How to Brew Your First Beer
This document is intended to be distributed freely and may be copied for personal use.
Copyright © 2000 by John J. Palmer All Rights Reserved.
For a more thorough guide to homebrewing, see my complete book, How To Brew at www.howtobrew.com
These instructions are designed for the first-time Brewer. What follows can be considered an annotated recipe for a fool-proof ale beer. Why an ale? Because ales are the simplest to brew. There are two basic kinds of beer: ales and lagers. Ales can be brewed in a relatively short period of time at room temperature. Lagers require longer times (a month or more) and cold temperatures.
Brewing beer is simple and complicated, easy and hard. Compare it to fishing - sit on the end of the dock with a can of worms and a cane pole and you will catch fish. Going after a specific kind of fish is when fishing gets complicated. Brewing a specific kind of beer can get complicated too. There are many different styles of beer and many techniques to brew them.
Brewing a beer is a combination of several simple processes. First is the mixing of ingredients and bringing the solution (wort) to a boil. Second is the cooling of the wort to the fermentation temperature. Next the wort is transferred to the fermenter and the yeast is added. After fermentation, the beer is siphoned off the yeast sediment and bottled with a little extra sugar to provide the carbonation. These are simple steps but there are three important things to keep in mind every time you brew: Cleanliness, Preparation and Good Record Keeping.
Cleanliness - Cleanliness is the foremost concern of the brewer. Providing good growing conditions for the yeast in the wort also provides good growing conditions for other micro-organisms, especially wild yeast and bacteria. Cleanliness to prevent contamination must be maintained throughout every stage of the brewing process.
Preparation - Take the time to prepare your brewing area. Have the ingredients ready on the counter. Prepare your yeast. Have the ice bath ready to cool the wort when its done boiling. Make sure that all equipment is clean and ready to go before starting. Patience and planning are necessities.
Record Keeping - Always keep good notes on what ingredients, amounts and times were used in the brewing process. You need to be able to repeat good batches and learn from poor ones.
The following terms will be used throughout these instructions.
Ale - A beer brewed from a top-fermenting yeast with a relatively short, warm fermentation.
Alpha Acid Units (AAU) - A homebrewing measurement of hops that quantifies the amount of alpha acids (bittering agents) going into the beer before fermentation. Equal to the weight of hops in ounces multiplied by the percent of Alpha Acids.
Attenuation - The degree of conversion of sugar to alcohol and CO2.
Beer - Any beverage made by fermenting malted barley and seasoning with hops.
Cold Break - Proteins that coagulate and fall out of solution when the wort is rapidly cooled after the boil.
Conditioning - An aspect of secondary fermentation in which the yeast refine the flavors of the beer. Conditioning continues in the bottle.
Fermentation - The conversion of wort to beer, defined here as three parts, Lagtime, Primary, and Secondary.
Gravity - Like density, gravity describes the concentration of malt sugar in the wort. The specific gravity of water is 1.000 at 59F. Typical beer worts range from 1.035 - 1.055 before fermentation (Original Gravity). The finished beer gravity (FG) will range from 1.005 - 1.015, depending on the OG and type of yeast.
Hops - Hop vines are grown in cool climates and brewers make use of the cone-like flowers to add bitterness and balance the sweetness of the malt sugar. The dried cones are available in pellets, plugs, or whole.
Hot Break - Proteins that coagulate and fall out of solution during the wort boil.
Iodophor - An iodine-based sanitizing solution which does not require rinsing.
International Bittering Units (IBU) - A more precise method of measuring hop bitterness. An IBU is a measure of the amount of alpha acid in the beer after fermentation. Various equations have been devised to estimate the IBUs in a beer based on the AAUs and factors for percent utilization, wort volume and wort gravity.
Krausen (kroy-zen) - Used to refer to the foamy head that builds on top of the beer during primary fermentation. Also an advanced method of priming.
Lager - A beer brewed from a bottom-fermenting yeast and given a long cool fermentation.
Lagtime - The period of time from pitching the yeast until primary fermentation is evident. The lagtime should preferably be less than 12 hours.
Pitching - Term for adding the yeast to the fermenter.
Primary Fermentation - The high activity phase marked by the evolution of carbon dioxide and krausen. Most of the attenuation occurs during this phase.
Priming - The method of adding a small amount of fermentable sugar prior to bottling to give the beer carbonation.
Racking - The careful siphoning of the beer away from the trub.
Secondary Fermentation - A period of conditioning and settling of the yeast after primary fermentation and before bottling.
Trub (trub or troob) - The sediment at the bottom of the fermenter consisting of hops, hot and cold break material, and dormant (sometimes dead) yeast.
Wort (wart or wert) - The malt-sugar solution that is boiled with hops prior to fermentation.
Zymurgy - The science of Brewing and Fermentation.
Airlock - Several styles are available. Fill to the water line with water and cap it (if it has one). Airlocks prevent airborne contamination during fermentation.
