Difference between revisions of "Culture vs. Chemistry"
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| − | + | [[File:LambicInfoDragon.png|right|375px]] | |
| − | One of the most common debates surrounding | + | [[An_Overview_of_Lambic|← An Overview of Lambic]] |
| + | ==Culture vs. Chemistry== | ||
| + | One of the most common debates surrounding lambic today is whether or not lambic can be produced outside of the Pajottenland. This is not a simple question as there is no clear right or wrong answer. This write-up attempts to document the information regarding this issue. Minimally, there are four areas that impact this topic: terroir, process, regulations, and culture. | ||
| − | + | ===Terroir=== | |
| − | |||
| − | |||
| − | |||
| − | |||
| − | + | Is it possible to create a finished product, outside of the Pajottenland or the country of Belgium, which is biochemically indistinguishable from traditional lambic? | |
| − | + | Through the late 1800s, people assumed that the right combination of wild yeasts for lambic only existed in the Pajottenland. Technically, in 1904, Danish brewing scientist Niels Kjelte Claussen discovered the first brettanomyces in an English beer. He presented his findings to the British Beer & Pub Association and later published them in the Journal of the Institute of Brewing. Because he found these yeasts in British beers, he chose the name “brittanomyces” (the Greek word for “British fungus”). However, a typesetter’s error changed this to “brettanomyces,” with an ''e''.<ref name=GeuzeKriek>Jef Van den Steen, [[Books#Geuze & Kriek: The Secret of lambic Beer|Geuze & Kriek: The Secret of Lambic Beer]], 2012</ref> | |
| − | + | In spite of brettanomyces existing worldwide, it is still reasonable to assume that the combination and ratio of brettanomyces and other individual microorganisms within the Pajottenland are unique to the local terroir. For example, in 1993, Frank Boon was said to have discovered 86 unique strains that he believed played a significant role in the fermentation at [[Brouwerij_Boon|Boon]].<ref name=Lambic.digest-9312>Lambic Digest, December 2, 1993, http://lambic.info/lambic_digest/1993/9312.txt</ref> | |
| − | + | However, the naturally occurring yeasts at Boon are significantly different than yeasts occurring at Cantillon, for example. Even the yeasts at an individual location will change over time. Cantillon is now surrounded by buildings, cars, and industry. As cityscapes change so does the local terroir. The yeasts of 50 years ago at any location are likely different than the yeasts of today. Even the yeasts and other microflora at other locations around the world have similar characteristics. Studies have shown that yeasts in other regions, such as the Allagash Brewery in Maine, have a similar makeup.<ref name=AWAStudy> Brewhouse-Resident Microbiota Are Responsible for Multi-Stage Fermentation of American Coolship Ale, http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0035507</ref> | |
| − | + | While the yeast may not be tied to the Pajottenland, the term lambic is. Lambic is traditionally a beer that has been spontaneously fermented in the Pajottenland. As [[An Overview of Lambic#History|history]] shows, this term and its regional use goes back hundreds of years. Other regions continue to develop terms, largely based on lambic, to identify the spontaneous fermentation that occurs in their local terroir (Sonambic at Russian River in California, Colorambic at AC Golden in Colorado). These naming designations help define the regional geography, culture, and experimentation occurring in their area. Belgian breweries and other breweries around the world do not always follow this designation however. For example: | |
| − | + | * Belgian breweries outside of the Pajottenland spontaneously ferment a small portion of their beer within the Pajottenland and the remainder from another region. Given some of the legal definitions created later in this article, this does make the beer technically lambic, however it does not meet the cultural intent. | |
| + | * Many international breweries are naming beers lambic by either using an artificially pitched small subset of the overall microorganisms found in the Pajottenland, or by doing their own regional spontaneous fermentation but failing to designate it in a unique way. | ||
| − | + | Finally, it is important to acknowledge that while in today’s day and age, it is possible for brewers, with more developed scientific techniques, to replicate the ratios and quantities of the various strains of Brettanomyces and other microorganisms outside of the Pajottenland. However, this would require significant study to replicate those regional microorganisms that affect the beer throughout the process, as opposed to just those that are present in the bottle in the later phases of fermentation. It would require discipline and a strong traditional focus without significant deviation or experimentation. And if these organisms were produced under laboratory-controlled conditions rather than spontaneously obtained, is it really lambic? | |
| − | |||
| − | |||
| − | + | ===Process=== | |
