Apocalypse Beer: How to Ferment Anything - The Brew Site The Brew Site Did that catch your attention? Good! Understanding fermentation is a key component to making beer (indeed, any alcohol) but it turns out, the formula for fermentation is really pretty simple: Water + Sugar + Yeast = Alcohol You might think that the yeast is the biggest unknown here, but in reality wild yeasts are abundant in nature and many fruits by themselves have an abundance of yeast naturally present on them that will start fermentation with little to no effort. No, the real unknown is the “sugar” in this equation, and thus the idea of “how to ferment anything” really means, “how to get the sugar from anything.” Once you have the sugar(s), fermentation is the easy part. Previously we covered brewing your first batch of Apocalypse Beer and it was the most basic example of the process using three basic ingredients: water, refined white sugar, and yeast. If you have easy access to plain sugar then you have a ready supply of “fermentables” to use as a base in your beer recipes. But if you don’t have that access? Read on.

There are basically two classes of fermentables that need consideration: sugars that can be fermented directly without any processing, which includes processed sugars, syrups, honey, fruits, and so on; and sugars that are locked up in starches or complex carbohydrates which require some form of processing to extract or convert the simple(r) sugars needed by the yeast. This second class includes things like grains, roots, vegetables, and anything else that doesn’t have readily-accessible sugars. Fortunately we have thousands of years of brewing development to guide us in converting these sources into fermentable sugars—for grain-based beverages (primarily malted barley). And, where malted barley (or wheat) isn’t available there are other strategies to be had for extracting what we need. Let’s overview these various sources, with more detailed explanations (if needed) of how to convert or extract their sugars to follow in future posts. (Note: I am not covering the fermentation of meat or other similar proteins.

This is an entirely different beast, so to speak, and as far as I know there’s no history or tradition of brewing fermented meat beverages.) “Simple” Sugars (No conversion required) These are fermentables that are already in ready-to-ferment sugar form that the yeast will be able to convert into alcohol easily. Many of these you may be able to find from a scavengeable source; others occur naturally. Very easy to ferment: just add water and yeast. White sugar: This is refined, so you won’t find it in nature, but you may well come across it during your excursions. Cane and corn sugar are 100% fermentable, while confectioners’ (powdered) sugar has filler and is about 97% fermentable. Look also for sugar cubes and sugar sweetener packets. Brown sugar: Also refined, your typical grocery store brown sugar (what you’ll most likely find) is simply white sugar with a bit of molasses added for color. “Raw” sugar: The kind of less-processed sugars commonly found in upscale and health food stores, with examples such as demerara sugar, Turbinado sugar, and Barbados sugar.

Honey: You may find processed honey or you may be lucky enough to find wild beehives to supply you with natural honey. Honey is 90-95% fermentable and will thus handily replace other sugars if needed. Molasses: A by-product of the sugar refining process that appears as dark brown to black and color and comes in several grades; it is about 75% fermentable but this can vary. Syrup: Any of a variety of processed syrups you might find, including maple, corn syrup, rice syrup, agave, and birch. The fermentability of different syrups will vary, and it’s also important to remember that many commercial offerings were “fortified” with plain corn syrup (if that matters to you). Tree Sap Of course if you are familiar with maple syrup then you probably realize that this comes from concentrating the sap of the maple tree, which is obtained by drilling a small hole in the trunk of the tree and collecting the clear sap that runs out of it.

Maple trees are the most common tree to collect sap from, and they typically have a sap sugar content of around 2% on average—which means there is a need to concentrate the raw sap down to syrup form, which can often be at least a 40-to-1 ratio. In other words, you need to boil 40 gallons of sap down to get 1 gallon of syrup. If there are few or no maple trees where you are, there are fortunately other trees besides maple which yield usable sap: birch, sycamore, walnut, larch, and lime. That list plus several techniques for tapping a tree to get at its sap can be found here , one of which may work well for post-apocalyptic sugar hunters: cutting or breaking off the ends of small branches and collecting the sap in plastic bottles. Fruits It almost goes without saying that fruits are full of fermentable sugars that you easily use: chop or mash them up and use them directly in your wort, no further processing is necessary (besides peeling and pitting, etc.).

Of course different fruits have different (average) concentrations of sugar; here’s a sampling: Apple: 11.8% Pineapple: 12% Strawberry: 5.1% More here . Bear in mind, the fruits don’t have to be fresh: if you can scavenge canned fruit, that will work just fine (as will the syrup the fruit is canned in!). Juniper Berries While technically a fruit, juniper berries rate a special mention because besides being used for flavoring gin, I suspect most people would be surprised to find out that juniper berries in fact have a high percentage of dextrose sugar—up to 30%! Stephen Harrod Buhner in Sacred and Herbal Healing Beers writes: The presence of such a large amount of dextrose may account, in part, for the use of juniper and juniper berries as an integral part of Norwegian brewing… juniper beer was sometimes made with juniper, water, and yeast only—no other source of sugar being used.

Beets Beets are a root vegetable but they get special mention here (as well as in the next section) because they are naturally so full of fermentable sugars already that you can cook them down to extract the juice and use that directly in your brewing as you would any other fruit juice or syrup. Beets are in fact so sugar-rich that a large percentage of refined white sugar comes from them! Packaged Foods In the course of your scavenging and salvaging, former grocery stores and other markets may provide some valuable source of brewing fermentables—provided they haven’t been completely looted. Many packaged foods are full of sugar you can brew with (provided you aren’t eating them instead!), such as: Breakfast cereals Jams and jellies Fermentables that require “unlocking” (converting from starches) Sugars that are locked up in starches, such as those found in most grains and vegetables, require enzymatic conversion to transform those starches into sugars.

