
Hello all, today I'm going to do my best to give a basic step by step introduction into the world of cider making. This comes right off the back of a week away in Gloucester at the Cider and Perry academy run by Peter Mitchell. The course was an extremely in depth look at all the tiniest little details that go into producing the ciders that you all know and enjoy today. The course certainly taught me a lot and I was able to analyse our own cider in a much greater detail... no surprise that I now know how to improve our product and what changes I will make ready to make a new and improved product later this year so watch this space.
What I thought i'd do today is go through the process of cider making step by step from the perspective of someone in my position who is just starting out and looking to break into the commercial scene so here goes...
1) The first thing you're going to want to get hold of is obviously some fruit or some juice made from your desired fruit. For the sake of argument lets say you've opted to go down the route of pressing fruit. If you're growing your own apples you're going to need to decide what variety of apples you want to grow. This will come down to what kind of style cider you want to produce.
There are 3 kinds of apple, Culinary apples, Dessert apples and Cider apples all of which can be used to make cider. For example we currently grow just culinary apples. Within the Cider apple category there are then 4 sub types of cider apple:
Sharps - (high in acid, low in tannin) - acid content >4.5gl-1 and a tannin content of <2.0gl-1
Sweets - (low in acid and tannin) - acid content <4.5gl-1 and a tannin content of < 2.0gl-1
Bittersharps - (high in acid and tannin) - acid content >4.5gl-1 and a tannin content of >2.0gl-1
Bittersweets - (low in acid and high in tannin) <4.5gl-1 and a tannin content of >2.0gl-1
The balance of acidity to tannin and sweetness is something you really have to consider when it comes to making your completed product. Something I would bear in mind is that if you want to break into the commercial market, the preference is for a sweeter drink so at some stage you are going to have to consider the sugar but we'll get to that.
Tannins often add an astringent drying bitterness and body to your cider which is why you will want to balance that with some acidity perhaps from a sharp apple. Commonly Ciders are made from a balance of bittersweet and bittersharps, but as I mentioned the choice is completely up to you.
Now I'm not going to go into apple orcharding as that is a whole other topic all together. Let's say we've grown our apples and they are now ready for harvesting. It is vital to harvest apples at the correct stage of ripeness. If apples are unripe, the sugar content will be too low for fermentation and the flavour will not be fully developed. Use of over-ripe fruit that has been left on the orchard floor for too long, should also be avoided as off-flavours can be produced in the cider and apples will also start to rot due to contamination with the fungus (Phytophthora) which is ever present especially in the wet season just like phylloxera in vine growing. To know when your apples are ripe, cut them open, the seeds should be dark brown and taste them too, you'll be able to tell and underripe apple from a ripe one. You can also use the starch test: Immerse a cut apple in an iodine solution. If unripe, starch content will be evenly spread across the whole surface of the apple. As the apple matures and ripens the starch disappears from the central portion, leaving only a small amount on the periphery. Also whoever you bought the trees from, if they are a reputable supplier, should give you a rough timeframe of when that fruit will be ripe.
You can harvest your fruit either by hand or mechanically, or you've bought in your apples from someone else and had them harvested for you. Either way you are now at the same stage, the fruit is ready for milling. Now if you're just starting out like me then you probably don't want to go spending a load of money on all the swanky machinery and a decent mill will set you back a fair bit. My advice would be to get someone to do it for you. What we did last year and we will do again this year is hire a mobile milling and pressing service, if there isn't one of these in your area you can normally find a cider maker who will be willing to do it for you at a price of course.
2) Milling and pressing
Now once you've harvested your apples, if they are cider apples it might be desirable to store them for a couple of weeks, usually 2-4. Again this is a choice, with cider apples it can help to soften the harshness of the tannins. If however, you are going to be pressing dessert apples then don't bother with storage as these need to be pressed as soon as possible.
Before the apples can enter the mill, they need to be washed in order to remove stones, dirt and rotten fruit so that only the quality fruit is entering the mill an therefore the cider making process. From here on in it is all about quality control.
The idea of milling the apples is to aid with juice extraction. The apples are ground up to a pulp before entering the press. You may also wish to use enzyme treatment to help with the further breakdown of the apple and aid maceration.
The next step is to press the pulp to extract the juice. Now if you're doing this on a small scale, there are plenty of affordable press'. If you are on a slightly bigger scale however, starting out I would once again recommend getting someone else to do this for you. A rough target to aim for is an extraction of 650-850 litres of juice per tonne of apples. Juice yield depends on the fruit type and condition, the mash consistency, the temperature of the mash and the maximum pressure exerted by the press etc...
