Another Extreme Beer

News broke this week of another entry into the race to create the strongest and most extreme beer on the commercial market. Scottish brewer BrewDog, currently the largest independent brewery in Scotland, recently announced the release of a 32% ABV imperial stout aged in whisky casks quizzically named Tactical Nuclear Penguin.

Aside from bragging rights used in marketing, high-gravity extreme beers are quite an accomplishment and a testament to the skill of a brewer. Alcohol is a toxic substance (hence the root word for intoxication), especially to microorganisms. Even though their entire existence is spent converting sugar to alcohol and carbon dioxide, most yeast strains cannot survive as their environment approaches 10% to 12% alcohol by volume.

So how are such high-gravity beers made? The first step is in the choice of yeast used, and some brewers have developed their own robust yeast strains in their house laboratories. Even so, these specialized species cannot achieve the record-setting levels of 25% ABV or above without a lot of prodding from the brewer.

Such a batch begins with making a very large starter, which is a type of mini-brew used just to increase the cell count of the yeast before introducing it to the wort. Homebrewers will commonly make a starter out of nothing but sugar, yeast and water, allowing it to grow for hours or days before brewing. The greater number of yeast cells that can begin fermentation immediately when introduced forgoes a lot of other problems as well.

The second consideration is to use highly fermentable grains, that is, grains with abundant starch content that can be fully converted and fully attenuated by the yeast. Likewise, fermentation is given another starting boost by highly oxygenating the wort once the yeast has been pitched, generally by agitation or even bubbling pure oxygen through the liquid.

Fermentation will naturally proceed quite vigorously at first and will begin to slow after a certain point, eventually coming to a halt once the consumable sugar content has been depleted. For that reason, brewers of high-gravity beers will continuously make small additions of sugar to feed the yeast and keep it alive and active, sometimes for weeks or months.

Eventually, any ale or lager yeast will reach its limit of survivability as the alcohol levels continue to rise. Thus, brewers will sometimes switch to other strains of yeast in later stages to finish off the fermentation to the target levels. Champagne yeast is a favorite alternative, as it is highly tolerant to alcohol and neutral in flavor.

However, BrewDog used none of these methods in brewing their record-setting beer, instead relying on a bit of a brewing cheat. Although water freezes at 0°C, ethanol does not freeze until −114°C. By freezing the wort after fermentation, the water content will freeze into a solid block of ice that can be easily removed, leaving behind the unfrozen alcohol in a much stronger beverage.

This method of freezing and removing the water is used in producing the German beer style eisbock, strong beers of about 16% ABV so named after this process. BrewDog did not actually brew a 32% beer but instead made a 10% imperial stout that was held at −20°C for three weeks. The result may be the same in the final product but the achievement is far less impressive than actually coaxing and manipulating yeast to perform far beyond their limits.

Is Beer Vegan?

The question was recently raised about whether or not craft beer (or beer in general) can be considered vegan. As people become more conscious about what they eat and where their food comes from, and especially as organic claims and certification more often than not blur the lines of truth and nutrition, this can be a genuine concern to those on restricted diets.

First of all, all beer is clearly a vegetarian foodstuff. Vegetarianism is the abstaining from eating the flesh of all animals, and no meat products are ever used in any brewing process of any kind. (Medieval recipes exist for variations on a rather unappealing brewed beverage known as cock ale, but that is a topic for another day.)

However, modern veganism is much more restrictive than a traditional vegetarian diet. As defined by the American Vegan Society, “[t]he vegan diet excludes flesh, fish, fowl, dairy products (animal milk, butter, cheese, yogurt, etc.), eggs, honey, animal gelatin, and all other foods of animal origin.” This means avoiding not only animal flesh but all animal byproducts and derivatives.

From simply an ingredient standpoint, most beer can be considered wholly vegan. Even the most adventurous craft beers include nothing but malted grains, hops, water, fruit or spice additions, and yeast. (Any beer containing honey obviously cannot be considered vegan.) Yeast itself is classified as a fungus, so although it is an independent microorganism it should offer no objection as mushrooms and tofu are acceptable to the vegan diet.

The point at which some beers may garner the disapproval of vegans lies in the various methods used for clarification of the beverage. Many craft brewers prefer to leave their beers unfiltered as it can enhance body and flavor, so these should offer no objection whatsoever. But an additional clarification step at the end of the brewing process can be problematic, depending on the method used.

One popular method of clarifying beer is the addition of finings near the end of the brewing process. Finings are materials that function as flocculation points for yeast in suspension to collect and eventually sink to the bottom under their own weight, where they can be easily removed in bulk. Even though very little of the fining material remains in the finished product, this practice is enough to render the beer non-vegan if animal byproducts are used.

Specifically, at one time brewers used a material known as isinglass as a fining material. Isinglass is a collagen product obtained from the swim bladders of sturgeon, and it has a few other cooking applications in confectionery and dessert-making. However, many modern brewers are abandoning the use of isinglass in industrial brewing—not over vegan objections but simply due to the expense, as the material has become quite costly.