(The science behind this is because large starch molecules are really lots of smaller sugar molecules all strung together, and particular types of enzymes called amylases can break these down into those individual sugars.) You might be wondering where you might find the amylase enzymes needed to transform these materials into fermentable sugars—after all, this sounds very industrial and scientific and since society has collapsed, surely this isn’t possible, right? Wrong! Two of the main grains used in the production of beer develop the enzymes naturally. You just need to know how to make use of them. (Actually amylase enzyme is available commercially but I have no idea how easy it will be to find in a post-apocalyptic setting. Of course you could raid your local homebrew supply store before the looters get there any take any and all enzyme you can find…) Grains: Barley and Wheat These are the two (traditional) staple grains used in brewing and the primary source of fermentables in beer. Of course the grains themselves aren’t simply thrown into a kettle of water and cooked: you’ll get hot cereal. Instead there is a two-stage process required to extract the enzymes and then the sugars from them.

Malting: The raw grains are first germinated, or sprouted, by soaking in water and then keeping moist; this causes the grain to start producing the necessary enzymes that will be needed in the later steps. Once the grains have sprouted just enough (typically the sprouted part, or “acrospire,” is as long as the grain itself, if not a little shorter), the process is stopped by drying or kilning the grain. There is a good (if a bit technical) article on malting here that will get you started. The resulting malted grains should have the proper levels of enzymes that will convert their starches to sugars during the next stage (mashing). Mashing: The malted grain is crushed and soaked in hot water (150°F is a good target) for at least one hour, then the resulting liquid is rinsed into the brew kettle and boiled. What’s happening is the hot water has activated the enzymes formed during malting, and they are converting the grain starches into sugars—giving us the fermentables we need to make beer.

It gets better: barley and wheat have a special place in brewing because they already naturally have enough enzymes to perform the starch-to-sugar conversion, while other grains may not; and in fact, these malts are usually also able to convert the starches from other types of grains—and other starchy sources, too—up to a point. This will prove incredibly useful when you are working with the following materials which may otherwise be inaccessible to you for brewing. Grains: Other Any variety of grain can be combined with malted barley and/or malted wheat in the mash (hot water bath) to take advantage of the enzymes present in the malt to convert the various starches to sugars: rye, oats, rice, corn, sorghum, millet, quinoa, amaranth, and so on. Many of these grains need to be cooked in boiling water prior to being added to the mash to gelatinize them, which makes them open up their starches to the conversion process.

There are also several grains that, like barley and wheat, can be malted to develop the amylase enzymes that will allow them to convert their starches to sugars without help: oats, rye, and sorghum all have high enough diastatic power to do this. (“Diastatic power” is the measure of how much starch-converting enzymes a grain may contain. The higher the diastatic power, the more it can break starches down to sugars.) Rice (and an alternative to malting and mashing) Rice deserves a special mention in this section because of both its long use in Asian fermented beverages like chang and sake , and the fact that it cannot be malted—which means that rice doesn’t contain the amylase enzymes that malting develops to ultimately ferment it. When used with malted barley or wheat it needs to be cooked and mashed like other grains; but in sake brewing, there are no other grains, malted or otherwise. So the question arises: just how are the starches in rice (by itself) converted to fermentable sugars? The answer is “mold” and it provides a second, interesting avenue to explore for processing grains.

The rice in sake and chang brewing is fermented by the addition of special yeast cakes containing fungi, primarily Aspergillus oryzae, which do the work to convert all the available starches to sugars which the yeast in the cake subsequently ferment. In the making of sake the addition of special Aspergillus-infected rice, called koji, does this work. And there’s no reason this special mold couldn’t be added to any other cooked grain to work its conversion magic. Now obviously you can’t just pop into your local Asian market in the post-apocalyptic world and pick up a yeast cake or koji to prepare your grains and brew your beer; so what to do? Fortunately there is a natural source of Aspergillus fungi which you can use here: ginger root. Here’s Buhner again: The simple addition of crushed gingerroot to any cooked starchy grain will result in starch conversion and the subsequent growth of Saccharomyces yeast and the beginning of fermentation. This will be a slower process—days rather than hours for mashing (though this evens out more if you count time for malting)—but it should be no less viable.

Sweet Potatoes Sweet potatoes rate a special mention as not only do they already have a naturally high sugar content, but they also have enough natural amylase enzymes and diastatic power to convert their own starches without using barley (or wheat), making an all-sweet potato beer a possibility. For this to work it may required raw sweet potatoes—canned sweet potatoes have likely undergone the high-heat cooking/pasteurization/sterilization of the canning process which would denature (destroy) the amylase enzymes needed for self-conversion.

(You could still add canned sweet potato to a grain mash to convert the gelatinized starches to sugars though.) Two good sources (with additional links) to read up on this process are here and here , but the basic process should be: Grate, slice, chop, or otherwise mash up the raw sweet potato into small bits; Add water to mash at a temperature of about 140 degrees Fahrenheit (1 gallons of water to 2-3 pounds of potatoes might be a good ratio); Mash for 60 to 90 minutes, then remove the potato from the water and add it to a separate pot of boiling water (1 gallon), and boil for 30 minutes and thoroughly mash the potatoes; Add it all back to the mash water to raise the temperature to 150-155 degrees Fahrenheit, and let this rest for another hour. The resulting should be about 2 gallons of wort full of sweet potato sugars, and fermentable. Beets Beets were mentioned in the “simple sugar” section above for a very good reason—they are already full of fermentable sugars! You can cook beets down to extract the juice and use that juice directly in the beer brewing, no conversion process required.