| − | + | Lambic is much more than the yeasts themselves. The [[Brewing Lambic|brewing process]] for lambic was regionally developed over hundreds of years and is specifically focused on creating the appropriate enzymes and nutrients for the wild yeasts to thrive and evolve the beer over multiple years. No other beer in the world is produced using a similar process. | |
| − | |||
| − | Lambic is much more than the yeasts themselves. The [[Brewing Lambic|brewing process]] for | ||
*The unique turbid mash brewing process, designed to develop proteins and amino acids that protect against oxidation and acid formation | *The unique turbid mash brewing process, designed to develop proteins and amino acids that protect against oxidation and acid formation | ||
| − | *An extended boil, creating a wort where only certain micro-organisms can survive <ref name= | + | *An extended boil, creating a wort where only certain micro-organisms can survive.<ref name=GeuzeKriek /> |
| − | *A limited brewing season controlled by seasonal temperatures to limit mold growth, | + | *A limited brewing season controlled by seasonal temperatures to limit mold growth, acetic characteristics, and microorganisms that thrive in higher temperatures but negatively impact the beer |
| − | *The use of a koelschip and other regionally developed spontaneous fermentation processes to expose the wort with the open air and regional microflora | + | *The use of a [[koelschip]] and other regionally developed spontaneous fermentation processes to expose the wort with the open air and regional microflora |
*Fermentation in wooden barrels, ripe with wild yeast | *Fermentation in wooden barrels, ripe with wild yeast | ||
*The terroir of the building itself, from the ceiling to the floor as well as the local surroundings | *The terroir of the building itself, from the ceiling to the floor as well as the local surroundings | ||
*A complex aging process, in which the different wild yeasts impact the liquid uniquely at multiple phases of the beer’s development | *A complex aging process, in which the different wild yeasts impact the liquid uniquely at multiple phases of the beer’s development | ||
| − | *A blending process involving multiple barrels of | + | *A blending process involving multiple barrels of lambic, often from multiple years, to create a complex product capable of extended maturation. |
| − | |||
| − | |||
| − | + | This process is as much a tradition as a recipe. It is passed down from generation to generation as can be seen throughout the brewery histories described throughout this site. Lambic brewing requires patience and structure, and does not lend itself to experimentation (at least during the brewing process…many lambic brewers and blenders experiment during blending). | |
| − | + | The entire process is needed to make lambic that can age gracefully and continue to develop as the microorganisms work through their various phases. It is certainly possible that spontaneously fermented beers following these processes can be produced anywhere, capturing the yeasts that are local to that geography. Jeff Sparrow reminisces in [[Books#Wild_Brews:_Culture_and_Craftsmanship_in_the_Belgian_Tradition|''Wild Brews: Culture and Craftsmanship in the Belgian Tradition'']] of a conversation that he had with Jean-Pierre Van Roy: | |
| − | + | :: ''“But don’t despair; believe it or not, you can spontaneously ferment beer anywhere in the world. Jean-Pierre Van Roy of the Cantillon brewery in Brussels told me so on my first visit. I just didn’t know what to make of the statement at the time. Since then, Van Roy’s revelation has become a great deal clearer. Van Roy told me you must develop a taste for your own local lambic, although he never had to taste one result of his suggestion.”''<ref name=“WildBrews”>Jeff Sparrow, [[Books#Wild Brews: Culture and Craftsmanship in the Belgian Tradition|Wild Brews: Culture and Craftsmanship in the Belgian Tradition]], 2005</ref> | |
| − | + | Despite the recent rise in the use of koelschips and spontaneous fermentation outside of Belgium, there is still significant variation in the processes and techniques used to produce a wide variety of new wild beers in other regions. These spontaneously fermented wild ales may have been brewed at a different time of the year, they may or may not have been brewed with a process designed to create nutrients for long-term yeast interaction, or they may have significant variations to the brewing process and techniques that yield a different outcome. Each brewing decision, along with the regional terroir and microflora, help define that regional wild ale. | |
| − | + | Finally, it is important to acknowledge that confusion and inconsistency over the brewing process of beers called lambic exists within Belgium as well. Many Belgian brewers are creating a product with only minimal lambic (there is no limit to how little lambic must be in a beer in Belgium to be called lambic) and blending in other beer, juices, or adjuncts. | |
| + | ===Regulation=== | ||
Naturally, Belgian brewers and lawmakers have wanted to protect and preserve their indigenous product. Lambic has, like many other popular regional products throughout Europe, been regionally protected through law and decree. | Naturally, Belgian brewers and lawmakers have wanted to protect and preserve their indigenous product. Lambic has, like many other popular regional products throughout Europe, been regionally protected through law and decree. | ||
