So you’ve heard the term All Grain brewing on forums and in brewing circles but what’s it all about?

Lets give you an overview of this mysterious art and show you it’s not as complicated as it may appear. One of the first confusing issues is the strange terminology. Mash, Sparge, Grist, Liquor – these terms come up often in brewing literature and are off putting but they are simply alternative words used by brewers to describe fairly simple procedures. As we go through the process these will demystify!

Considered the holy grail of home brewing, All grain brewing is certainly the most advanced method as it relying on skill and knowledge to create the beer completely from raw ingredients.

 

You are basically making your own malt extract from malted barley. Once that is complete the rest of the process is similar to that of extract brewing. Boil, cool, Ferment. All grain takes longer so you so allow 6 – 8 hours start to finish. This most advanced method of brewing and the method used by professional brewers. Get it right and the results cannot be beaten!

The full mash method consists of these main processes.

Mash

Sparge

Boil

Cool

Ferment

The Mash:

Malted barley is mixed with hot water and left for a period of time.  Its as simple as that. The hot water dissolves the starches and activates the enzymes in the malt producing fermentable sugars. This is then known as sweet wort. Unfermented beer before hops have been added.

The ratio of water/grain can vary but its generally accepted to use 2.5L of water / kg of malt.

Temperature is important and will determine how fermentable the sugars will be . Higher the temperatures create sugars that are more complex and therefore less likely to be fermented by the yeast. This will leave residual sweetness and body in the beer. Lower temperatures create simpler sugars which are more easily fermented. This will give a beer higher in alcohol with a drier finish.

The ideal temperature range is somewhere between 63c to 68c (150 to 155 f). Wort produced outside this range will result in too many unfermentable sugars or low starch conversion. The majority of home brewers aim for a 65c. This produces a good balance. To reach the desired final mash temperature the water needs to be hotter as the cool grains will lower the temperature. This is known as the strike temperature. Other factors like ambient environment and temperature of equipment will also have an effect. Once mixed, the temperature can be adjusted simply by adding hot or cold water.

Once you have used your equipment a few times you will get a feel for what temperature the mash water needs to hit the correct temperature. The mash is then left for the magic to take place and this usually takes happens in around 60 – 90 minutes. Iodine can be used to see if any starch is still present. Just take a liquid sample from the mash, add a few drops of iodine and if any blue is present then leave the mash for a while longer. Most home brewers use an insulated mash tun to hold the mash at the desired temperature.

The mash process can be broken down into the following:

1 – Prepare and heat water

First step is to get the water for the mash to the correct temp. Bear in mind that this can take some time depending on the type of boiler used. Many brewers use a separate hot liquor tank (HLT) which is rigged up to a timer. They then prepare the water the night before, set the timer and the water is at the correct temp when they get up. This can reduce brew day times by a hour or more.

2 – Check and weigh ingredients

To ensure a stress free brew day, weigh out all the ingredients in advance and label all hop additions with the time they need to go into the boiler. These grains as referred to as the grist.

Dough in

1 – Add grain/water to mash tun

Adding the grain to the mash tun and mixing with water is known as doughing in. The best way to do it is to add the water to the mash tun from your boiler, or HTL via the tap and add grains bit by bit as enough water has been transferred. This will ensure minimum lumps and dry areas. Do not over stir the mash as you will cause a stuck mash. Use a spoon and just slice though the grain with a careful side to side motion to ensure there is no lumps. A stuck mash is where the run off from the mash tun gets blocked and therefore you are not able to empty the liquid into the boiler. Its rare but if it does happen it can be fixed. Simply stir the grain and leave to settle for a bit. This should sort the blockage.

2 – Leave to mash and heat sparge water

Put the lid on the mash tun and leave for the mash to complete. This should only take an hour but no harm will be done if you leave it for many hours longer which can be handy if you have some other things to do in the middle of a brewday. Remember to bring the sparge water around 77c in advance as it may take a while to heat.

Sparge

The next stage is to sparge the mash. The word sparge originates from the Latin term “spargere” meaning to sprinkle. This process simply rinses out all the sugars produced in the mash into the boiler. Again the temperature of the sparge water is important. Aim for between 74c – 77c (165f – 170f). Too hot and tannins from the grains will be dissolved and carried into the wort resulting in harsh, astringent flavours. Too cool and the run off will be less fluid causing less extraction of sugars.