Another fining material very popular with homebrewers is known as Irish moss. Irish moss is a red algae containing carrageenan that looks much like any other herb when dried, and is of course wholly vegan. Other fining substances such as gelatin from fats, casein from cheesemaking or albumen from chicken eggs are so rarely used any more they are virtually nonexistent within the modern commercial brewing industry.

Most clarification processes used today do not involve added finings at all but instead rely upon physical filtration methods. The beer flows through either a very fine-grade industrial microporous screen or, more commonly, diatomaceous earth. Diatomaceous earth is a chalk-like mineral product formed from the fossilized remains of diatoms, or phytoplankton with a calcareous skeleton. It is cheap, easy to replace and recycle, and is the preferred method of filtration for many craft brewers today.

Of course, nothing beats first-hand information. Virtually all American craft beer on the market today is wholly compliant with the vegan philosophy, but if you are still concerned talk to the brewer directly. Most would be happy to explain their process to you and rather flattered that you showed such a detailed interest in their profession.

What Makes Beer: Part 1 of 5

Beer is made of some rather common, everyday ingredients, and out of these few items literally thousands of styles and flavor profiles are possible. But do you really know of what your favorite beer is made? Could you explain and describe—on a fundamental level—each of the simple elements in the brewing process? Let’s try to do just that.

Brewing begins with malt, the primary taste component and flavor backbone of every beer ever made. But what is malt, besides an additive for milkshakes or a creamy breakfast cereal? Essentially, malt is cereal grain that has been malted, a process that renders the grain suitable for fermentation and a few other applications.

Remember that all cereal grains are grasses, the same type of plant that grows in your yard. The “grain” that is harvested from the whole plant is a seed kernel, whether that comes from wheat or oats or corn. Like all seeds, these small bits contain the genetic material of the plant and are used for reproduction. Put it in the soil, add a little water and sunshine, and you have a whole new plant.

Seeds are a complex little package in and of themselves. By nature’s requirement, they must be self-sustaining, meaning they should be able to sprout and grow wherever they land. To this end, included along with the genetic material of the plant is a fair amount of starch to be used as “starter” fuel once the seed germinates. This starch is intended to last long enough until sprouting leaves and roots can provide food of its own.

Malting is the process by which humans are able to take advantage of the seed’s starch reserve. It involves steeping the grains in water at a temperature just hot enough to activate (germinate) the enzymes in the seed without cooking it. Once these enzymes are activated, they set about their designed task of converting the starch present to sugars for use by the nascent plant. Ultimately, it is these grain sugars that brewers are after, and detailed recipes and parameters have been worked out for proper starch conversion.

These seedlings are well on their way to becoming plants, and would eventually bud leaves and consume all the available sugars if allowed to continue. However, at this point the grain is dried in ovens to stop the germination process and preserve what sugars are present. It is these sugars that will eventually provide nutrients for the yeast to consume later in the brewing process.

A specialty type of malt exists named crystal malt that consists of sugars converted to starches without the benefit of enzymes. Crystal malt relies solely on the heat of the ovens to caramelize the starches, and as such the resulting sugars are left unusable by yeasts. The addition of crystal malts in a recipe lends a sugary sweetness to the final beer, as the caramelized sugars persist through the fermentation process.

The brewer is left with usable malt at this stage but there may still be several options available, depending on the desired qualities of the final beer. Malt may continue to be roasted in ovens far past its dry stage to caramelize the sugars, adding a depth of flavor and color by heat and oxidation. Desired color, taste and aroma components can be developed by further roasting, in a similar fashion to that of processing coffee beans.

What is available to the brewer today is a wide array of malts from dozens of different base grains, each with its own character and fermentable sugar content and each with an additional flavor and color process. In particular, barley has been the favorite of brewers for thousands of years because of its superior enzymatic power of producing usable sugars, and almost all beers contain some amount of barley.

However, wheat, rye and oats also remain popular grains used for brewing. In theory, anything from maize to millet, sorghum to rice can be used for brewing, with each bringing its own elements of flavor and body to the palate. A skilled brewer with a notebook of proven recipes can produce a wide range of final beer styles by no more than combining the qualities and quantities of various malts.

Beer Myths, Part 1

"Ales and lagers are the same thing."

Other than both are beer, nothing is further from the truth. What distinguishes an ale from a lager is the yeast strain used and the particular method used to ferment the beer, which again depends upon the particular yeast. This yeast is the only ingredient differentiating the two, but it is important enough to make all the difference.

Ale is brewed with a yeast family known as Saccharomyces cerevisiae, a "top-fermenting" or "warm-fermenting" species, whereas lagers use species of the Saccharomyces carlsbergensis family, which prefer cooler temperatures and tend to cluster at the bottom of the tank. Although hundreds of variations exist on each, ales tend to be fuller in body and heartier, whereas lagers have a cleaner, lighter body and finish.

"Beer from a can tastes like a can."