| − | * The first attempts to protect | + | * The first attempts to protect lambic date back to 1930.<ref name=TFP>Teresa de Noronha Vaz, [http://www.amazon.com/Traditional-Production-Sustainable-Development-Geography/dp/0754674622/ref=sr_1_1?s=books&ie=UTF8&qid=1410234809&sr=1-1 Traditional Food Production and Rural Sustainable Development (Ashgate Economic Geography Series)], 1998</ref> |
| − | * In 1965, the Belgian government imposed restrictions on the use of the names Lambic, Geuze, and Kriek requiring spontaneous fermentation and the use of specific raw materials. <ref name=TFP>Teresa de Noronha Vaz, [http://www.amazon.com/Traditional-Production-Sustainable-Development-Geography/dp/0754674622/ref=sr_1_1?s=books&ie=UTF8&qid=1410234809&sr=1-1 Traditional Food Production and Rural Sustainable Development (Ashgate Economic Geography Series)], 1998</ref> | + | * In 1965, the Belgian government imposed restrictions on the use of the names Lambic, Geuze, and Kriek requiring spontaneous fermentation and the use of specific raw materials.<ref name=TFP>Teresa de Noronha Vaz, [http://www.amazon.com/Traditional-Production-Sustainable-Development-Geography/dp/0754674622/ref=sr_1_1?s=books&ie=UTF8&qid=1410234809&sr=1-1 Traditional Food Production and Rural Sustainable Development (Ashgate Economic Geography Series)], 1998</ref> This decree was abolished in 1993. |
| − | * In 1993, a new royal decree was put in place. This decree specified that spontaneous fermentation must be part of the process and that wheat must be 30% of the grain bill. However, it did not specify how much of the beer needed to be | + | * In 1993, a new royal decree was put in place. This decree specified that spontaneous fermentation must be part of the process and that wheat must be 30% of the grain bill. However, it did not specify how much of the beer needed to be lambic in order to carry the lambic name or specify any regional protections. |
| − | * In 1997, five | + | * In 1997, five lambic related products were protected by being granted Traditional Specialty Guaranteed (“TSG”) status. Within Europe, TSG protects the brewing style, however it again does not tie the beer specifically to a region. |
| − | * Since 2004, brewers of | + | * Since 2004, brewers of lambic can also apply for a regional label indicating that it is regional and traditional.<ref name=streekproduct>http://www.streekproduct.be</ref> |
| − | These laws, while an honest attempt to protect | + | These laws, while an honest attempt to protect lambic, did not accomplish the intended goal. Because there were so many competing interests, even among the traditional lambic producers, these resulting laws and decrees had many gaps. First, there was no regional protection. Second, there was no definition surrounding the term lambic regarding issues like how much of a beer must be spontaneously fermented, or if artificial sweeteners or syrups could be used, or other issues. |
While these laws and decrees did not achieve the goals of protecting lambic, that was certainly their intent. A lack of specificity and enforceability in these laws does not indicate that instead, the legal bodies are endorsing non-traditional beers as lambic. | While these laws and decrees did not achieve the goals of protecting lambic, that was certainly their intent. A lack of specificity and enforceability in these laws does not indicate that instead, the legal bodies are endorsing non-traditional beers as lambic. | ||
| − | ==Culture== | + | ===Culture=== |
| − | One of the most unique aspects of | + | One of the most unique aspects of lambic in Belgium is its [[An Overview of Lambic#History|history]] and culture. It makes sense that the regional brewers have striven to protect this. At the same time, given the success of lambic, it is also not surprising that many breweries, both in Belgium and the rest of the world, have sought to capitalize on the name. |
| − | From a cultural perspective, can | + | From a cultural perspective, can lambic be replicated? Lambic represents: |
* Hundreds of years of history | * Hundreds of years of history | ||
* A culture that identified the unique natural characteristics of a region and leveraged this terroir to produce a product unlike any other | * A culture that identified the unique natural characteristics of a region and leveraged this terroir to produce a product unlike any other | ||
| Line 69: | Line 63: | ||
* Family brewers and blenders | * Family brewers and blenders | ||
* Hundreds of regional breweries that have come and gone, | * Hundreds of regional breweries that have come and gone, | ||
| − | * A culture where café blenders would buy wort and create their own | + | * A culture where café blenders would buy wort and create their own lambic |
| − | * An annual pilgrimage of beer geeks worldwide who journey to Belgium to experience | + | * An annual pilgrimage of beer geeks worldwide who journey to Belgium to experience lambic |
| − | There is no other beer like this in the world, where every characteristic of the brewing, blending, aging and serving | + | There is no other beer like this in the world, where every characteristic of the brewing, blending, aging and serving process is completely unique. While the lambic style is regularly imitated, minimized, and commercialized, there is nothing outside of lambic brewed traditionally in the Pajottenland that can truly capture what lambic represents. |