Boiling Pot - Must be able to comfortably hold a minimum of 3 gallons; bigger is better. Use Aluminum, Stainless Steel or Ceramic- coated (enameled) Steel. If you use a new aluminum pot, don't use it bright-and-shiny; you may get a metallic off-flavor. Boil some water in it first.
Bottles - You will need 48 re-cappable 12 oz bottles. Use bottles that are thicker, like those used by microbreweries and imports. Twist-offs do not re-cap well. Used champagne bottles are ideal if you can find them.
Bottle Capper - Either Hand Capper or Bench Capper. Bench Cappers are more versatile and are needed for the champagne bottles, but are more expensive.
Bottle Caps - Both standard (crown) caps and oxygen-absorbing caps are available.
Bottle Filler - Rigid plastic (or metal) tube with spring loaded valve at the tip for filling bottles.
Bottle Brush - Necessary for initial thorough cleaning of used beer bottles.
Fermenter(s) - The 6 gallon food-grade plastic pail is recommended for beginners. These are very easy to work with. Glass carboys are also available, in 5, 6, and 7.5 gallon sizes.
Racking Cane - Rigid plastic tube with sediment stand-off.
Siphon/Hose - Available in several configurations, consisting of clear plastic tubing with optional Racking Cane and Bottle Filler.
Note on Siphoning:
Do not suck on the hose to start the siphon. This will contaminate the hose with Lacto Bacillus bacteria from your mouth. Fill the hose with sanitizing solution prior to putting it into the beer. Keep the end pinched or otherwise closed to prevent the solution from draining out. Place the outlet into another spare container and release the flow; the draining solution will start the siphon. Once the siphon is started, transfer it to your desired container.
Stirring Paddle - Food grade plastic paddle (spoon) for stirring the wort during boiling.
Thermometer - Obtain a thermometer that can be safely immersed in the wort and has a range of at least 40F to 150F. The floating dairy thermometers work well, as do the LCD dial thermometers.
Optional but Highly Recommended
Bottling Bucket - A 6 gallon food-grade plastic pail with attached spigot and fill-tube. The finished beer is racked into this for priming prior to bottling. Racking into the bottling bucket allows clearer beer with less sediment in the bottle. The spigot set-up is used instead of the Bottle Filler above, allowing greater control of the fill level and no hassles with a siphon during bottling.
Hydrometer - A hydrometer measures the relative specific gravity between pure water and water with sugar dissolved in it. The hydrometer is used to gauge fermentation by measuring one aspect of it, attenuation. Attenuation is the conversion of sugar to ethanol by the yeast. Water has a specific gravity of 1.000. Beers typically have a final gravity between 1.015 and 1.005. Champagnes and meads can have gravities less than 1.000, because of the large percentage of ethyl alcohol, which has a density of less than 1. By the way, hydrometer readings are standardized to 59F, since liquid gravity (density) is dependent on temperature. Temperature correction tables are usually sold with a hydrometer or are available from Chemistry Handbooks (ex. CRCs).
Here is a short table of corrections:
50F => -.0006
55F => -.0003
59F => 0
65F => +.0006
70F => +.0012
75F => +.0018
80F => +.0026
85F => +.0033
How To Use a Hydrometer
A hydrometer is a useful tool in the hands of an experienced brewer who knows what he wants to measure. Various books or recipes may give Original and/or Final Gravities (OG and FG) of a beer to assist the brewer in the evaluation of his success. For an average beer yeast, a rule of thumb is that the FG should be about one forth of the OG. For example, a common beer OG of 1.040 should finish about 1.010 (or lower). A couple points either way is typical scatter.
It needs to be emphasized that the stated FG of a recipe is not the goal. The goal is to make a good tasting beer. The hydrometer should be regarded as only one tool available to the brewer as a means to gauge the fermentation progress. The brewer should only be concerned about a high hydrometer reading when primary fermentation has apparently ended and the reading is about one half of the OG, instead of the nominal one forth. Incidentally, if this situation occurs, two remedies are possible. The first is to agitate or swirl the fermenter to rouse the yeastbed from the bottom. The fermenter should remain closed with no aeration. The goal is to re-suspend the yeast so they can get back to work. The alternative is to pitch some fresh yeast.
Hydrometers are necessary when making beer from scratch (all-grain brewing) or when designing recipes. But a first-time brewer using known quantities of extracts usually does not need one.
Commercial beer kits always provide 3-4 pounds of malt extract and the instructions ften say to add a couple more pounds of table sugar. Don't Do It! The resultant beer will have an unpleasant cidery taste. Use more malt extract instead. The following is a basic beer recipe for a Pale Ale:
Mild Pale Ale
5-7 pounds of hopped pale malt extract syrup. (OG of 1.038 - 1.053)
5 gallons of water
1-2 ounces of hops (if desired for more hop character)
2 packets of dry ale yeast, plus 1 packet for back-up.