Beer tastes like beer; cans taste like cans. One of the most prevalent problems with canned beer is drinking it directly from the opened can. With your lips and tongue in direct contact with the lid of the container, of course you are going to taste aluminum and steel. Pour it into a glass.

In the industrial past, canned beer did have a problem with the can material contributing to the flavor of the beverage it contained. However, modern beer cans are coated with a thin layer of food-grade plastic so that beer never comes into contact with metal at any point. Any contributing flavors detected are flaws in the beer itself, or else purely psychological.

"Bock is made from the leftover dregs of other beer."

The origins of this myth are puzzling but they may be attributed to the seasons of the year in which the style of bock beer itself was consumed. Bock was typically brewed in the spring for fall consumption, with a long and quiet lagering time unlike the relatively quick-fermenting ales produced year-round.

The darker color and stronger flavors of bock may have led some to believe it was manufactured from the remnants of other ales brewed in the meantime. But bock is brewed no differently than any other beer, with an initial ingredient list of malts and hops and a specialized lager strain of yeast.

"Dark beer is stronger and heavier than lighter beer."

This myth is most likely traceable to the many decades-long Guinness marketing campaigns that claim "Guinness gives you strength" or it is "A meal in a glass." While it may be true that Guinness is more full-bodied than most commercially popular light lagers today, it is by far neither stronger nor heavier.

The color of a beer is wholly a function of the initial roast of the grains used in the mash. As in coffee, darker roasts produce a darker color in the final product, and the use of adjuncts such as rice can significant lighten the final color. But neither of these has any connection to body or final alcoholic strength.

"Craft brewing is just a fad."

Modern American craft brewing has been around since the 1970s, and is presently enjoying a healthy growth curve. More to the point, what we today consider "craft brewing" or boutique products are simply what has been standard practice for centuries of local and artesianal brewing operations.

The Brewers Association tracks such growth annually, and the craft beer industry is relishing a healthier growth than their large corporate counterparts. Our sincere hope is that someday the specialty market of "craft beer" will indeed disappear, and that such quality brewing will simply be referred to as the norm.

Infection!

On the whole, most of us are healthy individuals. However, we all must deal with infectious diseases or conditions from time to time. Bacterial or viral, our bodies cannot always successfully defend against the microbes that bathe our world. We all get infections. Our pets get infections. Even our computers get infections. And believe it or not, so does our beer.

Readers should already be familiar with the role of yeast in fermentation. Whether you talk about beer, wine, vinegar, bread, yogurt, cheese, buttermilk, sauerkraut or soy sauce, the process is essentially the same: microorganisms of various cultivated yeast species eat sugars and produce alcohol, carbon dioxide and a few other chemical flavoring components. We use and breed yeast to do this because the end product tastes so good.

But what is good for domesticated Saccharomyces cerevisiae is also good for hundreds if not thousands of other microbial life-forms, ranging from mold spores, bacteria or wild yeast species native to our environment. The process is similar to that of yeast, as existing sugars are consumed, but the output of these foreign bugs can contribute flavors that range from mildly sour to absolutely vile. A rare few like Salmonella can even kill you.

The dichotomy of brewing is to develop an environment that is literally an ideal world for these microorganisms to thrive and then deliberately infect it with the germ of your choice—yeast. After boiling the hops and grains during the brewing process, the resulting cooled liquor (called wort) is a sterile landscape just waiting to be populated. And it will be quickly invaded and inhabited, either by the choice of the brewer or by the chance of whatever agent can get to it first. This is why sanitation in the brewing process is paramount.

The good news in this microscopic war zone is that yeast has been bred to be very good at what it does. Whereas professional brewers have sealed industrial equipment, homebrewers can reliably and repeatedly make good beer in their kitchen or backyard. Even if a few undesirables get into the wort, yeast can usually out-compete anything else. In this environment, yeast is generally the dominant life-form.

However, yeast isn’t bulletproof. Some infections can gain a foothold and add their own flavors to the recipe. It can happen when the yeast is pitched, or when it is transferred for bottling, or even live in the plastic lines behind a commercial tap. Some states and municipalities have their own laws and procedures for maintaining brewing and beer-serving equipment, above and beyond commercial food safety regulations.

Whatever its origin, an infected beer is not too difficult to identify. In a bottle, an infection sometimes overcarbonates the beer, leading it to gush uncontrollably when opened. Flavors that infections can impart include a sour or acidic taste like vinegar (often a result of Brettanomyces, Lactobacillus or Pediococcus), a plastic taste (often referred to as "Band-Aid"), a sulfur taste like rotting eggs or matches, or vegetal components like celery, onion or asparagus. Flavors of infection tend to resemble organic substances, as opposed to other contaminants like soap or cleansers that may add more of a chemical flavor element.

The good news is that other than ruining the taste, nothing that can grow in a beer is really harmful to humans. The pH of beer and the presence of alcohol keep almost all the truly nasty microorganisms at bay. Even drinking an infected beer won’t make you sick, although the flavor and acidity may turn your stomach. If you suspect a beer is infected, always inform the manager, the retailer or even the brewer directly. Most will be happy and eager to replace it.