(You could still mash them with your malted grains, if you like.) Vegetables Other types of vegetables fall (roughly) into three categories: 1) starchy (often root) vegetables like potatoes, turnips, and parsnips which need to be cooked and mashed along with malt in order to extract their sugars; 2) vegetables that contain sugars (but little to no starch) that can be used directly in the beer without additional processing; and 3) vegetables that contain little of either starches or sugars but may be high in fiber like lettuce, celery, and mushrooms (though those are technically fungi). Some examples of each of these categories are: Potatoes, broccoli, cauliflower, turnips, parsnips, beans, peas, corn (as a grain of course), sweet potato (also see above), squash, pumpkin — processing the starches is required, whether mashing with malted grains or using Aspergillus fungi. These should all be fully cooked before using. Carrots, bell peppers, sweet potato (also see above), onions, beets (also see above) — these can be added directly to the beer while brewing, cooked or raw, and should be chopped or mashed finely to maximize the sugar extraction.

Lettuce, celery, radishes, mushrooms, green onions, cucumber, many greens — these would be better suited as flavor components. It’s important to note that unless you have a supply of fresh vegetables (perhaps you’re growing your own, or finding wild veggies—or even raiding others’ gardens?) you may be relying on what canned vegetables you are able to salvage from abandoned markets and stores. Orchid Roots Did you know orchids are edible ? Indeed they are, and in particular the roots are nutrient-rich starchy tubers—very much like potatoes or parsnips. As such, you should be able to process these in the same type of way: boil them until they are soft (to gelatinize the starches), chop finely or (better) mash them up, and add them to your mash with barley or wheat to covert the available starches to sugars. Orchid beer, anyone? Packaged Foods As in the previous section, you may run across old groceries and markets that may be scavengeable for brewing fermentables.

In the previous section we covered packaged foods containing sugar; here are some examples of foods you’ll have to process in one of the ways described above to get the sugars out of them: Granola, granola bars Pasta and noodles — for the most part this is flour and water, i.e. all starch Breakfast cereals — the kind that focus more on grains and fiber rather than sugar Baked beans — not only are the beans already cooked (easier to convert) but the sauce they’re canned with is full of sugars Nuts Nuts actually don’t provide much in the way of fermentables, as they are largely made up of protein and fat in the form of oils. So while you can’t ferment nuts directly, you can still add them to your beer where they will add a flavor contribution. Be aware though that with too many nuts, the oils can affect flavor and head retention (if that’s something you’re looking for). Have I missed anything? This article covers a lot of ground and should help give you the tools you need to figure out how to ferment many foodstuffs you’ll likely come across.

But if I’ve missed anything or there are further ideas, leave a comment below or contact me directly , and I can round up the suggestions in a future post. And I’ll post additional eclectic sources and ideas for brewing fermentables as I come across them as well— Buhner’s book alone is chock full of good ideas! Fermentation | Wyeast Laboratories Production of flavor compounds such as esters, diacetyl, sulfur containing compounds, etc. Consumption of most wort sugars The temperature of the primary fermentation should be regulated according to the desired flavor and aroma profile. The following is a guideline: Primary Fermentation Temperatures: Ales: 62°F – 75°F (17°C – 24°C) Lagers: 46°F – 58°F (8°C – 14°C) *Note: Lager fermentations can be started warmer (~60°F, 15.5°C) until signs of fermentation (gravity drop, CO2 production, head formation) are evident. Cool to desired fermentation temperature once signs of fermentation are observed.

Wheat and Belgian styles: 62°F – 85°F (17°C – 29°C) Secondary Fermentation The secondary stage of fermentation refers to the stage of fermentation after the majority of the wort sugars have been consumed and there is a sharp decrease in the rate of fermentation. During this period, most of the final sugars are depleted and some secondary metabolites are converted by the yeast. Yeast flocculation and settling begins to occur due to the increase in alcohol content and the depletion of sugar and nutrients. Diacetyl reduction takes place during secondary fermentation and during the diacetyl rest that some brewers incorporate into the secondary stage of fermentation. Secondary Fermentation Summary: Decreased rate of ethanol and CO2 production Diacetyl Conversion Reduction of some flavor compounds by yeast metabolism or CO2 scrubbing Terminal gravity is reached Yeast flocculation and settling begins Secondary Fermentation Temperatures: Ales: Same as primary fermentation (higher temperatures will increase diacetyl reduction rates) Lagers: 40°F - 60°F (4°C - 15°C). Some brewers allow the beer to increase in temperature to speed the diacetyl reduction.

This increased temperature is usually only sustained for 24 to 48 hours. Wheat and Belgian Beers: Same as primary fermentation (higher temperatures will increase diacetyl reduction rates). Conditioning The conditioning stage takes place when the terminal gravity has been reached and the tank is cooled to refrigeration temperatures (31°F - 38°F, 0°C - 3°C). During this time the yeast continues to flocculate and settle. The yeast also conditions the beer by reducing various undesirable flavor compounds. Ales do not benefit from long conditioning times like lagers do. The desirable flavors in ales will decrease with age and therefore it is recommended that conditioning be as short as possible before packaging. Exposure to oxygen at this stage is extremely detrimental to beer quality. Conditioning Summary: How Breweries Kept Busy During Prohibition | Mental Floss How Breweries Kept Busy During Prohibition Wikimedia Commons Like us on Facebook Before Prohibition , there were over 1300 breweries in the United States , and the popularity of ales and lagers was at an all-time high.

