You've heard me say that Göller naturally carbonates their beer, but how do they do it? Let me first remind you that following Reinheitsgebot (German Purity Laws) means that Göller adds nothing to their beer besides the big four: water, barley, hops and yeast (add a fifth in the case of wheat ales). This means they will not add CO2 to the bottles, nor do they condition the bottles by adding a little sugar to induce more fermentation. All the bubbles you find in a Göller beer are from the original fermentation! The trick is a combination of technology that keeps the CO2 inside. First, the fermentation tanks are hermetically sealed to prevent any unauthorized transfer of gases. Of course, the pressures would get high enough to explode a tank. Therefore, Göller's fermenter tanks are powerfully built to handle high pressures. Even so, the high pressures would still cause excessive effervescence in the final product. To avoid this, the Germans invented the "spund" valve system that releases any pressure greater than the desired amount. This neat little system gives very precise control over carbonation levels without needing to add any later on.
Are there any advantages to natural carbonation? Tons! First of all, the sealed tanks results in a high pressure fermentation. This means a natural suppression of some of the more volatile compounds that produce off-tasting esters. In other words, it helps create a cleaner, more balanced beer. Secondly, the naturally occurring CO2 bubbles are smaller and better integrated in the liquid, giving you a creamy mouthfeel. This natural carbonation also helps generate that consistent bubble size in good German craft beer, as seen in the fine head at the top of your glass. Here you see one more little detail that makes a huge difference! This is why I love Brauerei Göller!