Beer/Brewing 101 Fermentation
Intro
Ingredients
The Brewing Process
Malting and Mashing
The Boil and Beyond
The previous articles have gotten us to the point of getting our wort into the fermenter. This is where the magic start and we turn hopped sugary liquid into beer. This is when it technically becomes beer. Once again I will give this a good overview to impart a good understanding without trying to get too technical. At the end of the last article we had chilled the wort and transferred it into the fermenter so we will pick things up from there.
Once the chilled wort is in the fermenter we want to get it sealed from the outside air, in most cases, and get the yeast pitched into it. This is to prevent getting infections in the beer. Many types of wild yeast and bacteria are carried through the air and can spoil the beer. If they get in and take hold they will cause spontaneous fermentation and produce off flavours in almost all cases. There are beers that are made this way, Lambics, intentionally but this is not a common method. The other exception to this is beer produced in open fermenters. This relies on pitching active yeasty quickly so it takes hold before wild yeasts and bacteria can take hold. Open ferments are often done in sterile/sanitary room with filtered air like Anchor Brewery do.
Once the yeast is in the wort it can take anything from a couple of hours to a couple of days before you can see the action starting to happen. Depending on the yeast you wil see varying sizes of foam, called krausen, on top of the, what we can now call, beer. This is the result of the activity of the yeast. As they eat the sugars they produce C02 and alcohol. A typical ale fermentation will take 3-7 days and a lager 1-2 weeks. During the fermentation the brewer will take measurements with a hydrometer or refractometer to check how much sugar is left to be fermented. Once enough of the sugars have been eaten the beer may be filtered or put into additional steps for conditioning. A normal conditioning would involve dropping the beer to very ow temperatures for a period of time. This helps to drop out yeast and other things in the beer and also helps it condition faster. At this stage hops may also be added into the fermenter to get even more hop aroma. This is called dry hopping and is typically used in beers like IPAs.
Once fermentation and any conditioning is completed it’s time to package the beer. The two main packages are kegs and bottles. At this stage there is one main decision left to be made. Natural or forced carbonation? Natural carbonation requires the addition of extra sugars into the package. The remaining yeast in the beer will ferment this leaving C02 in the finished beer. Forced carbonation involves forcing C02 from an external source into the beer. If natural carbonation is used it will normally take around two weeks until the beer is ready.
That is fermentation and completes the brewing process. For my next series I may run through major beer styles. I hope you have enjoyed these posts.
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Beer/Brewing 101 The Boil and Beyond
Previous posts in this series:
Intro
Ingredients
The Brewing Process
Malting and Mashing
Now that the mash is completed and we have our wort, sugary and malty liquid, in the kettle it’s time to start the boil. There are two main reasons for boiling the wort. One is isomerise alpha acids from the hops to produce the bitterness in the beer. The other main reason is to sanitise the wort. At this point in the brewing process there will be all kinds of wild yeast and other bugs hanging around. We boil, typically, for 60-90 minutes killing as good as all bugs that are present. There are other effects and benefits from the boil but these are the primary reason it is performed.
The typical boil is 60 to 90 minutes. It is generally considered that 60 minutes is enough time to effectively kill any wild yeast or other bugs that are in the beer. Boils can be extended out to 90 minutes and in some cases beyond to produce specific flavours in beer. Some people will call the flavours produced by a longer boil as caramel type flavours. Although the flavours are similar no caramelisation will take place in the boil. The boil just doesn’t get hot enough. However, maillard reactions will happen that can give caramel like flavours. It’s beyond the scope of this piece to go into maillard reactions and their difference to caramelisation but it’s easy to find info on Google if you want to dig deeper.
Hops can be added at a number of times during the boil. In general hops that are added at the start of the boil, with 60-90 minutes to go, are for adding bitterness to beer. These will generally be a variety with high alpha acids and with little regard to flavour and aroma. This does vary with style but is a good general rule. Hops added between the 20-40 minutes remaining in the boil mark are generally considered flavour additions. The earlier in a boil hops are added the more alpha acid you get for bitterness but you also boil off more of the oils that produce flavour and aroma. Hops added in the last 15 minutes of the boil are considered aroma additions. The hops chosen for flavour and aroma additions will be chosen based on those characteristics of the hops and will generally have little regard for the bittering qualities.