The party ended in 1920, however, when beer was deemed an "intoxicating liquor" by the Volstead Act—the legislation passed to enforce national prohibition and the 18th Amendment—and it became illegal to make, transport, or sell suds. Unlike underground distilleries that could whip up batches of illegal liquor with little threat of detection, breweries were often big, tax-paying businesses that couldn't just slip into the woods with their massive boil kettles and lauter tuns. How did the few breweries that survived the 13 years of Prohibition do it? The 18th Amendment didn't pop up overnight, and some brewers had time to prepare. Prohibition was a topic of national debate since before there was even a nation, and its enforcement was centuries in the making.

In 1885, a group of German-American brewers called the Wisconsin State Anti-Prohibition Association published a pamphlet arguing against new taxes and a proposed ban on one of the state's most lucrative products: Many thousands of people are doing business with the brewers, many thousands of laboring men, mechanics, and artisans...And the prohibition fanatic who wants to destroy the business at once by legislation will please step forward and tell us what he would give to [Milwaukee] in return for the destruction of its most extensive and important business interest. Beer in America was popularized by German immigrants, and German-Americans owned and operated most of the breweries. During WWI, anti-German sentiment ran rife so arguments like the one above went ignored (or were used as an example of beer's inherent evil). The country was sliding towards a full alcohol ban and was already primed by temporary wartime prohibition, which was enacted in order to preserve the nation's grain supply. Breweries could only make "near beer," or beer that didn't exceed an alcohol content of 2.75%. Once the Volstead Act was put in place, that number had to drop to 0.5%.

Many breweries stuck to near beer, but others that had the means were able to get creative: Ice Cream Facebook Both Anheuser-Busch and Yuengling refocused their manufacturing attentions on a more legal vice: ice cream. Anheuser-Busch owned a fleet of refrigerated trucks and used them to transport their new brand of dessert. Yuengling became the Yuengling Dairy Products Corporation and kept making ice cream until 1985. They reopened their dairy division this year and you can buy the stuff from their website . Pottery Coorstek ceramics via Wikimedia Commons Adolph Coors' glass works (which had originally produced bottles for Coors beer) was converted to a porcelain and pottery company long before Prohibition was an immediate threat. During the alcohol ban, Coors expanded its pottery d ivision and mass-produced ceramic tubes and rods for the military and dinnerware lines. Malt Extract Wikimedia Commons Many breweries, including the manufacturers of Schlitz, Miller, and Pabst, turned their attentions to malt extract . They advertised it as a cooking product and put the following instructions on the packaging: "For bread making use one half as many tablespoonsful of malt extract as formerly used of sugar.

This will make the bread light and perfectly browned.” The real reason people bought it, however, was to use it in making their own beer, or "home brew." Brewing beer at home was illegal under the Volstead Act (unlike wine, which one was allowed to make), and many malt extract producers ended up being raided by Prohibition agents. A court eventually ruled that the extract was legal, and people were able to make as much, um, bread as they wanted. Dyes Wikimedia Commons WWI stalled the importing of dyes to the U.S., and this "dye famine" lasted long after the war's conclusion. This coincided with Prohibition and, rather serendipitously, many brewers noticed their existing equipment could easily be converted into making dyes . F. M. Schaefer Brewing Company, Nuyens Liquers, and the Lion Brewery (renamed The Noil Company) all restructured their operations to make dyes. Brewery owners weren't the only people who noticed the similarity between alcohol and dye production; in a tasty reversal, many dye chemical plants converted to make illegal hooch.

How To Brew Beer Step 3: Fermenting - Homebrewing 101 - Northern Brewer To provide an environment in which the yeast can accomplish a healthy and clean fermentation. You’ll Need: Your primary fermenter, blow-off assembly, siphon, sanitizer and secondary fermenter (optional). *Note: Checking Your Gravity While your specific gravity will begin to drop during the fermentation period, this is an aspect you should trust and not necessarily test. You want your beer to be exposed to as little possible contamination as possible. Every time you unseal the airlock, this exposure occurs. A good rule of thumb, measure your original gravity prior to pitching your yeast, then at any time you might transfer your beer, either to another container or, finally, during bottling/kegging. Directions: Primary Fermentation Within a day or two of brew day, fermentation begins. As the yeast convert malt sugars into CO2 and alcohol you will see bubbles come through the airlock. The specific gravity will steadily drop and a cap of thick tannish foam called krauesen forms above the beer. You may want to store your brew in an area that is easily cleaned, a particularly violent fermentation could cause a bit of a mess.

Violent? Yes, violent. As with anything that builds with increasing gas levels, explosions can occur. Explosions are most common if your airlock fills with gunk essentially stopping the flow of gas out of the carboy. If your krauesen starts filling your airlock. You may want to initiate a blowoff set up. Roughly one to two weeks from brew day, fermentation ends. Bubbles coming through the airlock become very slow or stop entirely, the specific gravity is stable and the cap of foam starts to subside. Secondary Fermentation During our fermentation process, we see a layer of krausen form atop our beer, where does it go? That krausen normally dissipates over time and any remaining grain particles, hop particles and dead yeast cells will accumulate instead at the bottom of your fermenter in a mass known as “trub”. While sitting on this trub for a short while can impart flavors we want to see in a beer, letting our brew sit atop this trub for too long can create flavors we don’t want.

To avoid these flavors setting in, we will “rack” (siphon) the brew out of the first fermenter, careful to leave the trub behind and into a new, clear and clean fermenter. Doing so allows the brew to settle out and condition in flavor. It also give the brewer an opportunity to clear out the beer, after racking the beer into a secondary fermenter, still more trub may form, but when racked into bottles during the final stage the beer should be less hazy and more clear than it started off. Remember, when racking into a new, secondary fermenter, it is equally important that this vessel is clean and sanitary. Be sure to sanitize your auto-siphon, your carboy, your airlock and stopper and any tubing that may come in contact with the brew. Alcoholic fermentation, of sugar into CO2 and alcohol Alcoholic fermentation by yeast cells [Lactic acid fermentation by lactic bacteria] In brewing, alcoholic fermentation is the conversion of sugar into carbon dioxide gas (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes. This is in fact a complex series of conversions that brings about the conversion of sugar to CO2 and alcohol.

