Brewing Lambic: Difference between revisions
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The hot side of traditional lambic production involves a time and labor-intensive mashing process known as turbid mashing, where cloudy or turbid wort is removed from the mash before it is allowed to completely convert. This turbid wort contributes complex carbohydrates and proteins to lambic wort which can feed a diverse community of yeast and bacteria during the long lambic fermentation process. Lambic then undergoes a long boil where hops which typically have been aged at least a couple of years are added. Finally the wort is transferred to the coolship for overnight cooling. | The hot side of traditional lambic production involves a time and labor-intensive mashing process known as turbid mashing, where cloudy or turbid wort is removed from the mash before it is allowed to completely convert. This turbid wort contributes complex carbohydrates and proteins to lambic wort which can feed a diverse community of yeast and bacteria during the long lambic fermentation process. Lambic then undergoes a long boil where hops which typically have been aged at least a couple of years are added. Finally the wort is transferred to the coolship for overnight cooling. | ||
[[File:Cantillon_hops_aging.jpg|300px|thumb|right|2014 Perle hops aging at Cantillon, May 2016.]] | |||
==Raw Ingredients== | ==Raw Ingredients== | ||
The Royal Decrees of May 20, 1965 and March 31, 1993 required that lambic brewers use at least 30% wheat.<ref name=“GeuzeKriek”>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref> Today's modern lambic is brewed using a grain bill of roughly 30-40% raw (ungerminated) wheat and 60-70% malted barley (2-row or a combination of 2-row and 6-row). Recipes from the 1800s actually called for even more unmalted wheat.<ref name=Lacambre> G. Lacambre, Traité complet de la fabrication des bières et de la distillation, 1851.</ref> In most cases, both the wheat and the barley are coming from Belgian or German farms | The Royal Decrees of May 20, 1965 and March 31, 1993 required that lambic brewers use at least 30% wheat.<ref name=“GeuzeKriek”>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of Lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref> Today's modern lambic is brewed using a grain bill of roughly 30-40% raw (ungerminated) wheat and 60-70% malted barley (2-row or a combination of 2-row and 6-row). Recipes from the 1800s actually called for even more unmalted wheat.<ref name=Lacambre> G. Lacambre, Traité complet de la fabrication des bières et de la distillation, 1851.</ref> In most cases, both the wheat and the barley are coming from Belgian or German farms. | ||
Aged hops also play an important role in lambic. Hops are necessary | Aged hops also play an important role in lambic. Hops are necessary to regulate the growth of bacteria; however higher doses of fresh hops could add an unwanted level of bitterness. This is why hops over a year old are used; they have lost the majority of their bittering properties but not their bacteriostatic properties.<ref name=PalmBoon>Boon Brewery, Brewing Process http://palmbreweries.com/en/boon</ref> Traditionally, hops containing low amounts of alpha acids are aged for anywhere between a year and three years; although some bales of hops wind up aging much longer. The hops are typically stored in an environment where they are susceptible to oxygen and drastic temperature changes, such as in sacks in an attic, rather than the vacuum sealed and cold storage common for beers using un-aged hops. | ||
==Equipment== | ==Equipment== | ||
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===Hot side equipment=== | ===Hot side equipment=== | ||
[[File:Cantillon-Brewing-2.jpg|300px|thumb|right|Cantillon's mash tun]] | [[File:Cantillon-Brewing-2.jpg|300px|thumb|right|Cantillon's mash tun]] | ||