3/4 cup corn sugar for priming.
This is a basic Pale Ale and quite tasty. You will be amazed.
Further descriptions of the ingredients follow.
Using malt extract is what makes homebrewing simple. Malt extract is the concentrated sugars extracted from malted barley. It is sold in both the liquid and powdered forms. The syrups are approximately 20 percent water, so 4 pounds of dry malt extract (DME) is roughly equal to 5 pounds of malt extract syrup. Malt extract is available in both the Hopped and Unhopped varieties. Munton & Fison, Alexanders, Coopers, Edme and Premier are all good brands. Read the ingredients to avoid added refined sugars which are often added to Light Beer-style kits.
Using Unhopped extract requires you to add 1-2 ounces of hops during the boil for bittering and flavor. Hops may also be added to the Hopped extracts towards the end of the boil to add more hop character to the final beer.
The rule of thumb is 1 pound of malt extract (syrup) per gallon of water for a light-bodied beer. One and a half pounds per gallon produces a richer, fuller-bodied beer. One pound of malt extract syrup typically yields a gravity of 1.034 - 38 when dissolved in one gallon of water. Dry malt will yield about 1.040 - 43. Malt extract is commonly available in Pale, Amber and Dark varieties, and can be mixed depending on the style of beer desired. Wheat malt extract is also available and more new extracts for specific beer styles (like Stouts) are coming out each year. With the variety of extract now available, there is almost no beer style that cannot be brewed using extract alone.
The next step in complexity for the homebrewer is to learn how to extract the sugars from the malted grain himself. This process, called Mashing, allows the brewer to take more control of producing the wort. This type of homebrewing is referred to as All-Grain brewing, but it will not be discussed in this document. Read my book, How To Brew if you are interested in this brewing technique.
The water is very important to the resulting beer. After all, beer is mostly water. If your tap water tastes good at room temperature, it should make good beer. If the water has a metallic taste, boil and let it cool before using to let the excess minerals settle out. A good bet for your first batch of beer is the bottled water sold in most supermarkets as drinking water. Use the 2.5 gallon containers. Use one container for boiling the extract and set the other aside for addition to the fermenter later.
This is an involved subject. There are many varieties of hops, but they can be divided into two main categories: Bittering and Aroma. Bittering hops are high in Alpha Acids (the main bittering agents), typically greater than 10 percent. Aroma hops are lower, around 5 percent. Several hop varieties are in between and are used for both purposes. Bittering hops are added at the start of the boil and usually boiled for an hour. Aroma (or Finishing) hops are added towards the end of the boil and are typically boiled for 15 minutes or less. Hops can also be added to the fermenter for increased hop aroma in the finished beer, called Dry Hopping, but this is best done during secondary fermentation. A mesh bag, called a Hop Bag, may be used to help retain the hops during the boil and make removal of the hops easier prior to fermentation. Straining or removal of the hops before fermentation is not absolutely necessary and is largely a matter of personal preference.
Beer recipes often include a hop schedule, with amounts and boil times specified. Sometimes recipes specify the hops in terms of AAUs or IBUs. AAUs are a convenient unit for specifying hop amounts when discussing hop additions because it allows for differences in the alpha acid percentages between hop varieties or within the same variety year to year.
For the purposes of this recipe, 7 AAUs are recommended for the Boil (60 minutes) and 4 AAUs for Finishing (15 minutes). This is assuming the use of unhopped malt extract; if you are using hopped extract, then only add the 4 AAUs for finishing. In this recipe, these amounts correspond to 22 IBUs for the boil, and 1 IBU for the finish. IBUs allow for variation in brewing practices between brewers, yet provide a means for targeting the same final hop bitterness level in the beers. This recipe is not very bitter. For more information on hop varieties and estimating IBUs, see my book, How To Brew
There are several aspects to yeast; it is the other major factor in determining the flavor of the beer. Different yeast strains will produce different beers when pitched to identical worts. Yeast is available in both liquid and dried forms, and for different types of ales and lagers. For the first-time brewer, a dried ale yeast is highly recommended. Some leading and reliable brands of dry yeast are Yeast Labs (marketed by G.W. Kent, produced by Lallemand of Canada), Cooper's, DanStar (produced by Lallemand), Munton & Fison and Edme.. Avoid using a no-name yeast packet that came taped to the top of a can of extract. You don't know how old it is.
Ale yeast are referred to as top-fermenting because much of the fermentation action takes place at the top of the fermenter, while lager yeasts would seem to prefer the bottom. While many of today's strains like to confound this generalization, there is one important difference, and that is temperature. Ale yeasts like warmer temperatures, going dormant below 55F (12C), while Lager yeasts will happily work at 40F. Using lager yeast at ale temperatures 65-70F (18-20C) can produce a mixed character, a slightly fruity tasting lager, referred to as California Common Beer, of which Anchor Steam Beer is the most notable example. For more information, see my book, How To Brew
Preparing Your Yeast
Dry Yeast needs to be re-hydrated before pitching; it will work much better. Once rehydrated, it can be "proofed" by adding a little bit of sugar to see if it is still viable.