In some beers, common in IPA and American style pale ales, hops will be added at the completion of the boil. These hops will contribute very little to bitterness but can have a large impact on the aroma and flavour of the beer. The wort takes some time to cool so the hops will have the chance to add flavour and aroma.
At the end of the boil the wort will normally be whirlpooled. This can happen in the main kettle or after transfer to another special whirlpool vessel. The whirlpool is exactly what it sounds like and it is done to remove hops and other debris from the wort. After whirlpooling the matter will generally be in a clump in the centre of the kettle and clean wort can be extracted from the outside. There are some breweries that use other methods instead of or in combination with whirlpooling like filters but whirlpooling is common to most breweries.
Once we have extracted the hops and other debris from the wort we need to get it chilled as quickly as possible. Between the end of the boil and when the yeast is pitched the wort is very susceptible to infection so you want to get it cool and have the yeast pitched as quickly as possible. The temperature the wort will be chilled to depends on the style of beer being produced. Typically for an ale you will chill to about 18C and around 10C for a lager but there is a lot of variation for different beers. Most commercial breweries use some form of counter flow chiller normally in the form of a plate chiller. The basic theory is that hot wort enters pipe at one end. Around that pipe is a jacket that has chilled water flowing in the opposite direction. Once the wort exits the pipe at the other end the chilled jacket has reduced it’s temperature to the required pitching temperature. There are a number of other methods used but some variation of this is the most common.
The chilled wort will be transferred via the chiller into the fermenter to have the yeast pitched and to begin fermentation. At this point extra oxygen may also be added to the beer but we will cover fermentation in more depth in the next post. Don’t forget to check out How to Brew by John Palmer it’s my main source for brewing information.
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Beer/Brewing 101 – Malt and Mashing
Previous posts in this series:
The Brewing Process
Ingredients
Other than water this ingredient is the major part of beer. I decided not to do an individual post on water for now. Although water is very important, unless you are really into it it can be pretty dense and if you are starting to brew yourself there are probably a lot of other things you want to know about and study before you get to water chemistry.
Malt, most commonly malted barley is where we get the sugar for the yeast to ferment. Before it gets to the brewer it malted by a maltster. Malting involves taking the barley grains dampening them and keep them at a constant temperature until they just start to sprout. Once the malt starts to sprout it is kilned to stop the growing but leave the starchy sugars available to the brewer once the grain is cracked open. The kilning temperatures and time will vary depending on the type of malt being made. A Munich malt for example would be kilned at a higher temperature and for longer than a pilsener malt. I will go into more detail on malt and it’s production in another post but if you want something to read now check out this article.
The malt, usually a combination of malts for colour and flavour, are cracked open in a mill. Usually not crushed to flour but cracked open so the starchy sugars inside can contact with hot water in the mash. Some breweries, Coopers is an example, do crush to flour and have a mash filter rather than a lauter tun but this is not common. Once the grain has been cracked it is fed into the mash tun. This is a large insulated vessel that can hold it’s temperature. On the commercial scale this is often a large steam jacketed stainless steal vessel. On the home brewing scale some form of esky/drink cooler is common. Hot water is now added to the grain at a typical ratio of around 2.5l of water per kg of grain. Once again this can vary significantly. On a typical single infusion mash once the water and grain have been added and stirred it will be held at a temperature of around 66C. If you wanted to make a more fermentable wort you would aim for a lower temp and if you wanted to make a less fermentable and thicker finished beer you would aim for a higher temperature. Different enzymes work more effectively at different temperatures resulting in a different mouthfeel of the finished beer. You can find a good reference for further detail here.
Some brewers also employ multi temperature mashes. The mash will be held at a range of temperatures for varying lengths of time and slowly warmed. This can be done by direct heating the mash, adding more and hotter water or by a technique known as decoction mashing. In decoction mashing a calculated portion of the mash is removed from the main mash and brought to boiling then added back to the main mash to raise the overall temperature. These techniques were originally employed when maltsters couldn’t do as good a of a job modifying malt. Now days with heavily modified malts they are generally not required. However, they are traditional and some would argue vital to reproducing flavours of certain beer styles. I don’t have enough experience with these techniques to comment authoritatively so will leave you to decide this for yourself.