While some specialized equipment is used in the ‘hot side’ of lambic production, much of the equipment used in modern lambic breweries resembles the sort of equipment you would see in contemporaneous Belgian non-lambic breweries. The typical hot side equipment found in lambic breweries includes a mash tun with internal rakes, one or two boiling kettles, and a coolship. Additional necessary brewing equipment which may be more or less visible, depending on the brewery, includes a grain mill, access to hot water through either a dedicated vessel (termed a hot liquor tank) or through on-demand hot water, and pump(s) which are either belt-driven (e.g. [[Cantillon]]) or electrically powered (e.g. [[3 Fonteinen]]). Significant variability exists between different producers in the specifics of this equipment based on size and when the brewery was built, but their function and general characteristics are basically the same. | While some specialized equipment is used in the ‘hot side’ of lambic production, much of the equipment used in modern lambic breweries resembles the sort of equipment you would see in contemporaneous Belgian non-lambic breweries. The typical hot side equipment found in lambic breweries includes a mash tun with internal rakes, one or two boiling kettles, and a coolship. Additional necessary brewing equipment which may be more or less visible, depending on the brewery, includes a grain mill, access to hot water through either a dedicated vessel (termed a hot liquor tank) or through on-demand hot water, and pump(s) which are either belt-driven (e.g. [[Cantillon]]) or directly electrically powered (e.g. [[3 Fonteinen]]). Significant variability exists between different producers in the specifics of this equipment based on size and when the brewery was built, but their function and general characteristics are basically the same. | ||
The mash tuns used in lambic production deserve specific discussion before dealing with brewing process. A mash tun is the vessel that holds the mixture of grain and water (the mash) as enzymes in the grain are active to convert components of the grain into fermentable sugars and accessible nutrients for yeast and bacteria. Mash tuns have a false bottom made of a perforated or slotted screen which allows liquid to pass below while retaining the grain. Historically wooden baskets (called stuykmanden in Flemish) were also used to extract liquid from the mash. These baskets were pressed into the mash and turbid wort was withdrawn and transfered to a boil kettle<ref name=Lacambre/><ref name='Johnson 1918'>G.M. Johnson, 1918. A Belgian mashing system suitable for light beers. Journal of the Institute of Brewing. 24(6) 237-251.</ref>. Mash tuns have internal rakes which aid in mixing the mash as well as draining the sweet wort after the mash is complete. Along with the rakes, some lambic breweries (e.g. [[Timmermans]]) have perforated copper disks called extractors inside the tun which were used to help withdraw liquid from the mash.<ref name=Lacambre/><ref name='Johnson 1895'>G.M. Johnson, 1895. Brewing in Belgium and Belgian Beers. Journal of the Federated Institutes of Brewing. 1(5) 450-470.</ref>. | The mash tuns used in lambic production deserve specific discussion before dealing with brewing process. A mash tun is the vessel that holds the mixture of grain and water (the mash) as enzymes in the grain are active to convert components of the grain into fermentable sugars and accessible nutrients for yeast and bacteria. Mash tuns have a false bottom made of a perforated or slotted screen which allows liquid to pass below while retaining the grain. Historically wooden baskets (called stuykmanden in Flemish) were also used to extract liquid from the mash. These baskets were pressed into the mash and turbid wort was withdrawn and transfered to a boil kettle<ref name=Lacambre/><ref name='Johnson 1918'>G.M. Johnson, 1918. A Belgian mashing system suitable for light beers. Journal of the Institute of Brewing. 24(6) 237-251.</ref>. Mash tuns have internal rakes which aid in mixing the mash as well as draining the sweet wort after the mash is complete. Along with the rakes, some lambic breweries (e.g. [[Timmermans]]) have perforated copper disks called extractors inside the tun which were used to help withdraw liquid from the mash.<ref name=Lacambre/><ref name='Johnson 1895'>G.M. Johnson, 1895. Brewing in Belgium and Belgian Beers. Journal of the Federated Institutes of Brewing. 1(5) 450-470.</ref>. | ||
===Barrels=== | ===Barrels=== | ||
[[File:De_Troch_barrel_cleaning.jpg|230px|thumb|right|Barrel cleaning at De Troch]] | |||
While some larger producers are using stainless steel tanks, lambic is traditionally fermented and aged in wooden barrels and foeders. Lambic brewers and blenders prefer used barrels, which are often coming from red wine production, for fermenting and aging lambic. These barrels are preferred because most of the oak character has already been extracted from the barrel, and less character from the wood will come through in the final lambic. Barrels vary widely in size, including sizes such as 267 liter Tonnes, 550-650 liter Pipes, and 3,000 to 120,000+ liter Foedres. Each brewer has their preference for their ideal barrel size. These barrels are typically made from oak or chestnut. | |||