1. Put 1 cup of warm (95-105F, 35-40C) boiled water into a sterile jar and stir in two packets of dry yeast.
2. Cover with plastic wrap and wait 15 minutes.
3. Boil one teaspoon of sugar in a little bit of water and let it cool.
4. Add this sugar to the re-hydrated yeast, cover, and place in a warm area out of direct sunlight.
5. After 30 minutes or so the yeast should be actively churning and foaming. This is now ready to pitch. If it is not showing signs of activity, then repeat the process with another packet.
Liquid yeast is often favored over dry yeast because of the greater number and variety of yeast strains available. Liquid yeast allows for greater tailoring of the beer to a particular style. Liquid yeast packets should be stored in the refrigerator to keep the yeast dormant and healthy until they are ready to be used. There are two types of liquid yeast package: those with inner nutrient packets and those without. The packages that contain an inner bubble of yeast nutrient (ie. a "smack pack") are intended to function as a mini-starter, but are really not adequate. All liquid yeast needs to be pitched to a starter wort to ensure adequate cell counts for a good fermentation. Smack packs must be squeezed and warmed to 80F at least two days before brewing. The packet will begin to swell as the yeast wake up and start consuming the nutrients. When the packet has fully swelled, it is time to pitch it to a starter.
Liquid Yeast Starter Procedure
1. To prepare a liquid yeast starter, dissolve 1/2 cup of DME into a pint of boiling water.
2. Boil it for a minute or two and let it cool to 75F (25C). Transfer the wort to a mason jar or other sanitized container.
3. Pour in the liquid yeast from the packet and add a quarter teaspoon of yeast nutrient.
4. Shake the Starter vigorously to aerate it and encourage yeast growth.
5. Let this sit in the same warm place until brewing time the next day. Some foaming or an increase in the white yeast layer on the bottom should be evident. The Starter process may be repeated to provide even more yeast to the wort to insure a strong fermentation. Most people prefer to pour off the excess liquid (beer) and only pitch the yeast slurry from the bottom of the jar.
The Wort and Oxygen
The use of oxygen in brewing is a double-edged sword. The yeast utilize oxygen in their growth processes, although they don't exactly breath. Boiling the wort drives out the dissolved oxygen, which is why aeration of some sort is needed prior to fermentation. Once the yeast use up all of the oxygen in the wort for growth and reproduction, they get down to the anaerobic business of turning sugar into alcohol and CO2 that we call fermentation. Prior aeration of the wort is the best way to ensure that there are enough yeast cells for a good fermentation.
Aeration of the wort can be accomplished several ways: shaking the container, pouring the wort into the fermenter so it splashes, or even hooking up an airstone to an aquarium air pump and letting that bubble for an hour. For the latter method, (which is popular) everything must be sanitized! Otherwise, welcome to Infection City. These instructions recommend shaking the starter and pouring/shaking the wort. More on this later.
On the other hand, if oxygen is introduced while the wort is still hot, the oxygen will oxidize the wort and this is a problem. This will cause oxidation of the beer later which can manifest as a wet cardboard taste after several weeks. The key to preventing oxidation is to not aerate when the wort is above 80F. In addition, if oxygen is introduced after the fermentation has started, it may not be completely utilized by the yeast and will later cause off-flavors.
This is why it is important to cool the wort rapidly to below 80F, to prevent oxidation, and then aerate it to provide the dissolved oxygen that the yeast need to help growth and reproduction. Cooling rapidly between 90 and 130F is important because this region is ideal for bacterial growth to be established in the wort. See the Cooling The Wort section for suggested methods.
Equipment Cleaning Tips
Clean all equipment after use as soon as possible. It is very easy to get distracted and come back to find the syrup or yeast has dried hard as a rock and the equipment is stained. If you are pressed for time, keep a large container with chlorine water handy and just toss things in to clean later.
Rinsing beer bottles immediately after use eliminates the need to scrub them. If your bottles are dirty or moldy, soaking and washing in a mild solution of chlorine bleach water for a day or two will soften the residue. Brushing with a bottle brush is a necessity to remove stuck residue. Dish washers are great for cleaning the outside of bottles and heat sanitizing, but will not clean the inside where the beer is going to go; that must be done beforehand. Sodium Percarbonate-based cleaners (like PBW, B-Brite, and One-Step) work very well for cleaning the bottles. Do not wash with scented dish detergents. This leaves a residue which you will be able to taste. Never use any scented cleaning agents, these odors can be absorbed into the plastic buckets and manifest in the beer. Lemon-Fresh scented Pinesol beer is not very good. Unscented mild liquid dishwashing detergents are acceptable for routine cleaning, just be sure to rinse the items thoroughly. Lastly, be aware that dishwasher rinse agents will destroy the head retention on your glassware. If you pour a beer with carbonation and no head, this is a common cause.