Grain Bed
The mash normally lasts for between 30 and 90 minutes. During this time a range of enzymes go to work chopping up the long chain starchy sugars from the grain into simpler sugars the yeast will be able to digest. The enzymes are already present on the malt and different enzymes will perform better and produce different results depending on the temperature of the mash. The liquid is then drained via a false bottom, manifold or similar device to prevent the grain from getting out of the mash vessel. This can happen in the mash tun it’s self or the whole mash can be transferred to a lauter vessel. While draining the wort the brewer would normally sparge to get all the sugars from the grain. The most common way in commercial brewing is to add water to the top at the same rate you are taking wort from the bottom. On home brewing scales it is also common to drain the whole mash then dump more water on top and drain again.
This liquid will be drained into a kettle and we now have our wort, malty sugary liquid, ready to boil. In the next installment we will cover the boil, why we do it and what happens there. Please leave a comment if you have any thoughts or questions.
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Beer/Brewing 101 – The Brewing Process
In this instalment of brewing 101 I am going to go over the entire brewing process. You can see the previous post here. We will go from water, malt, hops and yeast and make some beer. This will, once again, be an overview of each process. Once I get through the broad overviews the plan is to go back and cover the parts in more detail. This may be in specific posts or as part of covering a style.
The first step is to make the wort. The wort is the base of the beer before fermentation. To do this we first take the malted barley and crush it in a mill. We are just cracking open the grains and not pounding them into flour. This allows us access to the starchy sugars in the grain but leaves the husk intact to act as a filter. The grain is then mixed in the mash tun with hot water at a ratio of around 2-3l per kg of grain. A basic single step mash will be held at around 66C for around an hour. More complicated mashes with multiple temperature rests at different temperatures can be done to achieve particular results but are not as common as single infusions. The mash allows enzymes to break up the starches in the grain and convert them into more simple sugars the yeast can consume.
At the end of the mash the liquid, now called wort is transferred to the kettle. A kettle is a large pot/vat that the wort will be boiled in. While emptying the liquid from the mash tun more hot water will be added to rinse the grain and get all available sugars, this process is called sparging.
Once in the kettle the wort is brought to a boil. The boil has two main purposes in brewing. One reason is to sanitise the wort and kill of anything that may infect and spoil the beer. The next reason is where the hops come in. The wort will be boiled for normally 60-90minutes. During the boil hops will be added at different times. Additions of hops in the 45-90 minute are, primarily, to provide bittering. The alpha acids from the hops are dissolved into the solution and this provides the bitterness. Hops added in the time from will add little to aroma or flavour as the oils that come from the hops will be boiled off. Additions of hops in the 0-30 minute range are the flavour and aroma additions. The closer to the end of the boil the more aroma you will get but the less bittering character. This is why there is normally a range of additions across the length of the boil depending on the style.
Once the boil is completed the wort need to be cooled. It needs to be cooled as quickly as possible to avoid reactions that can cause off flavours in the beer. This is not always the case but is the normal process in brewing. A typical way of doing this is to run the hot wort through pipes that are jacketed by another larger pipe. In the outside pipe you run refrigerated water in the opposite direction. This is called a counterflow chiller. There are also plate chillers that work on a similar principle and immersion chillers that involve submerging cool pipes into hot wort. Whilst not the only method of chilling these are the most common.
After or normally during the cooling phase the wort is transferred to the fermenter. At this point the wort may be oxygenated or aerated to assist the yeast. The yeast which can be in a dry powder like or liquid for is now added to the fermenter and the fermenter sealed to prevent wild yeast or bacteria getting in. However, carbon dioxide will need to escape so we need a air lock. Commonly this is a hose from the top of a fermenter into a bucket of sanitised liquid. This can take many forms but the hose and bucket is common.
Now the yeast goes to work eating all the sugar and producing alcohol and C02. This process can take anywhere from three days to weeks depending on how high in alcohol the beer and the style of beer. Typically lagers and high alcohol beers take longer. Fermentation of ales is normally at 18-22C and lagers at 8-12C. For some styles of beer, like IPA, hops can also be added into the fermenter to add extra aroma to the beer, this is called dry hopping. Once fermentation is complete and the yeast have eaten all the sugar the beer may be cold conditioned or lagered. This means keeping the beer at a very low temperature, as close to freezing as possible, for an extended period. This can help drop yeast and other compounds that can cause off flavours out of the beer. Almost all lagers will be, unsurprisingly, lagered but some ales will be also. Beer may be filtered also at this time.