Each individual barrel can have its own progression, even among well used barrels and different barrels from the brewing day, and some lambic brewers and blenders are experimenting with more distinctive barrels where the influence of the previous contents of the barrel are desired. Increasingly, lambic producers are releasing beers highlighting the unique role that different barrels or foeders can have. This includes sourcing specific barrels or foeders for their characteristics as noted above, as well as bottling the first lambics from recently-received used barrels as separate releases, and releases highlighting a single foeder or selection of older barrels. Some examples of this are: | |||
Barrels used for spirits | |||
*[[Vat_110_Monoblend|Boon Vat 110 Monoblend]] (Cognac) | |||
*[[Boon/Mikkeller_Oude_Geuze_(Calvados_Aged)|Boon/Mikkeler Oude Geuze (Calvados Aged)]] (Calvados) | |||
*[[Cantillon_50_Degrees_North_-_4_Degrees_East|Cantillon 50N 4E]] (Cognac, Armagnac) | |||
*[[Cantillon_Chouke|Cantillon Chouke]] (Armagnac) | |||
Barrels used for oxidative wines | |||
*[[3_Fonteinen_Zenne_y_Frontera|3 Fonteinen Zenne Y Frontera]] (Sherry) | |||
*[[Cantillon_Lambic_Vin_Jaune| Cantillon La Vie est Belge]] (Vin Jaune) | |||
*[[Cantillon_Brabantiae|Cantillon Brabantiae]] (Port) | |||
First use(s) of wine barrels | |||
*[[Cantillon_Zwanze_2018|Cantillon Zwanze 2018]] (Amarone, Chianti, Sangiovese) | |||
*[[Oud Beersel Oude Geuze Vieille - Vandervelden 135|Oud Beersel Vandervelden 135]] (Brunello di Montalcino) | |||
*[[Oud_Beersel_Oude_Geuze_Vieille_-_Vandervelden_137|Oud Beersel Vandervelden 137]] (Brunello di Montalcino) | |||
Old barrels | |||
*[[Vat_79_Monoblend|Boon Vat 79 Monoblend]] (from a foeder built in 1883), along with many of the other monoblend series | |||
*[[Oud_Beersel_Oude_Geuze_Vieille_Barrel_Selection_Oude_Pijpen|Oud Beersel Oude Geuze Barrel Selection Oude Pijpen]] | |||
Barrel cleaning is important for lambic production; however, the exact methods used vary among individual brewers and blenders. Some basic steps are fairly universal. First, any sediment is removed from the barrels by spraying with hot water and, in some cases, scrubbing. Some brewers (such as Cantillon) scrape barrels clean by putting sharpened chains in the barrels and spinning them. The barrels are then washed extensively with with very hot water and/or steamed to sanitize and prepare them for use. If they are to be stored empty rather than being reused promptly, the barrels are allowed to dry and sulfur is burned in them to preserve their sanitation. Even with this extensive cleaning, the barrels still carry microbes and contribute to the fermentation of subsequent batches of lambic<ref name='Spitaels et al 2014'>F. Spitaels, A.D. Wieme, M. Janssens, M. Aerts, H.M. Daniel, A. Van Landschoot, L. De Vuyst, P. Vandamme (2014). [[The_Microbial_Diversity_of_Traditional_Spontaneously_Fermented_Lambic_Beer.|The Microbial Diversity of Traditional Spontaneously Fermented Lambic Beer.]] PLOS One, 9(4), e95384.</ref> and only superficial cleaning of barrels can alter the progression of lambic fermentation.<ref name='Spitaels et al 2015'>F. Spitaels, A.D. Wieme, M. Janssens, M. Aerts, H.M. Daniel, A. Van Landschoot, L. De Vuyst, P. Vandamme (2015). The microbial diversity of an industrially produced lambic beer shares members of a traditionally produced one and reveals a core microbiota for lambic beer fermentation. Food Microbiology, 49, 23-32.</ref> | |||
==Turbid mashing== | ==Turbid mashing== | ||
===Introduction and brief history=== | ===Introduction and brief history=== | ||
Lambic production employs a time and labor-intensive mashing process known as turbid mashing. Belgian legal structure in the 1800s favored mashing procedures like turbid mashing as they allowed for a lower water to grain ratio to be used while more effectively extracting carbohydrates from the grain.<ref name='Johnson 1918'/> Turbid mashing involves the removal of mash runnings before the mash is completed. These turbid runnings have not been fully converted in the mash and therefore they contribute complex carbohydrates and proteins to lambic wort which can feed a diverse community of yeast and bacteria during the long lambic fermentation process.<ref name='Guinard'>Jean-Xavier Guinard, [[Books#Classic_Beer_Styles:_Lambic|Classic Beer Styles: Lambic]], 1990.