So far, sanitization of ingredients and equipment has been discussed but not much has been said about how to do this. The definition and objective of sanitization is to reduce bacteria and contaminants to insignificant or manageable levels. Sterilization is not really possible or practical. The starter solution, wort and priming solutions will all be boiled, so those are not a problem (usually).
One note - Do Not Boil the Yeast! You need them to be alive.
The most readily available sanitizing solution is made be adding 1 tablespoon of bleach to 1 gallon of water (4 ml per liter). A very popular sanitizer is Iodophor. Use 1 tablespoon per 5 gallons (4 ml/19 liters). Another excellent sanitizer is Star-San, from the makers of PBW. Use 1 fluid ounce per 5 gallons. The sanitizing solution can be prepared in the fermenting bucket. Immerse all of equipment - airlock, hoses, paddles, rubber stopper, fermenter lid and anything else contacting the beer. Let it sit for 20 minutes. Rinsing is not really necessary at this concentration, but you may want to rinse with boiled water to avoid any chance of off-flavors.
Ready to Begin?
Okay, we have covered equipment, ingredients and preparations. Are you ready to begin? Do you have everything cleaned and sanitized? Do you have your ingredients ready? You do not need to have your bottles cleaned and sanitized at this point, that step is about two weeks away. I will now walk you through the brewing processes.
Beginning the Boil
Bring 2 1/2 gallons water to a boil in a large pot. Meanwhile, re-hydrate the dry yeast if you have not done so already. When the water is boiling, remove it from the heat. Add all the malt extract to the hot water and stir until dissolved. Make sure there is no syrup stuck to the bottom of the pot. It is very important not to burn any malt stuck to the bottom when the pot is returned to the heat. Burnt sugar tastes terrible.
The following stage is critical. The wort has a tendency to boil-over and needs to be watched continuously. If you are adding bittering hops, do so now. Return the pot to the heat and bring to a rolling boil, stirring frequently. Start timing the hour.
A foam may start to rise and form a smooth surface. This is good. If the foam suddenly billows over the side, this is a boil-over (Bad). The liquid is very unstable at this point and remains so until it goes through the Hot Break (when the wort stops foaming). This may take 5-20 minutes. The foaming can be controlled by lowering the heat and/or spraying some water on the surface from a spray bottle. Try to maintain a rolling boil.
Continue the rolling boil for the remainder of the hour. Stir occasionally to prevent scorching. There may be a change in color and aroma and there will be hot break particles floating in the wort. This is normal.
If you are adding the finishing hops, do so during the last fifteen minutes. Add some more during the last five minutes if more hop aroma is desired. This provides less time for the volatile oils to boil away.
Cooling the Wort
At the end of the boil, it is important to cool the wort quickly. While it is still hot, (above 140·F) bacteria and wild yeasts are inhibited. But it is very susceptible to oxidation damage as it cools. There are also sulfur compounds that evolve from the wort while it is hot. If the wort is cooled slowly, di-methyl sulfide will continue to be produced in the wort without being boiled off; causing off-flavors in the finished beer. The objective is to rapidly cool the wort to below 80·F before oxidation or contamination can occur.
Rapid cooling also forms the Cold Break. This is composed of another group of proteins that need to be thermally shocked into precipitating out of the wort. Slow cooling will not affect them. Cold break, or rather the lack of it, is one cause of Chill Haze. When a beer is chilled for drinking, these proteins partially precipitate forming a haze. As the beer warms up, the proteins re-dissolve. Only by rapid chilling from near-boiling to room temperature, will the cold break proteins permanently precipitate and not cause chill haze. Chill haze is usually regarded as a cosmetic problem. You cannot taste it.
To cool the wort effectively, place the pot in a sink or tub filled with cold/ice water that can be circulated around the hot pot. While the cold water is flowing around the pot, gently stir the wort in a circular pattern so the maximum amount of wort is moving against the sides of the pot. The wort should cool to 80F in about 20 minutes. Be sure that your thermometer is sanitized before putting it in the wort.
Pour the reserved 2.5 gallons of water into the sanitized fermenter. Pour the cooled wort into it, allowing vigorous churning and splashing. Oxidation of the wort is minimal now and this provides the dissolved oxygen that the yeast need to reproduce. It is best for the beer if the wort temperature when the yeast is pitched is the same as the fermentation temperature. In other words, the wort should not be appreciably warmer than the room it is going to be fermented in. For Ale yeasts, the preferred fermentation temperature range is 65-75F. High initial wort temperatures or fermentation temperatures higher that 80F can cause the yeast to produce noticeable off-flavors.
Note: Do not add commercial ice directly to the wort to cool. Commercial ice harbors lots of dormant bacteria that would love a chance to work on the new beer. If you want, you can freeze a bottle of water and immerse that in the wort, but the outside of the bottle needs to be sanitized before immersion.