==Summary== | ==Summary== | ||
| − | Brewers are ingenious. They have and will continue to brew wild ales in other regions, either through the use of that region’s local terroir or through chemistry and microbiology. They will follow many of the steps described above that are unique to | + | Brewers are ingenious. They have and will continue to brew wild ales in other regions, either through the use of that region’s local terroir or through chemistry and microbiology. They will follow many of the steps described above that are unique to lambic. And beyond that, they will experiment and make their own beers, changing the process to create their own unique beverages. Experimentation is good and should be encouraged. We do hope however, that brewers truly attempting to create a Belgian style lambic respect this amazing style, create a product that can stand the test of time, and strive to brew a complex beer that is much more than just “sour” or “funky”. We hope that they respect the regional history of the Belgian lambic itself, and instead make their own wild ales, indigenous to their own region, brewery and history. |
| − | Ultimately, | + | Ultimately, it is up to the consumer to know what they are drinking, to understand the ingredients and the brewing process. The name lambic will continue to be capitalized on and exploited; there will continue to be non-traditional beers released that incorrectly use this name. There will be people who argue with the point of view presented here or try to shape the argument in their favor for capitalistic gain. |
| − | Ask questions. Learn more. Understand the ingredients of the beer that | + | Ask questions. Learn more. Understand the ingredients of the beer that you are drinking. Use this wiki and the other lambic [[Home#Learn_More|resources]] referenced to educate yourself. |
== References == | == References == | ||
<references /> | <references /> | ||
Latest revision as of 16:08, 19 February 2017
Contents
Culture vs. Chemistry
One of the most common debates surrounding lambic today is whether or not lambic can be produced outside of the Pajottenland. This is not a simple question as there is no clear right or wrong answer. This write-up attempts to document the information regarding this issue. Minimally, there are four areas that impact this topic: terroir, process, regulations, and culture.
Terroir
Is it possible to create a finished product, outside of the Pajottenland or the country of Belgium, which is biochemically indistinguishable from traditional lambic?
Through the late 1800s, people assumed that the right combination of wild yeasts for lambic only existed in the Pajottenland. Technically, in 1904, Danish brewing scientist Niels Kjelte Claussen discovered the first brettanomyces in an English beer. He presented his findings to the British Beer & Pub Association and later published them in the Journal of the Institute of Brewing. Because he found these yeasts in British beers, he chose the name “brittanomyces” (the Greek word for “British fungus”). However, a typesetter’s error changed this to “brettanomyces,” with an e.[1]
In spite of brettanomyces existing worldwide, it is still reasonable to assume that the combination and ratio of brettanomyces and other individual microorganisms within the Pajottenland are unique to the local terroir. For example, in 1993, Frank Boon was said to have discovered 86 unique strains that he believed played a significant role in the fermentation at Boon.[2]
However, the naturally occurring yeasts at Boon are significantly different than yeasts occurring at Cantillon, for example. Even the yeasts at an individual location will change over time. Cantillon is now surrounded by buildings, cars, and industry. As cityscapes change so does the local terroir. The yeasts of 50 years ago at any location are likely different than the yeasts of today. Even the yeasts and other microflora at other locations around the world have similar characteristics. Studies have shown that yeasts in other regions, such as the Allagash Brewery in Maine, have a similar makeup.[3]
While the yeast may not be tied to the Pajottenland, the term lambic is. Lambic is traditionally a beer that has been spontaneously fermented in the Pajottenland. As history shows, this term and its regional use goes back hundreds of years. Other regions continue to develop terms, largely based on lambic, to identify the spontaneous fermentation that occurs in their local terroir (Sonambic at Russian River in California, Colorambic at AC Golden in Colorado). These naming designations help define the regional geography, culture, and experimentation occurring in their area. Belgian breweries and other breweries around the world do not always follow this designation however. For example:
- Belgian breweries outside of the Pajottenland spontaneously ferment a small portion of their beer within the Pajottenland and the remainder from another region. Given some of the legal definitions created later in this article, this does make the beer technically lambic, however it does not meet the cultural intent.