Yeast is a member of the fungi family which I like to think of as plants but strictly they are neither plant nor animal. To be specific yeast is a eukaryotic micro-organism. Not all yeasts are suitable for brewing. In brewing we use the sugar fungi form of yeast. These yeast cells gain energy from the conversion of the sugar into carbon dioxide and alcohol. The carbon dioxide by-product bubbles through the liquid and dissipates into the air. In confined spaces the carbon dioxide dissolve in the liquid making it fizzy. The pressure build up caused by C02 production in a confined space can be immense. Certainly enough to cause the explosion of a sealed glass bottle. Alcohol is the other by-product of fermentation. Alcohol remains in the liquid which is great for making an alcoholic beverage but not for the yeast cells, as the yeast dies when the alcohol exceeds its tolerance level. Overall chemistry of fermentation The overall process of fermentation is to convert glucose sugar (C6H12O6) to alcohol (CH3CH2OH) and carbon dioxide gas (CO2).

The reactions within the yeast cell which make this happen are very complex but the overall process is as follows: C6H12O6 ====> 2(CH3CH2OH) + 2(CO2) + Energy (which is stored in ATP) Sugar ====> Alcohol + Carbon dioxide gas + Energy (Glucose) (Ethyl alcohol) From the above it seems nice an simple chemistry one mole of glucose is converted into two moles of ethanol and two moles of carbon dioxide but in reality it is far from this clear. There are many by products. In addition to CO2 and alcohol, the sugar is incorporated into other by products such as yeast biomass, acids (pyruvic, acetaldehyde, ketoglutaric, lactic), glycerol. Hence if you read many home brewing books there is a table estimating the conversion of sugar into alcohol. These tables tend to be derived from measurements rather than a set formula. The efficiency of the yeast and fermentation conditions alters the proportions of various by-products meaning a simple single formula is not available. Wine makers will see different efficiencies to beer makers. Fermentation conditions such as temperature vary the production of by products.

This knowledge is used by wine makers to get fuller bodied wines by brewing in conditions that causes fermentation to produce more of the by-product glycerol. Fermentation by-product Glycerol gives wine its body. From time to time you read in the press a very shocking tale of people adding anti-freeze to wine but this statement on its own does not tell you the full extent of the danger. Bear in mind Glycerol can be used as an anti-freeze and is a natural by product of fermentation but not all anti-freeze use glycerol, most use very toxic alternatives. So the statement "Anti-freeze added to wine" does not tell you if highly toxic chemicals were added or just Glycerol to supplementing the natural Glycerol content. In fact Glycerol is used in health foods and is essential in fine wines. Wine produced in conditions where there was low production of the glycerol by-product can tempt the producer to add something to boost the wine's body. Adding food grade Glycerol to boost a wine's body is not ideal but no need for panic as glycerol is natural and is often used in food products. Adding toxic anti-freeze to boost a wine's body can and does kill people.

Note: The sugars used can be a range of fermentable sugars. These sugars are converted by enzymes to glucose which is then converted to alcohol and CO2. Some sugars are not able to be fermented and will remain in the liquid. Fermentation and yeast in brewing Brewer's yeast tolerate up to about 5% alcohol. Beyond this alcohol level the yeast cannot continue fermentation. Wine yeast on the other hand tolerates up to about 12% alcohol. The level of alcohol tolerance by yeast varies from 5% to about 21% depending on yeast strain and environmental conditions. The fermentation process has limits such as temperature. Greater than 27C kills the yeast less and than 15C results in yeast activity which is too slow. Not all sugars are fermentable. Non fermentable sugars in solution will remain after fermentation and will result in a sweeter end product. Malt has non fermentable sugars which can be used to balance the bitterness of the hops. The amount of sugar in the solution can be too much and this can prevent fermentation. Some wine recipes suggest adding the sugar in parts throughout fermentation rather that all at the beginning. This is especially true if the brew is aimed at producing a high level of alcohol.

Some yeast strains have evolved to handle higher sugar levels. Yeast such as Tokay and Sauterne handle high levels of sugar. The normal, home brewing, fermentation is in two parts. Part 1 Aerobic (Oxygen is present) This is the initial rapid process where the yeast is doubling its colony size every four hours. (Usually 24-48 hours) Fermentation - How Beer Works | HowStuffWorks How Beer Works Photo courtesy Carolina Brewing Company Fermentation is the process by which yeast converts the glucose in the wort to ethyl alcohol and carbon dioxide gas -- giving the beer both its alcohol content and its carbonation. To begin the fermentation process, the cooled wort is transferred into a fermentation vessel to which the yeast has already been added. If the beer being made is an ale, the wort will be maintained at a constant temperature of 68 F (20 C) for about two weeks. If the beer is a lager, the temperature will be maintained at 48 F (9 C) for about six weeks. Since fermentation produces a substantial amount of heat, the tanks must be cooled constantly to maintain the proper temperature.