Pitching the Yeast
If the Yeast Starter is not foaming or churning, use the backup yeast. Repeat the re-hydration procedure and then pitch the Yeast Starter into the beer, making sure to add it all. Put the fermenter lid in place and seal it. Do not put the airlock in quite yet. Place a piece of clean plastic wrap over the hole in the lid and cover it with your hand.
With the fermenter tightly sealed, pick it up, sit in a chair, put the fermenter on your knees and shake it several minutes to churn it up. This mixes the yeast into the wort and provides more dissolved oxygen that the yeast need to grow. Wipe off any wort around the hole with a paper towel that is wet with bleach water and place the sanitized airlock and rubber stopper in the lid. The airlock should be filled to the line with water.
Active fermentation should start within 12 hours. If no activity is seen in 24 hours, then add more yeast.
Put the fermenter in a protected area like the bathtub. If foam escapes it will run down the drain and is easy to clean. The temperature here is usually about the most stable in the house. Animals and small children are fascinated by the smell and noises from the airlock, so keep them away.
The airlock should be bubbling in twelve hours. Maintain a consistent temperature if possible. A fluctuating temperature strains the yeast and could impair fermentation. If the temperature drops overnight and the bubbling stops, simply move it to a warmer room and it should pick up again. The yeast does not die, it merely goes dormant. You may need to swirl the fermenter to rouse the yeast off the bottom, but do not shake the fermenter at this stage though.
Bottom line- if the temperature deviates too much or goes above 80F, the fermentation can be affected, which then affects the flavor. If it goes too low, the ale yeast will go into hibernation.
The fermentation process can be very vigorous or slow; either is fine. The secret to a good fermentation is in providing enough active yeast. Fermentation time is a sum of several variables with the most significant probably being temperature. It is very common for an ale with an active ferment to be done in a short time. It could last a few days, a week, maybe longer. Any of the above is acceptable. Two to three days at 70F is typical for the simple ale being described here.
If the fermentation is so vigorous that the foam pops the airlock out of the lid, just rinse it out with sanitizer and wipe off the lid before replacing it. Contamination is not a big problem at this point. With so much coming out of the fermenter, not much gets in. Once the bubbling slows down however, do not open the lid to peek. The beer is still susceptible to infections, particularly anaerobic ones like Lacto Bacillus, found in your mouth. The beer will do just fine if left alone for a minimum of two weeks.
The fermentation of malt sugars into beer is a complicated biochemical process. It is more than just the conversion of sugar to alcohol, which can be regarded as the primary activity. Total fermentation is better defined as three phases, the Adaptation or Lagtime phase, the Primary or Attenuative phase and a Secondary or Conditioning phase. The yeast do not end Phase 2 before beginning Phase 3, the processes occur in parallel, but the conditioning processes occur more slowly. As the majority of simple sugars are consumed, more and more of the yeast will transition to eating the larger, more complex sugars and early yeast by-products. This is why beer (and wine) improves with age to a degree, as long as they are on the yeast. Beer that has been filtered or pasteurized will not benefit from aging.
Immediately after pitching, the yeast start adjusting to the wort conditions and undergo a period of high growth. The yeast use any available oxygen in the wort to facilitate their growth processes. They can use other methods to adapt and grow in the absence of oxygen, but they can do it much more efficiently with oxygen. Under normal conditions, the yeast should proceed through the adaptation phase and begin primary fermentation within 12 hours. If 24 hours pass without apparent activity, then a new batch of yeast should probably be pitched.
The primary or attenuative phase is marked by a time of vigorous fermentation when the gravity of the beer drops by 2/3-3/4 of the original gravity (OG). The majority of the attenuation occurs during the primary phase, and can last anywhere from 2-6 days for ales, depending on conditions.
A head of foamy krausen will form on top of the beer. The foam consists of yeast and wort proteins and is a light creamy color, with islands of green-brown gunk that collect and tend to adhere to the sides of the fermenter. The gunk is composed of extraneous wort protein, hop resins, and dead yeast. These compounds are very bitter and if stirred back into the wort, could result in harsh aftertastes. Fortunately these compounds are relatively insoluble and are typically removed by adhering to the sides of the fermenter as the krausen subsides. Aftertastes are rarely, if ever, a problem.
As the primary phase winds down, a majority of the yeast start settling out and the krausen starts to subside. If you are going to transfer the beer off of the trub and primary yeast cake, this is the proper time to do so. Take care to avoid aerating the beer during the transfer. At this point in the fermentation process, any exposure to oxygen will only contribute to staling reactions in the beer, or worse, expose it to contamination.
Many canned kits will advise bottling the beer after one week or when the bubbling stops. This is not a good idea because the beer has not yet gone through the Conditioning phase. At this time the beer would taste a bit rough around the edges (e.g. yeasty flavors, buttery tones, green apple flavors) but these will disappear after a few weeks of conditioning.