3) Preparation of the juice for fermentation:
There are 2 main aspects to consider at this stage, the potential alcohol production and PH control.
Potential alcohol production:
During fermentation, sugar is metabolised by the yeast to form roughly equal proportions of ethanol and Carbon dioxide. The measurement of Specific Gravity (e.g using a hydrometer or density meter) provides a reasonable value as to the amount of sugar present in your juice. Hence the potential alcohol concentration (%ABV) can be estimated as follows:
Estimate the likely drop in Gravity during fermentation. For the purpose of this, always presume the juice will stop fermenting at a specific gravity of 1.000 - e.g. If the initial SG is 1.050, then the likely drop in gravity will be 50 degrees.
%ABV = Gravity drop divided by 7.5 e.g 50/75 = 6.7% ABV
Alternatively you may wish to target a specific %ABV and calculate the amount of extra sugar to be added in order to achieve this. This is known as 'Chaptalisation' To do this follow these calculations:
Step 1: Calculate the overall required gravity drop during fermentation. For example, let's say we want to make a a drink of 8% ABV the required gravity drop would be 8%ABV x 7.5 = 60 degrees.
Step 2: Calculate the extra gravity required over and above what is already present in the juice: Extra gravity = required gravity minus that already present - 60 degrees minus 50 degrees = 10 degrees.
Step 3: Calculate the amount of sugar in grams required to raise the alcohol level. Amount of sugar (g) = fermentation volume in litres x required gravity x 2.6.
Let's say we're making 100 litres, the calculation would be: 100 x 10degrees x 2.6 = 2,600 (g) 2.6 kg sugar required to raise the %ABV to 8%.
PH control:
Before fermentation, the juice should be analysed for its acid concentration and then separately for its PH. Although acid concentration and PH are related, two separate data values should be collected. The measurement of acid concentration tells us the amount of acid present in the juice and the measurement of PH tells us the strength of the acid.
This is where you will be working in the Lab, you'll need a titration kit as the concentration of an acid can be measured by titration. This is when you mix the acid with an alkaline to produce a solution that is neutral, this is determined normally by colour change. PH will need to be measured via indicator strips or if you've got a boat load of cash... a PH meter.
The ideal PH level we are looking for prior to fermentation is somewhere between 3.3 and 3.6. If your PH levels do not fall between these values then adjustments will need to be made. The best way to achieve this is to blend together different varieties of fruit/juices with varying acid levels. Other ways of doing it include adding food grade malic acid in order to lower PH or adding calcium carbonate to increase the PH.
4) Sulfur dioxide treatment:
Sulfur dioxide is obviously a gas and so is a significant health and safety risk if added like this so it is usually added in the form of a solution of Sodium Metabisulphite or Potassium Metabisulphite. The advantages of using SO2 are that it kills off many spoilage organisms, it promotes a more efficient yeast fermentation, it can extend the shelf life of the cider as it has anti oxidant properties and it can help prevent in bottle 'chill hazes'. The amount of SO2 added prior to fermentation is dependent on the PH. If we are aiming for a PH of around 3.45 then the total SO2 required per litre is 100mg. Which if you're like me and not that good with numbers, keeps them relatively easy.
5) Fermentation:
Time for the main event. Essentially all fermentation involves is leaving the juice in a fermentation tank for around 2-4 weeks to allow the sugars to be converted into alcohol right? Wrong... unfortunately there is a little bit more too it than that. To start with we need to select a yeast strain that we think its going to best aid our fermentation and bring out desirable characteristics in our cider. Some cider makers use native yeasts found in their environment but others choose to buy in particular strains of yeast. In this article I'm going to talk about buying in the yeast as that is what I will be doing.
Your selection of yeast is so important as it influences so many factors. For example it will affect the temperature you ferment the juice at and will even go as far as affecting flavour of the finished product. Personally I'm going to be looking at using a strain of yeast known as Maurivin AWRI 1503, this yeast works particularly well with desert apples and can produce those fruity ester flavours that you may be wishing to impart on your cider. Now this yeast will typically like to work around 17 degrees celsius so bear that in mind, if you have your own tanks or are thinking of getting some, you may wish to think about getting ones with temperature control.