</ref> | Lambic production employs a time and labor-intensive mashing process known as turbid mashing. Belgian legal structure in the 1800s favored mashing procedures like turbid mashing as they allowed for a lower water to grain ratio to be used while more effectively extracting carbohydrates from the grain. <ref name='Johnson 1918'>G.M. Johnson, 1918. A Belgian mashing system suitable for light beers. Journal of the Institute of Brewing. 24(6) 237-251.</ref> Turbid mashing involves the removal of mash runnings before the mash is completed. These turbid runnings have not been fully converted in the mash and therefore they contribute complex carbohydrates and proteins to lambic wort which can feed a diverse community of yeast and bacteria during the long lambic fermentation process.<ref name='Guinard'>Jean-Xavier Guinard, [[Books#Classic_Beer_Styles:_Lambic|Classic Beer Styles: Lambic]], 1990.</ref><ref name='Fix, G.'> Fix, G. Principles of Brewing Science, 2nd Ed, 1999. Brewers Publications, Boulder, Co.</ref> | ||
Although turbid mashing may be beneficial to the specific conditions of lambic fermentation, and lambic is one of the last remaining beers to use this process commercially, the method and similar mashing procedures were used historically for a variety of different beers in Belgium and northern France (e.g. bière de garde<ref name='Evans, 1905>R.E. Evans, 1905. The beer and brewing systems of Northern France. Journal of the Institute of Brewing. 11(3) 223-238.</ref>). Among Belgian beers using turbid mashing were low ABV beers which were not intended for long aging.<ref name='Johnson 1918'/> In comparison to the single infusion system of mashing favored in England, or even multiple step infusion mashes without the removal of turbid wort, Belgian brewers around 1900 felt that turbid mashing resulted in beers with a fuller body and richer flavor development.<ref name='Johnson 1918'/><ref name='Johnson 1895'/> | Although turbid mashing may be beneficial to the specific conditions of lambic fermentation, and lambic is one of the last remaining beers to use this process commercially, the method and similar mashing procedures were used historically for a variety of different beers in Belgium and northern France (e.g. bière de garde<ref name='Evans, 1905>R.E. Evans, 1905. The beer and brewing systems of Northern France. Journal of the Institute of Brewing. 11(3) 223-238.</ref>). Among Belgian beers using turbid mashing were low ABV beers which were not intended for long aging. <ref name='Johnson 1918'>G.M. Johnson, 1918. A Belgian mashing system suitable for light beers. Journal of the Institute of Brewing. 24(6) 237-251.</ref> In comparison to the single infusion system of mashing favored in England, or even multiple step infusion mashes without the removal of turbid wort, Belgian brewers around 1900 felt that turbid mashing resulted in beers with a fuller body and richer flavor development. <ref name='Johnson 1918'>G.M. Johnson, 1918. A Belgian mashing system suitable for light beers. Journal of the Institute of Brewing. 24(6) 237-251.</ref> <ref name='Johnson 1895'>G.M. Johnson, 1895. Brewing in Belgium and Belgian Beers. Journal of the Federated Institutes of Brewing. 1(5) 450-470.</ref> | ||
===Process=== | ===Process=== | ||
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Turbid mashing begins with very a very thick (low water to grain ratio) and cool temperature rest compared to standard mashing. This helps the mash avoid becoming ‘set’ or solidified due to low water to grain ratio and high amount of ungelatinized raw grain traditionally used in lambic breweries.<ref name='Johnson 1918'/> Subsequent rests are achieved by the addition of near boiling water (called infusions) to raise the temperature of the mixture. The exact number of steps and target temperatures of the steps varies among different brewers, but typical steps include a beta glucan rest, a protein rest, multiple saccharification rests and a mash out. These rests are discussed further in the example mash profile below. | Turbid mashing begins with very a very thick (low water to grain ratio) and cool temperature rest compared to standard mashing. This helps the mash avoid becoming ‘set’ or solidified due to low water to grain ratio and high amount of ungelatinized raw grain traditionally used in lambic breweries.<ref name='Johnson 1918'/> Subsequent rests are achieved by the addition of near boiling water (called infusions) to raise the temperature of the mixture. The exact number of steps and target temperatures of the steps varies among different brewers, but typical steps include a beta glucan rest, a protein rest, multiple saccharification rests and a mash out. These rests are discussed further in the example mash profile below. | ||