These fermentation tanks hold more than 2,400 gallons (9,085 L), which means that it takes four batches of wort to fill one tank. Since fermentation takes at least two weeks, the capacity of the brewery is limited by how many tanks they have. Up Next Test Your Knowledge: Experimental Foods When the wort is first added to the yeast, the specific gravity of the mixture is measured. Later, the specific gravity may be measured again to determine how much alcohol is in the beer, and to know when to stop the fermentation. The fermenter is sealed off from the air except for a long narrow vent pipe, which allows carbon dioxide to escape from the fermenter. Since there is a constant flow of CO2 through the pipe, outside air is prevented from entering the fermenter, which reduces the threat of contamination by stray yeasts. When fermentation is nearly complete, most of the yeast will settle to the bottom of the fermenter. The bottom of the fermenter is cone shaped, which makes it easy to capture and remove the yeast, which is saved and used in the next batch of beer. The yeast can be reused a number of times before it needs to be replaced.

It is replaced when it has mutated and produces a different taste -- remember, commercial brewing is all about consistency. While fermentation is still happening, and when the specific gravity has reached a predetermined level, the carbon dioxide vent tube is capped. Now the vessel is sealed; so as fermentation continues, pressure builds as CO2 continues to be produced. This is how the beer gets most of its carbonation, and the rest will be added manually later in the process. From this point on, the beer will remain under pressure (except for a short time during bottling). When fermentation has finished, the beer is cooled to about 32 F (0 C). This helps the remaining yeast settle to the bottom of the fermenter, along with other undesirable proteins that come out of solution at this lower temperature. Now that most of the solids have settled to the bottom, the beer is slowly pumped from the fermenter and filtered to remove any remaining solids. From the filter, the beer goes into another tank, called a bright beer tank. This is its last stop before bottling or kegging . Here, the level of carbon dioxide is adjusted by bubbling a little extra CO2 into the beer through a porous stone.

How Yeast Makes Alcohol and Carbon Dioxide When the yeast first hits the wort, concentrations of glucose (C6H12O6) are very high, so through diffusion, glucose enters the yeast (in fact, it keeps entering the yeast as long as there is glucose in the solution). As each glucose molecule enters the yeast, it is broken down in a 10-step process called glycolysis. The product of glycolysis is two three-carbon sugars, called pyruvates, and some ATP (adenosine triphosphate), which supplies energy to the yeast and allows it to multiply. The two pyruvates are then converted by the yeast into carbon dioxide (CO2) and ethanol (CH3CH2OH, which is the alcohol in beer). The overall reaction is: Defining Beer Gravity | CraftBeer.com Defining Beer Gravity Defining Beer Gravity July 17, 2012 If there is one thing I retained from high school chemistry, it’s that you measure the meniscus of a liquid—and that base burns are far sneakier than acid burns.

Back then, no one mentioned that my future understanding of brewing science would vastly benefit from retaining a little more than the gossip of my first period chemistry class. Still, I was able to hold on to a few of the most simple of scientific procedures, like you must look at the bottom of the bendy-thingy when measuring a liquid. Since I enjoy masquerading as a brewer from time to time in my garage, this basic rule of measuring has proven valuable as it’s a very important part of the seemingly never-ending variables when brewing: gravity. What is Beer Gravity? You may have never heard the term gravity as it relates to brewing; you’re likely more accustomed to Newton’s version. That gravity’s cool too—it keeps beer in your glass and everything from spinning off into space—but perhaps you’ve noticed a gravity reading on a beer label or tap list and not known what it was. A gravity reading refers to the total amount of dissolved solids in water, since we’re talking about beer, those dissolved solids are sugars. These sugars are consumed by yeast to convert the wort (unfermented ingredients) into beer.

It’s read as a sequence of numbers that starts with the number one followed by a decimal to the thousandth place, something like this: 1.052. A gravity reading taken just prior to yeast being added, or pitched, is referred to as the original gravity (OG). The OG will provide the brewer with a good idea of the potential alcohol percentage for that particular beer. For example, the OG of an imperial stout at 1.080 (read: ten-eighty) has more sugar molecules to be converted into alcohol than an ordinary bitter at 1.032 (say it like this: ten thirty-two), this explains why the stout will pack more alcohol (~8.0-12.0% ABV) than the bitter (3.2-3.8% ABV), and why more malt is needed in the imperial stout recipe than the ordinary bitter recipe. The OG reading is very important to the execution of the brew and subsequent fermentation of the beer. Brewers will track the specific gravity (SG) for the duration of the process to make sure that the gravity levels remain consistent from one batch to the other and that no problems arise from the malt quality, brewing process or yeast productivity.

How Gravity is Measured If you’ve ever purchased a homebrew starter kit, you’ve likely received among other items, a clear plastic tube with an oversized thermometer-looking-deally (that’s the last time, swear) with incremental hash marks called a hydrometer. A hydrometer, also known as a saccharometer, is used to measure SG as it compares to water, which has a SG of 1.000. The more dense the solution, the higher the hydrometer will float, showing a reading above 1.000. For example, with a hydrometer reading of 1.052, the numbers to the right of the decimal (52) are the gravity units (GU). Read simply, the density of the wort is 5.2 percent higher than that of water. As yeast works to consume the sugar, the density of the wort is decreased, which causes the hydrometer to deliver a reading closer to 1.000. While gravity can be measured on different scales—Balling, Plato and Brix—Plato (which has nothing to do with the philosopher) is often used by brewers.

