Por Kevin Szot
En el artículo anterior, vimos la importancia del agua utilizada en la cervecería para determinar el sabor de una cerveza. Mencionamos además la facilidad con que se puede modificar este “ingrediente” para que sea más fiel al agua que dio origen al estilo, agregando minerales para obtener agua muy dura como algunas ales inglesas o reduciendo dureza para elaborar una pilsener. Un efecto de “terroir” del agua.
En una cervecería muy chica, como es el caso de las “artesanales” que todavía son muy caseras, el factor “mano del chef” es relevante. Pero a medida que la empresa crece y se profesionaliza (contando con recetas y sabores definidos, empleando a más de un cervecero y varios asistentes), lo que más se busca obtener es consistencia: que una botella cualquiera se asemeje lo más posible a las otras producciones, sin importar qué mano estaba a cargo de la producción. A fin de cuentas, hacer cerveza en forma profesional es seguir una receta y tener una mentalidad de obsesivo compulsivo para producir siempre el mismo producto. La creatividad viene al sacar una variedad nueva, pero de allí en adelante el desafío pasa a ser repetirlo cada vez. En la bodega uno espera que dos cerveceros distintos logren el mismo resultado si usan la misma receta, los mismos equipos y si siguen fielmente los mismos procesos. No es que sea fácil lograr eso… (versión completa en edición impresa)
Terroir of brewing equipment
In our previous article we saw how important water can be in determining a beer’s flavor. We also mentioned how easy it is to modify this “ingredient” so that is more in tune with the waters where the style originated, by adding more minerals to make a harder water like the English ales, or reducing hardness to make a pilsener. This is somewhat similar to replicating a water’s “terroir”.
In a small craft brewery, such as in the case of those that are closer to homebrew than microbrewery status, the “chef’s hand” is still relevant. However, as the company grows and becomes more professional (with established recipes and well-defined flavor profiles, employing more than one brewer and several assistants) one looks towards obtaining consistency: that any one bottle chosen at random be as similar as possible to any other production of the same variety. It should not matter which person was in charge of production that day. A professional brewer will follow the recipes and is obsessive-compulsive about always replicating the same product. One expects two different brewers to brew the same beer if they use the same recipe on the same equipment and faithfully follow the same processes. Not that it’s easy…
The equipment used in the brewery can also have a big influence in the final flavor of the beer. This was made clear to me when I visited Lagunitas, one of my favorite US breweries, in Petaluma, California, several years ago. The brewery was automated, controlled by software that supposedly cost more to buy and implement than the tanks and other equipment. A computer handled everything, from grinding the grain, activating the pumps and valves, etc. It seemed that the only manual task the brewer had was to add minerals to the water prior to the mash (and only after being instructed to do so by the computer). The brewer had no trouble in showing me his recipes. Quite different from many microbreweries in Chile, he didn’t seem to care if I knew what hops he was using. He told me, “You can’t make my beer, you don’t have my equipment”.
There are indeed many variations in brewery equipment that contribute to a beer’s flavors and identify one brewery versus others. Let’s look at the boil and fermentation.
It is important to obtain a good boil of the wort, as this reduces certain components that leave with the steam (for example DMS, Dimethyl Sulfite) and meld the malty sweetness with the hop bitterness. The boil can be obtained several ways. The simplest is to mount the boil kettle over some big gas burners. This is like a super-sized pot over the kitchen stove. There are craft breweries in Chile that boil more than 1000 liters at time in this fashion. The intense heat of the gas flame can tend to caramelize the wort sugars more than other boiling methods. There are breweries that use jacketed tanks to circulate water under pressure (approximately 102° C) or steam to obtain the boil. At this lower temperature you don’t get the same degree of caramelization of the sugars, so the final flavor will end up different compared to the direct flame. Technology is important here too. Kuntsmann brewery in Valdivia has a new boil system from the German Schülz company, where the “boil” is done in a column that has a vacuum. This permits them to boil at less than 100° C, thus avoiding the caramelization and supposedly reducing the production of DMS.
Of course one can also go to the other extreme: consider the “Stein Beer” process (“stein” is German for ‘stone’). This is an ancient way to boil wort inside a wooden container. Special stones are heated on coals, then added to the wort to reach and maintain the boil. It must be spectacular to see the steam and hear the sound of the rocks hitting the wort (these rocks don’t break with the heat shock) – but this will increase the effecting of crystalizing sugars on the rocks while they are in the wort.
There are many variations and possible configurations for the fermentation tanks, all of which can impact the beer’s flavor. Fermenting in a small 300 liter tank will not give the same beer as that of a 3.000 or even 30.000 liter tank. The fermenters that are very tall in relation to their width produce more movement of CO2 since the gas has to climb higher, generating more natural movement of the beer than in a tank with a wider diameter. Tall tanks can also have more temperature variations within the fermenter, which means that the beer in the top can taste different than that at the bottom. One can also choose to ferment with the tank at atmospheric pressure, or opt to maintain the beer under CO2 pressure. Each technique will give different flavors to the final product and must be used each time by the brewery during fermentations in order to achieve consistency between different batches.
It is important for a brewery to control its processes as consistently as possible, and learn to take advantage of its equipment “terroir” to help differentiate it from other producers.