Once there process are complete it will be packaged into kegs, bottles or cans. Most commonly the beer will be force carbonated at this time by taking C02 and forcing it into the beer. However, some brewers like Coopers and Little Creatures will add a little fermentable material and a little extra yeast and allow it to ferment again the bottle/keg. This produces the carbonation naturally but takes a little longer. There are other carbonation methods but these are the most common.
That is how beer is made. This is a basic description that does skip over a lot of detail and uses some language that isn’t technically accurate so as to make it’s point simply. I will go into further detail over the course of this series. If you want something else to read now you should check out “How to Brew” by John Palmer. It’s a great book and a really good starting point to learn about how beer is made.
Please let me know in the comments if you have any questions. I would love to hear what people think and use it to guide the series.
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Beer/Brewing 101 – Ingredients
So this is where we start with brewing 101. Please comment or contact me if you find any errors in this. I know brewing reasonably well but I’m not a brewing scientist and I’m certainly not infallible. I’m going to do a summary of the main brewing ingredients. There are lots of variants and they won’t all be covered here, hopefully I will cover most variations over this course of these posts.
The primary ingredient is water. Kind of obvious but still very important. Water can have a much bigger impact than you would expect on finished beer. Water is the reason pilsener came from the Czech Republic and porters came out of London. Without going into specifics at this time the mineral make up in water affect the expression of different flavours and mouthfeel. You actually want some minerals in all brewing water for the yeast and for some styles you want pretty hard water. I will go into this in more detail when I do a post on water later on.
The next major ingredient is malt or malted grain. This is mostly barley but wheat is also common. Other grains are used but are rare in comparison to barley and wheat. Barley is the most common as it has a husk which makes it bad for bread and many other products but the husk is an asset for the mashing process in making beer. The mash will be covered soon. Malted grains are grains that have been heated in a moist environment until they just start to sprout. This releases starchy sugars from the grain. Once it starts to sprout it is roasted at high temperatures to stop the sprouting and to change flavour. The grain can be roasted to different levels to add colour and flavour. The malt provides the fermentable sugar that the yeast will turn into alcohol and C02.
The third of the four main ingredients is hops. Hops primary purpose is to provide bitterness to the beer. Without hops beer would be very sweet and not very drinkable. Historically many things have been used to provide bitterness but hops are used almost exclusively now days. Hops also provides flavour and aroma to the beer. There are infinite varieties of hops that are suited to different uses. Some hops can provide lots of bitterness but are low in flavour and aroma an some will do the reverse. They can do any and all combinations of these things.
Next we have the last of the main ingredients, yeast. The yeast is what eats the sugars and turns it into alcohol and C02. There are many varieties of yeast that will give distinctly different flavours to your beer. However, they can be roughly grouped into two basic types. There is ale yeast and lager yeast. Ale yeast works at higher temperatures, typically 18-22C, and produces more esters and fruity flavours. Lager yeast typically works at lower temperatures, typically 8-12C, and produces cleaner crisper flavours.
There are many other ingredient that are used in beer. Just malt wise there are many varieties with different levels of roasting, caramelised and even smoked malts. Various sugars are also used. This is often seen as a bad thing but in the right beer and used properly it can have a great impact on beer. Honey and fruit are becoming more common. I’m not a fan of them in general but they seem to be becoming popular. There is even a brewery in the USA using cedar tips for bittering so the possibilities are endless.
I was going to make this post an overall summary but it’s getting a little long so I will leave at an ingredients summary and get into the brewing process in the next post. My main reference is How To Brew by John Palmer. It’s a great book for free online or buy the updated dead tree edition.
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Beer/Brewing 101 Introdcution
I figure there are probably lots of beer lovers and geeks out there that don’t really know how their beer is made. Not everyone comes from a background of home or commercial brewing. Many that do don’t get past the Cooper’s kits. I intend to go through a basic overview of the brewing process. I don’t want to go too deep but will provide links for those that wish to go further. I don’t have a brewing science degree or anything but I have learnt a fair bit over the years. If you find mistakes please let me know. My main learning about brewing was from the book “How to Brew” by John Palmer. You can use the old version for free online or buy the new and updated one.
The first Brewing 101 post will be up in a a couple of days. The first in the series will cover the basics of brewing ingredients. I was going to try to cover the basic process also but it got a little long for that. Once the basics of ingredients and process I will start getting into more specifics by covering styles.
I will be at The Wheaty on Friday to try the new creatures beer. I will most likely be wearing a Toronado tshirt and black hoody so come up and say hi if you make it.
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