The reactions that take place during the conditioning phase are primarily a function of the yeast. The vigorous primary stage is over, the majority of the wort sugars have been converted to alcohol, and a lot of the yeast cells are going dormant - but some are still active.
The Secondary Phase allows for the slow reduction of the remaining fermentables. The yeast have eaten most all of the easily fermentable sugars and now start to turn their attention elsewhere. The yeast start to work on the heavier sugars and clean up some of the byproducts they produced during the fast-paced primary phase. However, it is often a good idea to get the beer off of the trub during the conditioning phase, especially if the beer is going to sit on the trub for a long period of time, like in the case of lager beer. See my book, How To Brew for more information on lager brewing.
Under some conditions (like excessively long times and/or high temperatures), the yeast will also consume some of the compounds in the trub. The consumption of these compounds can produce several off-flavors. In addition, the dormant yeast on the bottom of the fermenter will begin excreting more amino and fatty acids. If the post-primary beer is left on the trub and yeast cake for too long (more than about three weeks in some cases) soapy flavors may become evident. Further, after very long times in worts with poor nutrient levels, the yeast begin to die and break down - autolysis, which produces rubbery, sulfury tastes and smells. For these reasons, it can be important to get the beer off of the trub and dormant yeast during the conditioning phase.
There has been a lot of controversy within the homebrewing community on the value of racking ales to secondary fermenters. While there is no question in the case of lagers, many seasoned homebrewers have declared that there is no real taste benefit for ales and that the dangers of contamination and the cost in additional time are not worth what little benefit there may be. For your first beer, I will advise you to use only a single fermenter until you have gained some experience with racking and sanitation.
Leaving an ale beer in the primary fermenter for a total of 2-3 weeks versus one when using single stage fermentation (i.e. not using a second fermenter) will provide time for the conditioning reactions and improve the finished beer. The extra time will also let more sediment settle out before bottling, resulting in a clearer beer and easier pouring.
Using Secondary Fermenters (Optional)
Using a two stage fermentation requires a good understanding of the fermentation process. At any time, racking the beer can adversely affect it because of potential oxygen exposure and contamination risk. Racking the beer off the yeastbed before the primary fermentation phase has completed can result in a stuck or incomplete fermentation.
The following is a general procedure for using a secondary fermenter.
1. Allow the Primary Fermentation stage to wind down. This will be 2 - 6 days after pitching when the bubbling rate drops off dramatically to about 1-5 per minute. The krausen will have started to settle back into the beer.
2. Using a sanitized siphon (no sucking or splashing!), rack the beer off the trub into a another clean fermenter and affix an airlock. The beer should still be fairly cloudy with suspended yeast.
Racking from the primary may be done at any time after primary fermentation has more-or-less completed. (Although if it has been more than 3 weeks, you may as well bottle.) Most brewers will notice a brief increase in activity after racking, but then all activity may cease. This is very normal, it is not additional primary fermentation per se, but just dissolved carbon dioxide coming out of solution due to the disturbance. Fermentation (conditioning) is still taking place, so just leave it alone. A minimum useful time in the secondary fermenter is two weeks. Overly long times in the secondary (for light ales- more than 6 weeks) may require the addition of fresh yeast at bottling time for good carbonation. Always use the same strain as the original. This situation is usually not a concern.
Priming & Bottling
This beer will be ready to bottle in two or three weeks when primary fermentation has completely stopped. There should be few, if any, bubbles in the airlock. The flavor won't improve by bottling any earlier. Some books recommend bottling after the bubbling stops or in about 1 week. It is not uncommon for fermentation to stop after 3-4 days and begin again a few days later due to a drop in temperature. If the beer is bottled too soon, the beer will become over-carbonated and the pressure may exceed the bottle strength. Exploding bottles are a disaster.
After the bottles have been cleaned with a brush, they need to be sanitized. Immerse them in sanitizing solution or run them in the dishwasher with the heat on. If immersing, allow the bottles to drain completely before use. Rinsing should not be necessary, but if you do, only use water that has been boiled. Hot tap water is not necessarily sanitized. Also sanitize the priming container, siphon unit, stirring spoon and bottle caps. But do not heat the bottle caps, as this may ruin the gaskets or tarnish them.
Preparing the Priming Solution
Some books recommend adding 1 tsp. sugar to each bottle for priming. This is not recommended because it is time consuming and not precise. Bottles may carbonate unevenly and explode. Instead, boil 3/4 cup of corn or table sugar, or 1 and 1/4 cup dry malt extract in some water, let it cool, and add it to the whole batch. Here are two ways to add it, I recommend the first:
1. Pour the priming solution gently into a sanitized Bottling Bucket, don't let it splash. Then use a sanitized siphon to transfer the beer into the sanitized bottling bucket. Place the siphon outlet beneath the surface of the priming solution as it fills to prevent aeration. Do not allow the beer to splash as you don't want to add oxygen to your beer at this point. Keep the intake end of the racking tube an inch off the bottom of the fermenter to leave the yeast and sediment behind. See Note on Siphoning.