Now that we've chosen our yeast we can add it to the juice, which of course we are keeping in a food grade stainless steel fermentation tank. Yeasts will require nutrients for growth and vitality and therefore a successful fermentation. The big one to think about is a source of nitrogen. The way to manage this is if you start to smell a rotten egg smell then hydrogen sulphide is being produced, this is an indication of a lack of nitrogen, at this point simply add more nitrogen in the form of Free Amino Nitrogen or Ammonium. Yeasts will also need vitamins and minerals. The two main vitamins that can cause problems by their deficiency are Thiamine (B1) and Pantothenate (B5) about 0.5gl-1 and 0.25gl-1 respectively are needed either in a prior yeast solution or directly added. Oxygen is also needed so you will need pumps to pump in O2 and thoroughly aerate the juice.
So the fermentation period will last roughly 2-4 weeks, this can be cut shorter or extended drastically and is completely up to you as the cider maker. Fermentation typically ends when all the sugars have been metabolised and a 'dryness' is achieved in the cider. The Specific Gravity will fall to 1.000 or sometimes just below this. Yeast and other solid material will have gathered at the bottom of the tank to form the 'lees'. This leads us on to the next process known as racking.
6) Racking:
Racking should usually be done as soon as possible after fermentation has finished in order to minimise the effects of yeast autolysis. The basic principle of racking is to separate the cider from the leftover yeast and other solids (lees). To do this you will need to pump the cider out from a point above the lees formation. The main objectives are to minimise waste and maximise cider recovery and avoid aeration as much as possible. A lot of people forget at this point that there is a lot of CO2 that has been produced as obviously its a by product of fermentation. Whatever you do, don't go sticking your head in the tank and risk carbon dioxide poisoning!
After the Cider has been racked, you have a few options to consider. You may wish to re-sulphite as well as checking the PH levels again to see if they need adjusting. At this stage, depending on what kind of product you want to make, you may wish to filter the cider. You will also want to re-assess the cider for alcohol concentration to check it is in line with the %ABV that you were aiming for.
7) Maturation:
Raw fermented cider will benefit significantly from a period of maturation. The cider will improve in flavour, developing more complex notes. Also with cider made from cider apples, if the juice is particularly high in tannin then a period of maturation will help to soften the harshness of the tannins, creating a softer more pleasurable drink.
Managing the maturation period is very important, it is vital that the cider has no air contact as not to oxidise the cider and produce off flavours. For this I would recommend using 'Bag-in-box' storage systems.
Realistically you can leave your cider to mature for almost as long as you like, typically anywhere between 1-8 months. All you need to be doing is keeping an eye on the flavour profile and stopping the maturation process when you are happy.
8) The down streaming process:
This stage is where your cider becomes a cider that people will want to drink and evolves into a finished product. To start with you may wish to put the cider through fining. Fining is the addition of a reactive substance that will remove any unwanted components, e.g; cloudy particles. The two main fining agents on the market are Bentonite and Gelatine. The agent will require mixing thoroughly with water and sometimes malic acid (for bentonite) before it is added to the cider. You should always run fining trials before doing it for real in order to determine the appropriate dose. Once you have established the dose, the suspension of water/malic acid and agent must be added slowly and mixed in well. The liquid must be allowed to stand undisturbed and the temperature must be kept constant.
Now we get to the last and arguably most important steps of our cider production - the BLENDING.
On its own a straight fermented 'dry base cider' is quite a challenging drink and the majority of consumers don't like it. The base cider therefore, normally requires blending with other ingredients, such as sugar. There are two main options for obtaining a sweetened cider: Arrested fermentation and Back sweetening. Im going to talk about back sweetening as this is in my eyes an easier process and will be the one that I will be using. Back sweetening involves the addition of sugar (fructose and sucrose are commonly used), fresh apple juice or apple juice concentrate after the base cider has finished its maturation period.
The blending process can also involve the mixing of different 'base' ciders and really any other ingredient you may wish to add in order to achieve the flavour you are looking for. This part is completely up to you as the cider maker and you will need to do many tests and tastings until you are happy.
As a rough guideline:
If you're aiming to make a dry cider: The specific gravity will be around 1.005 with up to 13g sugar/litre.
A medium cider: SG of around 1.010 - 1.015 and 26-40g sugar/litre.
A sweet cider: SG of around 1.020 and 50g sugar/litre.
If you wish to make a sparkling product, the cider will need to now undergo carbonation. Put simply this involves subjecting the cider to pressurised CO2. The product will need to be chilled as it allows for a lower gas pressure needed to carbonate the product. My advice would be get someone who has decent machinery to do this process for you as well as bottling.
And that wraps up a basic guide to making cider. Hopefully i've given you the foundations to go off and do some more research and start making cider for yourself. If you are planning on making a cider, best of luck, send in some photos of it finished and watch this space for our new cider later this year.
Until next time, cheers.