- Many international breweries are naming beers lambic by either using an artificially pitched small subset of the overall microorganisms found in the Pajottenland, or by doing their own regional spontaneous fermentation but failing to designate it in a unique way.
Finally, it is important to acknowledge that while in today’s day and age, it is possible for brewers, with more developed scientific techniques, to replicate the ratios and quantities of the various strains of Brettanomyces and other microorganisms outside of the Pajottenland. However, this would require significant study to replicate those regional microorganisms that affect the beer throughout the process, as opposed to just those that are present in the bottle in the later phases of fermentation. It would require discipline and a strong traditional focus without significant deviation or experimentation. And if these organisms were produced under laboratory-controlled conditions rather than spontaneously obtained, is it really lambic?
Process
Lambic is much more than the yeasts themselves. The brewing process for lambic was regionally developed over hundreds of years and is specifically focused on creating the appropriate enzymes and nutrients for the wild yeasts to thrive and evolve the beer over multiple years. No other beer in the world is produced using a similar process.
- The unique turbid mash brewing process, designed to develop proteins and amino acids that protect against oxidation and acid formation
- An extended boil, creating a wort where only certain micro-organisms can survive.[1]
- A limited brewing season controlled by seasonal temperatures to limit mold growth, acetic characteristics, and microorganisms that thrive in higher temperatures but negatively impact the beer
- The use of a koelschip and other regionally developed spontaneous fermentation processes to expose the wort with the open air and regional microflora
- Fermentation in wooden barrels, ripe with wild yeast
- The terroir of the building itself, from the ceiling to the floor as well as the local surroundings
- A complex aging process, in which the different wild yeasts impact the liquid uniquely at multiple phases of the beer’s development
- A blending process involving multiple barrels of lambic, often from multiple years, to create a complex product capable of extended maturation.
This process is as much a tradition as a recipe. It is passed down from generation to generation as can be seen throughout the brewery histories described throughout this site. Lambic brewing requires patience and structure, and does not lend itself to experimentation (at least during the brewing process…many lambic brewers and blenders experiment during blending).
The entire process is needed to make lambic that can age gracefully and continue to develop as the microorganisms work through their various phases. It is certainly possible that spontaneously fermented beers following these processes can be produced anywhere, capturing the yeasts that are local to that geography. Jeff Sparrow reminisces in Wild Brews: Culture and Craftsmanship in the Belgian Tradition of a conversation that he had with Jean-Pierre Van Roy:
- “But don’t despair; believe it or not, you can spontaneously ferment beer anywhere in the world. Jean-Pierre Van Roy of the Cantillon brewery in Brussels told me so on my first visit. I just didn’t know what to make of the statement at the time. Since then, Van Roy’s revelation has become a great deal clearer. Van Roy told me you must develop a taste for your own local lambic, although he never had to taste one result of his suggestion.”[4]
Despite the recent rise in the use of koelschips and spontaneous fermentation outside of Belgium, there is still significant variation in the processes and techniques used to produce a wide variety of new wild beers in other regions. These spontaneously fermented wild ales may have been brewed at a different time of the year, they may or may not have been brewed with a process designed to create nutrients for long-term yeast interaction, or they may have significant variations to the brewing process and techniques that yield a different outcome. Each brewing decision, along with the regional terroir and microflora, help define that regional wild ale.
Finally, it is important to acknowledge that confusion and inconsistency over the brewing process of beers called lambic exists within Belgium as well. Many Belgian brewers are creating a product with only minimal lambic (there is no limit to how little lambic must be in a beer in Belgium to be called lambic) and blending in other beer, juices, or adjuncts.