On a beer label, Plato is usually provided along with the OG, here’s an example: OG: 1.080 | 20°P. Notice that you can approximate Plato by taking 1/4 of the gravity units. Different fermentables—rye, barley, honey, fruit, maple syrup, etc.—yield different increases in gravity, due to the varying amounts of fermentable sugar found in them. For instance: two-row malted barley will not provide as large an increase in gravity as table sugar because the table sugar is fully fermentable whereas two-row is not. Knowing the amount of fermentable sugar in different ingredients allows brewers to figure out how much of each fermentable will achieve the desired OG of the beer. Gravity in the Brewhouse A brewer may take samples of wort from just about any point in the process in order to keep track of the SG. Arvada Beer Company’s Dennis O’Harrow (right) starts taking readings as soon as his malt is mixed with hot water at his Colorado brewery. He does this, “to see that the OG remains consistent batch to batch,” said O’Harrow.

“It lets us know that malt we receive is consistent [in quality].” At Willoughby Brewing Company in Willoughby, Ohio, Rick Seibt begins taking gravity readings as he starts to separate the liquid wort from grain husks in the mash tun. “Our brewery doesn’t have much automation, so we probably take more [gravity readings] than normal to ensure the highest level of consistency we can,” said Seibt. “We start taking readings once mashing is complete and vorlauf (recirculation of wort) has begun, to see the gravity of the first runnings (concentrated initial runoff from the mash). This will usually tell us if we have any conversion problems.” Both brewers periodically check the gravity throughout the boiling of the wort. O’Harrow uses a refractometer (a similar density measurement tool that employs the Brix scale), while Seibt employs a trio of saccharometers with varying scales, to ensure accuracy. During fermentation each brewer will take readings, generally every other day. “Taking gravity readings during the brew and subsequently throughout the ferment allow you to know the alcohol by volume and maintain a consistent product,” explains O’Harrow.

“Not only do you want to take readings consistently, but you also want to keep copious records of readings taken so that one can go back to previous brews to make again.” Seibt echoes the need to take notes: “We also use it to keep track of brewhouse yield, which then allows us to better predict the outcomes of new recipes.” The Importance of Gravity Provided that gravity readings check out, or steps are taken to adjust inconsistencies, brewers then look for healthy and cooperative yeast to drop the beer’s gravity to a specific range decided upon by the brewer or to match the style, this gravity is called final gravity (FG). The difference between OG and FG will reveal the apparent attenuation—the percentage of fermentables that were successfully converted to sugars. While gravity is important to a brewer, beer fans can benefit from understanding it too. As a beer enthusiast, an understanding of gravity will help you make informed decisions when choosing a beer if styles are not provided. You can infer that a stout with an OG of 1.080 likely has a stronger ABV than a stout at 1.044.

A craft beer described as ‘high gravity’ is referring to the strength in alcohol, a detail that adds to the beer’s character. As we continue to expand our ability to describe beer and understand brewing, details such as these aid in both aspects. You might even catch the bug to brew your own beer—dipping your toes into the the hobby of homebrewing. If so, visit my friends at HomebrewersAssociation.org . New homebrewers may not be able to hit target gravities on their first brew, but taking a gravity reading and seeing a change during the fermentation period is certainly a good start! At the very least, you know you were able to provide a conducive environment for yeast to convert sugar to alcohol. But for that, you’ll need to know what a meniscus is. About the Author: Banff Ave. Brewing Co. - 2nd Floor, 110 Banff Ave, Clocktower Village Mall - Banff, Alberta How Beer is Made What is Beer? Quite simply, beer is a fermented, hop flavored, malt sugar tea. There are four basic building blocks needed to make beer: water, malted barley, hops, and yeast.

Yeast, (often listed as a fourth ingredient, although not a part of the finished product) is used to ferment the hop flavored malt sugar tea into a effervescent (bubbly) liquid with an average of between three and seven percent ethyl alcohol. (In some cases, such as a Barley Wine, the alcohol content can go to almost 11%.) Both lagers and ales are made from essentially the same four building blocks with the major variation being the type of yeast used to ferment the product. What is Malted Barley? Malt is barley (a type of grain) which has undergone the malting process. This process consists of two primary steps. First, the raw barley is soaked in water which allows it to begin germination. This is the first phase the grain would endure if it was to grow into a plant. During this phase, enzymes are produced to be used later to break down the starches in the grain into sugars. Chemically, starch molecules are simply several sugar molecules joined together. It is these sugars that would provide the energy needed for the seed to grow into a plant. The second stage of the malting process halts the growth of the barley.

Varying temperatures of hot air are used to dry the grain (kilning). Depending on the temperature and length of kilning, different colors – and subsequently flavors – of malted barley are produced. Generally, the higher the temperature in the kiln, the darker the color and the stronger the flavor of the beer it is used to produce. What are Hops? Hop plants are a perennial climbing vine (a member of the hemp family) which grow in cool climates such as Northern Europe, the Pacific Northwest and New England. During the hot summer days, they can grow several inches a day. Eventually a hop vine can grow to 15 - 18 feet in height. A single plant carries either male or female flowers. Brewers use only the cone-shaped flowers that hang downward from the vines of the female hop plant. Hops provide bitterness, flavoring, and aroma to beer. Their most important role is to balance the sweetness of the malt. Hops are also used as a natural preservative - beer with hops keeps fresher longer. What is Yeast? Yeast is a living organism – a fungus. Yeast metabolizes (eats) sugars into carbon dioxide (CO2) and ethyl alcohol.

The most important thing to know about brewing yeast is that there are two primary types: Lager yeasts & Ale yeasts. Ale yeasts ferment warmer and quicker producing a fruitier and sweeter beer. Lager yeasts ferment cooler and slower producing a dryer, cleaner tasting beer. Lager yeasts have only recently become more predominant due to improved technology. Because of their slower, cooler fermentation, they are more susceptible to bacterial infections and are therefore more difficult to brew with. How is Beer Made? The brewing process goes as follows: A selection of malts are weighed out and ground in a mill. This ground malt, called grist, is then mixed in a large open tank, called a mash tun, with warm water (~70°C). The mixture, called mash, sits for approximately 90 minutes. During this “rest”, enzymes break down the starches from the malt into sugars. The sweet liquid is then separated from the ground malt (now mainly husks) and pumped into a large tank for heating – the kettle. The liquid is then boiled for another 90 minutes. Hops are added at precise times during the boil to properly bitter, flavor, and add aroma. Hops added early provide strong bitterness.