[[File:Cantillon_draining_mash.jpg|300px|thumb|right|Draining the mash at Cantillon]] | [[File:Cantillon_draining_mash.jpg|300px|thumb|right|Draining turbid wort from the mash at Cantillon]] | ||
Turbid mashing derives its name from the cloudy or turbid wort which is drawn off at specific points during mashing process. This cloudy wort contains starches and proteins which have not been broken down by the enzymes in the mash into fermentable sugars, shorter peptides and amino acids. Turbid wort is transferred to a boiling kettle and heated to near boiling temperatures, denaturing the enzymes present in the liquid and preventing further conversion of starches or proteins. In most lambic breweries this is accomplished in a second boil kettle, but in some more modern breweries (e.g. 3 Fonteinen) where only one kettle is present, the turbid runnings are heated in the single boil kettle. Due to the starch and protein rich nature of this wort, care must be taken with this wort to avoid scorching during heating. In some breweries, kettles for turbid runnings have chains<ref name='Johnson 1918'/><ref name='Johnson 1895'/> or propellers (e.g. Cantillon) to ensure the turbid wort is mixed and does not scorch. In some breweries, especially those using older equipment, the removal or turbid runnings is also necessary to provide sufficient space for additional infusions of water to reach the remaining steps of the mash. | Turbid mashing derives its name from the cloudy or turbid wort which is drawn off at specific points during mashing process. This cloudy wort contains starches and proteins which have not been broken down by the enzymes in the mash into fermentable sugars, shorter peptides and amino acids. Turbid wort is transferred to a boiling kettle and heated to near boiling temperatures, denaturing the enzymes present in the liquid and preventing further conversion of starches or proteins. In most lambic breweries this is accomplished in a second boil kettle, but in some more modern breweries (e.g. 3 Fonteinen) where only one kettle is present, the turbid runnings are heated in the single boil kettle. Due to the starch and protein rich nature of this wort, care must be taken with this wort to avoid scorching during heating. In some breweries, kettles for turbid runnings have chains<ref name='Johnson 1918'/><ref name='Johnson 1895'/> or propellers (e.g. Cantillon) to ensure the turbid wort is mixed and does not scorch. In some breweries, especially those using older equipment, the removal or turbid runnings is also necessary to provide sufficient space for additional infusions of water to reach the remaining steps of the mash. | ||
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[[File:Cantillon_boil_kettle_mixer.jpg|300px|thumb|right|Cantillon's boil kettle with mixer to prevent scorching]] | [[File:Cantillon_boil_kettle_mixer.jpg|300px|thumb|right|Cantillon's boil kettle with mixer to prevent scorching]] | ||
* Extract a portion of turbid liquid from the mash and transfer to a kettle for heating to 80C/176F. | * Extract a portion of turbid liquid from the mash and transfer to a kettle for heating to 80C/176F. | ||
* Add near boiling water to reach a rest temperature of | * Add near boiling water to reach a rest temperature of 65C/149F (saccharification step 1). The enzymes active at this step convert starches in the grain into fermentable sugars. There are two main enzymes active in the saccharification temperature range. At cooler temperatures, such as in this rest, the balance between these two enzymes favors the production of simpler sugars. This temperature is held for a rest of 30 minutes. | ||
* Extract a portion of turbid liquid from the mash and combine with the previous turbid liquid. The mixture is heated to 80C/176F. | * Extract a portion of turbid liquid from the mash and combine with the previous turbid liquid. The mixture is heated to 80C/176F. | ||