2. Open the fermenter and gently pour the priming solution into the beer. Stir the beer gently with a sanitized spoon, trying to mix it in evenly while being careful not to stir up the sediment. Wait a half hour for the sediment to settle back down and to allow more diffusion of the priming solution to take place. Then siphon to your bottles.
Filling Your Bottles
Place the fill tube of the siphon unit or bottling bucket at the bottom of the bottle. Fill slowly at first to prevent gurgling and keep the fill tube below the waterline to prevent aeration. Fill to about 3/4 inch from the top of the bottles. Place a sanitized cap on the bottle and cap. Inspect every bottle to make sure the cap is secure.
Carbonation will take about two weeks; age the bottles somewhere out of direct sunlight. Aging for one month will improve the flavor considerably, but one week will do the job of carbonation for the impatient.
Different beer styles benefit from different lengths of bottle conditioning. Generally, the higher the Original Gravity, the longer the conditioning time to reach peak flavor. Small beers like 1.035 Pale Ales will reach peak flavor within a couple weeks of bottling. Stronger/more complex ales, like Stouts, may require a month or more. Very strong beers like Doppelbocks and Barleywines will require 6 months to a year before they condition to their peak flavor. (If oxidation doesn't take its toll first. I have had some pretty awful year old barleywines.) When bottling your first few batches, its a good idea to set aside a six pack and leave it for a time. It is enlightening to taste a homebrewed beer that has had two months to bottle condition and compare it to what the batch initially tasted like.
Other Storage Considerations
Two common questions are, "How long will a homebrewed beer keep?" and "Will it spoil?" The answer is that homebrewed beer has a fairly long storage life due to the presence of the yeast. Depending on the style and original gravity, the beer will keep for more than a year. I occasionally come across a year-old six pack that I had forgotten about and it tastes great. Of course, there are other cases when that year-old six pack has gotten very oxidized in that time and tastes pretty bad. It really depends on how careful you were with the bottling - Quality in, Quality out.
Finally, it is important to keep the beer out of direct sunlight, especially if you use clear or green bottles. Exposure to sunlight or fluorescent light will cause beer to develop a skunky character. It is the result of a photo-chemical reaction with hop compounds and sulfer compounds. Contrary to popular belief, this is not a character that Heineken, Grolsch, and Molson strive for in their beer. It is simply a result of poor handling by retailers, and storing them under fluorescent lighting. Other beers like Miller High Life don't boil hops with the wort but instead use a specially processed hop extract for bittering which lacks the compounds that cause skunking (and flavor). Brown bottles are best unless you make a point of keeping your beer in the dark.
Drinking Your First Homebrew
One final item that nobody ever remembers to tell new brewers until it's too late is: "Don't drink the yeast layer on the bottom of the bottle."
People will say, "My first homebrew was pretty good, but that last swallow was terrible!" or "His homebrew really gave me gas" or "It must have been spoiled, I had to go to the bathroom right away after I drank it."
Welcome to the laxative effects of live yeast!
When you pour your beer from the bottle, pour it slowly so you don't disturb the yeast layer. With a little practice, you will be able to pour out all but the last quarter inch of beer. The yeast layer can harbor a lot of bitter flavors. It's where the word "Dregs" came from.
Some Things to Watch out for:
Contamination of beer can happen at any stage of the brewing process. Some are not readily apparent. But any problem that can be easily drank will not cause physical harm. By the way, it is absolutely impossible to produce poisonous methyl (wood) alcohol when brewing beer. A few infections that may cause severe gastric distress will first be noted by their appalling smell. Here are some warning signs:
1. Mold floating on top of the fermenting beer. Toss it.
2. The beer has slimy strands in it. This is a sure sign of Lacto infection. Toss it.
3. The bottled beer has a milky layer at the top and/or small residue bumps clinging to the sides of the bottle neck in the airspace. This is a bacterial infection. The beer will smell rotten and taste nasty. Do not confuse this with the dew that condenses near the bottle cap; the dew is normal. Also, Priming with DME will leave a protein ring around the top of the bottle, just like what is left on the sides of the fermenter. This is also normal.
4. The bottled beer has a very sweet smell, like molasses. This is a sign of an Aceto (acetic) infection. The beer is on its way to turning into malt vinegar. Malt vinegar is good, but not what was intended.
5. The bottled beers are getting worse with time, a stale, cardboard-like or sherry-like flavor is becoming noticeable. This is a symptom of oxidation. Drink the beers sooner and try to avoid splashing the hot wort next time.
6. A skunk-like or cat-musk smell. The beer is light struck. Always store beer in a dark or shaded area.
How To Brew by John Palmer
The comprehensive homebrewing book that covers everything you need to know to brew your beer right the first time, whether you are brewing with extract or all-grain. Step by step instructions and illustrations are provided for each brewing method.