broken down earlier in the fermentation process by other species such as ''Saccharomyces kudriavzevii'' and acetic acid bacteria <ref name="Bongaerts_2021">[https://pubmed.ncbi.nlm.nih.gov/34232060/ Bongaerts D, De Roos J, De Vuyst L. Technological and Environmental Features Determine the Uniqueness of the Lambic Beer Microbiota and Production Process. Appl Environ Microbiol. 2021 Aug 26;87(18):e0061221. doi: 10.1128/AEM.00612-21. Epub 2021 Aug 26. PMID: 34232060; PMCID: PMC8388830.]</ref>.