Regulation
Naturally, Belgian brewers and lawmakers have wanted to protect and preserve their indigenous product. Lambic has, like many other popular regional products throughout Europe, been regionally protected through law and decree.
- The first attempts to protect lambic date back to 1930.[5]
- In 1965, the Belgian government imposed restrictions on the use of the names Lambic, Geuze, and Kriek requiring spontaneous fermentation and the use of specific raw materials.[5] This decree was abolished in 1993.
- In 1993, a new royal decree was put in place. This decree specified that spontaneous fermentation must be part of the process and that wheat must be 30% of the grain bill. However, it did not specify how much of the beer needed to be lambic in order to carry the lambic name or specify any regional protections.
- In 1997, five lambic related products were protected by being granted Traditional Specialty Guaranteed (“TSG”) status. Within Europe, TSG protects the brewing style, however it again does not tie the beer specifically to a region.
- Since 2004, brewers of lambic can also apply for a regional label indicating that it is regional and traditional.[6]
These laws, while an honest attempt to protect lambic, did not accomplish the intended goal. Because there were so many competing interests, even among the traditional lambic producers, these resulting laws and decrees had many gaps. First, there was no regional protection. Second, there was no definition surrounding the term lambic regarding issues like how much of a beer must be spontaneously fermented, or if artificial sweeteners or syrups could be used, or other issues.
While these laws and decrees did not achieve the goals of protecting lambic, that was certainly their intent. A lack of specificity and enforceability in these laws does not indicate that instead, the legal bodies are endorsing non-traditional beers as lambic.
Culture
One of the most unique aspects of lambic in Belgium is its history and culture. It makes sense that the regional brewers have striven to protect this. At the same time, given the success of lambic, it is also not surprising that many breweries, both in Belgium and the rest of the world, have sought to capitalize on the name.
From a cultural perspective, can lambic be replicated? Lambic represents:
- Hundreds of years of history
- A culture that identified the unique natural characteristics of a region and leveraged this terroir to produce a product unlike any other
- A unique localized brewing style where each step was developed specifically to capture and enhance the effects of the region
- Family brewers and blenders
- Hundreds of regional breweries that have come and gone,
- A culture where café blenders would buy wort and create their own lambic
- An annual pilgrimage of beer geeks worldwide who journey to Belgium to experience lambic
There is no other beer like this in the world, where every characteristic of the brewing, blending, aging and serving process is completely unique. While the lambic style is regularly imitated, minimized, and commercialized, there is nothing outside of lambic brewed traditionally in the Pajottenland that can truly capture what lambic represents.
Summary
Brewers are ingenious. They have and will continue to brew wild ales in other regions, either through the use of that region’s local terroir or through chemistry and microbiology. They will follow many of the steps described above that are unique to lambic. And beyond that, they will experiment and make their own beers, changing the process to create their own unique beverages. Experimentation is good and should be encouraged. We do hope however, that brewers truly attempting to create a Belgian style lambic respect this amazing style, create a product that can stand the test of time, and strive to brew a complex beer that is much more than just “sour” or “funky”. We hope that they respect the regional history of the Belgian lambic itself, and instead make their own wild ales, indigenous to their own region, brewery and history.
Ultimately, it is up to the consumer to know what they are drinking, to understand the ingredients and the brewing process. The name lambic will continue to be capitalized on and exploited; there will continue to be non-traditional beers released that incorrectly use this name. There will be people who argue with the point of view presented here or try to shape the argument in their favor for capitalistic gain.
Ask questions. Learn more. Understand the ingredients of the beer that you are drinking. Use this wiki and the other lambic resources referenced to educate yourself.
References
- ↑ 1.0 1.1 Jef Van den Steen, Geuze & Kriek: The Secret of Lambic Beer, 2012
- ↑ Lambic Digest, December 2, 1993, http://lambic.info/lambic_digest/1993/9312.txt
- ↑ Brewhouse-Resident Microbiota Are Responsible for Multi-Stage Fermentation of American Coolship Ale, http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0035507
- ↑ Jeff Sparrow, Wild Brews: Culture and Craftsmanship in the Belgian Tradition, 2005
- ↑ 5.0 5.1 Teresa de Noronha Vaz, Traditional Food Production and Rural Sustainable Development (Ashgate Economic Geography Series), 1998
- ↑ http://www.streekproduct.be