Brewing Belgian-Style Beers: Tips from the Pros
Belgian-style beers are a difficult breed to put your brewing thumb on. For one, the array of ingredients and resulting flavors vary widely across the spectrum, making for an even wider array of actual Belgian beer styles. One consistent attribute across the board with Belgian brewing is the distinctive utilization of yeast as a flavor contributor. In fact, some would argue that yeast is the foremost flavor indicator, moreso than malt or hops. Take it from the pros!
Brewer: Randy Thiel, Brewery Ommegang in Cooperstown, NY
Yeast plays a primary role in the flavor profile of most Belgian beers. The flavor peculiarities of specific strains are allowed to take center stage by keeping a leash on other ingredients — that is, keeping a balance on hop, malt and spice contributions allows the impact of the yeast to be noticed. Beyond full attenuation of the wort, the aspect that most brewers look at with these yeasts is the quality and quantity of ester formation.
Depending on the yeast, this can be affected by pitching rates, fermentation temperature, yeast health and level of oxygen (i.e. aeration) at the start of fermentation. These are all very strain-specific parameters and, as such, a technique utilized for one strain may have a completely different effect on a different strain. So embrace the creative joy of homebrewing and start experimenting!
Temperature and inoculation techniques have a big impact on your resulting artwork, mostly with regard to ester formation. Most of the literature suggests that any parameter that forces faster and more quantitative growth of yeast will also increase ester production. Higher fermentation temps and low pitching rates would fit into this scheme. But, this seems a bit too simplistic. Often, these same parameters have a direct effect on fusel alcohol formation, which should be kept to a minimum.
Since fermentations are very complex reactions that have numerous interactive variables (more than can be quantified!) the best approach is to experiment with specific strains, temperatures and yeast pitching rates. The truth is that “your mileage may vary” with your particular brewing, fermentation and bottling techniques. Get to know your artistic media (in this case, your brew system and ingredients) and tweak it accordingly to suit your muse.
Brewer: Rob Tod, Allagash Brewing in Portland, ME
For us at Allagash, the key ingredient to obtaining the “traditional” Belgian character is the yeast strain used. This is a generalization, but if you were to brew any of our beers with a “non-Belgian” yeast strain, the beers would not have the classic Belgian character. However, if you were to brew a beer with a British bitter recipe, and ferment it with a Belgian yeast, it would taste distinctively Belgian. So yes, I would agree that despite the importance of an appropriate malt and hops bill, the yeast strain is the most critical factor in the overall flavor profile.
All of that being said, we are very careful about our malt and hops bill, and we try to make sure that the final beer is complex and balanced. The two really go hand-in-hand, if the beer is balanced, more of the subtle yeast, malt and hop characters are able to express themselves.
As a generalization (and there are exceptions to this with some of the beers we brew), we find our beers are better balanced with conservative amounts of the sweeter and roasted malts, and the use of the “less-bitter” or noble hop varieties. Sometimes the beers with the simplest malt and hops bills are the most complex beers after fermentation and conditioning.
If you are seeking more consistent results, I would recommend starting with a purchased yeast strain. By going this route, you know what you are getting, and you have more reassurance that your hard work in brewing the beer is going to yield good results. Again, make sure to get temperature ratings, and also, if you are brewing a high gravity beer, make sure that the yeast strain has good alcohol tolerance.
Brewer: Steven Pauwels, Boulevard Brewing Company in Kansas City, MO
Malt and hops might be a less determining factor in the final flavor of a brew, but they are important for the overall flavor profile of a Belgian-style beer. Traditionally no (or very low amounts of) roasted malts and only noble hops are used to pronounce the flavor contribution from the yeast. Nowadays there are some great examples that use American hops.
As for yeast, 1 million cells per mL per ºPlato is commonly used as rule of thumb. Some brewers use only one third this amount, while others use up to three times the amount. This depends on your wort aeration, amount of trub in your wort, percentage sugar and of course the yeast strain.
Important is the ratio between higher alcohols and esters. It is essential to control the fermentation temperature during the first half to 2/3 of the fermentation to reduce the higher alcohols. Pitch the wort at a low temperature (64 ºF or 18 ºC). Also, a lot of Belgian yeast strains are very temperature sensitive and will stop working when the temperature difference between cooling liquid and fermentation temperature is too high.
Personally, I have never been able to culture yeast from a bottle. Maybe if you can find a very fresh bottle you might be able to. Attenuation is by far the most important spec that you need to keep in mind whether purchasing or culturing yeast. Belgian beers are dry. They might taste sweet and full, but that perception is usually from the alcohol. The Belgian style beers we brew at Boulevard have a higher attenuation than our pale ale for example. Also, follow the temperature recommendations. Most yeast strains make the best beers over 80 ºF (27 ºC), others should not go higher than 77 ºF (25 ºC).
Use healthy yeast. Kick start your yeast by putting it into a starter a couple of hours before pitching. With some of our yeasts we will add twice the yeast volume of wort (or sugar water less than 6 ºPlato) to get the yeast active.
This will guarantee a rigorous fermentation and a nice ester profile. Spices can also help make the flavor profile of your beer more complex if dosed in such a quantity that it does not overwhelm.