* Add near boiling water to reach a rest temperature of 72C/162F and rest for 20 minutes. This temperature also falls into the range of saccharification enzymes. The warmer temperatures of this rest favor the production of intermediate chain length saccharides which may be less fermentable to normal brewer’s yeast but may be accessible to certain bacteria and additional yeast found in lambic fermentations. | * Add near boiling water to reach a rest temperature of 72C/162F and rest for 20 minutes. This temperature also falls into the range of saccharification enzymes. The warmer temperatures of this rest favor the production of intermediate chain length saccharides which may be less fermentable to normal brewer’s yeast but may be accessible to certain bacteria and additional yeast found in lambic fermentations. | ||
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==Boiling== | ==Boiling== | ||
Historically boiling for lambic could have lasted 12 or more hours, but modern practices generally lasts between about 2 hours and 5 hours. Boiling serves a few purposes, including: | |||
*Sterilization of the wort | *Sterilization of the wort | ||
*Extraction of hop antibacterial compounds | [[File:3Fonteinen_coolship.jpg|250px|thumb|right|The split-level, 4 compartment coolship at 3 Fonteinen]] | ||
*Reduction of hop aromatics | *Extraction of hop antibacterial compounds. | ||
*Caramelization of the wort | *Reduction of hop aromatics. The aromatic compounds of hops are volatile and are driven off during the boil. | ||
* | *Caramelization of the wort via to Maillard reactions. | ||
*Reduction of volume. The extensive sparging (rinsing of the grain) during mashing dilutes the sugar content of the pre-boiled wort, and the extended lambic boil helps to concentrate the sugar content. | |||
===Hopping=== | ===Hopping=== | ||
Boiling is also when hops are added. The brewer will make a hop addition as the kettles are being filled, before the wort actually begins to boil. Other than being aged, the | Boiling is also when hops are added. The brewer will make a hop addition as the kettles are being filled, before the wort actually begins to boil. Other than being aged, there is a lot of room for variability in lambic hopping among producers. Hops grown in Belgium, the Czech Republic, Germany, the UK and North America are used (note that many modern Belgian grown hops are varieties which originated in the UK). It is important to use hops with low alpha acid content as brewers are not looking for bitterness or acid contents; only the antimicrobial properties contained within the hop. | ||
==Cooling and Inoculation== | ==Cooling and Inoculation== | ||
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==Fermentation== | ==Fermentation== | ||
[[File:Tilquin_barrel_blowoffs.jpg|250px|thumb|right|Fermenting lambic with overflow tubes at Gueuzerie Tilquin, winter 13-14]] | |||
===Initial Fermentation=== | ===Initial Fermentation=== | ||
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==Fruiting== | ==Fruiting== | ||
===Fruit Selection/Preparation=== | ===Fruit Selection/Preparation=== | ||
The most commonly used fruits in lambic production are cherries (Kriek) and raspberry (Framboise, Framboos). Many other fruits have been experimented with in the beers discussed on this site. Examples include plums, blueberries, gooseberries, apricots, currant, strawberries | The most commonly used fruits in lambic production are cherries (Kriek) and raspberry (Framboise, Framboos). Many other fruits have been experimented with in the beers discussed on this site. Examples include plums, blueberries, gooseberries, apricots, currant, strawberries, apple, banana, and a variety of wine grapes. Traditionally whole fresh fruit was steeped in lambic of minimum one year but many brewers use frozen fruit or fruit extracts/juices in their modern processes. | ||
===Duration=== | ===Duration=== | ||
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Bottles are left unlabeled until time for sale. They are left for a minimum of three months, though most blenders prefer to age their bottles for minimum six months before sale, especially in the case of geuze. This will allow bottle conditioning to occur, and allow the beer to work through phases of viscosity that may occur (Pediococcus byproducts known as 'ropiness'). | Bottles are left unlabeled until time for sale. They are left for a minimum of three months, though most blenders prefer to age their bottles for minimum six months before sale, especially in the case of geuze. This will allow bottle conditioning to occur, and allow the beer to work through phases of viscosity that may occur (Pediococcus byproducts known as 'ropiness'). | ||
== Videos == | |||
<youtube width="250" height="200">p8QOvif4r8o</youtube> | |||
<youtube width="250" height="200">YDGHL_p7ELs</youtube> | |||
==References== | ==References== | ||