There are several methods of performing the sparge by home brewers but the most common are continuous (fly) and batch.

Continuous sparging involves a thin sprinkle of water being added to the top of the grain while the mash tun is being run off into the boiler. Water will always find the easiest exit route so a thin spray ensures that no channels are created between the sparge spray and the exit point. The sparge water will then run through as much grain as possible dissolving and extracting as many sugars as it goes. The flow out should keep up with the flow in.  The grain bed should neither get too flooded or too dry. This should be a fairly slow process and taking around 40 mins for a 5 gallon batch. You can use a rotating sparge arm for this. The arm has several holes in it and rotates by the force of the water. This delivers a fine spray to the top of the grain. The small recirculation is advised at the start of sparging. Draw a couple of jug fulls of wort from the mash tun and return to the top of the mash. This will allow the grain bed to settle down which will then act as filter as the liquid run’s through it.

Batch sparge is another popular method with home brewers. This is perhaps the easiest method and requires less equipment. Hot water is added to the mash in two or three batches, stirred and left to infuse for 20 mins. Runnings are then taken from the mash tun and returned to the top of the mash, as in the previous method, to allow the grain bed to settle down the rest of the liquid is then emptied into the boiler. More hot water is then added and the process is repeated. This method is less efficient than continuous sparging and may require more grain in the mash to achieve the same starting gravity.

How much water is required for sparging will depend on your equipment and method of sparging but around 20 litres should be sufficient for 23 litre batches. Sparge until your boiler is to the required volume or the gravity falls below 1.010.

Boil

Once the sparge is complete then its time to get the boil underway. Bring the wort up to the boil and wait for the thick head which will form to break. This is known as the hot break and is caused by proteins from the grains sticking together like the white of an egg when cooked. These proteins will then sink to the bottom and eventually be filtered out by the hop bed ensuring they are not transferred to the fermenter. This is known as trub and although not devastating for the fermentation it can cause some issues for the yeast. Once the hot break has occurred then the hops can be added as per the recipe schedule. Remember to also add Protofloc or irish moss in the last 15 mins. These finnings will help attract any particles in the wort and make them clump together making them easier to filter. It’s important to boil as with the lid off.  DMS, a compound found will give undesirable flavours in the final beer. Luckily its highly volatile so will be easily boiled off but if you have the lid on with collect and go back into the wort. You will need a large boiler which is capable of boiling the full volume of the brew, which for a 23L batch will be around 26L.

Cooling

Once the boil is complete and any aroma hops have been left to infuse then the wort needs to be cooled as quickly as possible. There are two main ways for the home brewer to achieve this. The best way is by using an immersion chiller . This will cool the wort to yeast pitching temperature in around 20 minutes. If you don’t have a chiller then placing the boiler in a bath of cold water will achieve the same results but will take longer. If using an immersion chiller, sterilise it by placing in the boiler for the final 10 minutes. This boiling action will kill any unwanted bacteria and eliminate the need for any chemicals.

Quick cooling has the added benefit of creating a cold break. Proteins from the malt stick together and therefore are not carried over to the fermenter. If these proteins remain they can cause chill haze as they stick together when the finished beer is chilled. Although this is a purely cosmetic problem and will not effect the taste its best avoided. Once the wort is cooled to around 20c then transfer to the fermenter

Place the boiler on a higher surface and open the tap full so the wort flows out and drops into the fermenter. The splashing action will introduce oxygen to the wort enabling a healthy start to fermentation. Its also a good idea to then oxygenate the wort by vigorous stirring for 10 minutes. This gives yeast plenty of oxygen enabling them multiply and produces a healthy fermentation.

Once the yeast is pitched the process is exactly the same as any other method. Just ferment until complete then transfer to bottles or kegs for storage and serving.

Hopefully this has been given you a taste of all grain brewing. We will cover the subject in more depth in forthcoming posts but if you have any questions please feel free to ask us via email or on our live chat facility.

If you have want to have a try with basic equipment check out our great stove toppers range.