Hops added durning the middle of the boil add mostly flavor. Hops added late in the boil add aromas. The boiled liquid, now called wort, is then cooled to room temperature and pumped into a fermenter. Yeast is added and the mixture is left to sit. Over the next 14-21 days, the yeast ferments the wort. The fermentation process is complete when all of the sugars have been converted into alcohol and CO2. The “green” or “new” beer is then cooled again, this time to 0°C, to allow the yeast to settle to the bottom of the tank. The yeast is collected and used again for the next batch. The beer is then pumped into a conditioning tank for aging. Finally, after sufficient time has passed to mature the beer, and enough carbon dioxide has been added, the beer is ready for drinking! Homebrewing Basics: All About Grain | Serious Eats Homebrewing Basics: All About Grain [ Photographs: Sarah Postma ] Grain is the backbone of every beer. It's what gives beer much of its flavor and appearance, and it provides the simple sugars which will be fermented into alcohol.

Grain's protein can take credit for the head retention and cloudiness in a Hefeweizen and the silky mouthfeel of your favorite stout. Grain also produces complex sugars which leave residual sweetness and can add flavors that range from bread-like, to toffee, to chocolate or coffee. Malting Before grain can be converted into alcohol, the complex carbohydrates need to be broken down into simple sugars. In modern brewing this is a two step process. The first step happens before the brewer gets their hands on the grain. Barley is soaked in water, and then slowly dried in a kiln. This allows the grain to sprout, which begins breaking down the complex carbohydrates and also produces proteins known as enzymes. Grain that has gone through this process is referred to as "malt" . The Mash At this point, the brewer takes over. The malt is crushed and soaked in water between 145° and 155° F. This activates the enzymes that were produced during the malting process, and it converts the remaining carbohydrates into simple sugars. Types of Brewing Recipes For new homebrewers, all of this might seem a little daunting.

The good news is that if you use malt extract, the malting and mashing are already done for you. Malt extract recipes may require you to steep some grain in your recipe (like making tea with a tea bag). However, this is only to add complexity, flavor and color to your beer. All the fermentable sugar that you need comes from the extract. There are three levels of brewing recipes that are distinguished by how you work with grain: Extract Brewing is when you use malt extract for all of your fermentable sugars, and you steep other grains only for flavor and color. Partial Mash Brewing is when you make a small mash to get sugar out of the grain, but you still supplement your recipe with malt extract. All Grain Brewing recipes are more advanced. These recipes use only grains and no malt extract. Grain Glossary Here are a few of the basic types of grains and the styles of beer they're best for. Base Malts Base malts make up the majority of fermentable ingredients in beer recipes, usually 60-100%.

They're light in color and have a high enzyme concentration (which helps convert the starch to sugar.) Standard malted barley base malts go by the names Pale, Munich, Marris Otter or Pilsner. Malted wheat can also be used as a base malt, but it's typically mixed with at least an equal portion of a barley. These types of grain can be steeped in an extract recipe to provide a little complexity and flavor, but they're really most effective when used in a partial-mash or all-grain recipe. Malt Extract Malt Extract is base malt that has been mashed and condensed. Extract can be liquid or powdered, and comes in colors such as light, amber or dark. Extracts will also differ depending on which base malt they are derived from; you can make extract from Pilsner malt or malted wheat, for example. To get the most out of your extract, I recommend using light extract, and adding color (and flavor) by steeping other types of grains. Since liquid extract has less sugar per pound than dry extract, you should follow the recipe and not substitute one for the other. Crystal Malts Crystal malts are the most commonly used specialty grains for homebrewing.

They are gently roasted while wet, which converts most of the starch to sugar and cooks it a bit. The intensity of the roasting is indicated by the color and is measured in Lovibond (L). Crystal malts that are 10L or 20L are lightly roasted and will contribute an orange color and mild toffee flavors. If you want grains for an amber ale or a brown ale, malts that are 40L to 80L have the color and rich sweetness that you're looking for. Grains higher than 100L provide a very dark color and strong caramel flavor. You can steep crystal malts or use them in a partial-mash or all-grain recipe. Flaked Oats, Barley, or Wheat These are used in recipes to contribute a complex and silky mouthfeel as well as flavor. These grains are unmalted and pressed under hot rollers, which preserves the proteins that help with head retention and soft mouthfeel. The creamy texture of Guinness is attributed to flaked barley. Flaked oats are often used in oatmeal stouts and flaked wheat can be used in hefeweizens.

Since these grains are unmalted, they must be used in a partial-mash or all-grain recipe. There is not any benefit from steeping these in an extract recipe. Roasted Grains Dark roasted grains provide dark brown to black color and roasty coffee, cocoa, burnt and bitter flavors to the beer. They are cooked at higher temperatures than crystal malts and for a longer period of time. Like crystal malts, the intensity of the roast is measured in Lovibond, but these grains range from 350L for a chocolate malt to 500L for a black malt or roasted barley. Roasted grains give stouts and porters their characteristic dark color and rich flavor. The cooking strips all enzymes from roasted malts, but they can be used equally effectively in partial-mash and all-grain recipes as well as in extract recipes.

Question: What is converted into alcohol during brewing?
Answer: SUGAR