Primary Fermentation
So now that you have put all that work into waiting, harvesting and (if you grew the plants yourself) even more work that I want to mention, it is now time to move onto primary fermentation. But, before we do let’s first discuss what we can do with our fruit to make it more prepared for this process.
*Note: Prior to using any equipment and I mean any, be sure to clean, sanitize and rinse anything the fruit/grapes may or may not come in contact with. You can use K-meta (Potasium Metabisulphite) as your sterilizing agent. Depending on the concentration of K-meta you purchase, mix 50ml (8 teaspoons), of K-meta to 4L (1gallon) of water. Double check directions on label if provided.
Grapes
If you are using grapes as your means of creating your wine you will need to firstly de-stem them. This can either be accomplished by hand (if you are making a small batch) or via a machine referred to as a ‘de-stemmer’. Neat eh? Well de-stemming can be quite tedious and if you have a big batch it may be worth your while (if you don’t own a de-stemmer) to look into renting one. Call up one of your local wine making stores and see if they either have one or know where you can rent one from. You may find one with a local wine making club.
Once the grapes are de-stemmed you will need to give them a good washing. While the grapes are growing out on the vines they are exposed to both particulate matter in the air and also to other foreign particles such as bird poop. Some grapes may even have been exposed to fungicides, herbicides and/or pesticides. These foreign substances (if allowed to progress to the next stages) can very easily infect and thus spoil you entire batch of wine. So make sure you take the time to wash the grapes properly and inspect them thoroughly for ‘little friends’
Next you will put the grapes through something called a ‘grape crusher’. A grape crusher will tear apart the grapes skins and begin the juicing stage.
Once all of the grapes have been run through the crusher it is now time to put them into the next machine which is called the ‘grape press’. This is a neat machine that slowly squeezes together the grapes skins and exacts any remaining juice. Be careful when pressing the wine. The higher the pressure in the press you use, the higher are your chances of breaking open the grapes seeds which will release unwanted stringency into your wine.
Note: If you are making a white wine you can proceed directly to the press (as you don't want the juice to have any contact with the grape skins (there are some exceptions to this rule). If you are making red wine then you want to give the juice as much exposure to the grape skins as you can. Red wine is fermented with the grape skins; white wine is not. Therefore if you are making Red wine you need to scroll down to the next part of this page where we discuss fermentation. Once fermentation is complete you can proceed to press.
Once the pressing is finished you have now successfully separated the juice out from the grape skins. Congratulations!
Other Fruits
The process used for other fruits is somewhat different then is the process used for grapes. There can even be variation from fruit type to fruit type for preparing the fruit for primary fermentation. The over all method stays the same – extract the juice from the fruit and either keep or discard the skins/pulp.
For simplicity purposes, the explanation for how Strawberries are prepared for strawberry wine is here given. Please note that there will be some variation by fruit type (especially hard fruits like apples and pears) and this method should not be used with all fruit wines. For more information regarding other fruit types please contact the cellar operator.
Once you have your strawberries, start by de-stemming them. This can be accomplished by using your fingers (provided they are well washed and sanitized, or are wearing rinsed latex gloves)
Once all of the strawberries have been de-stemmed you can now wash them for the same purposes are you would have washed the grapes. Once the strawberries have been washed place them into a plastic zip-lock freezer bag and then put them into the freezer until completely frozen through.
After the strawberries have been frozen, it is now time to thaw them and extract their juices. Take the frozen strawberries from the freezer and pour them from the bag into the primary fermentation bucket. Next boil water and pour the boiling water over top of the thawing strawberries. Use very little water here as you do not want to dilute the strawberry juice you are extracting. This will super thaw the berries which will aid in breaking the cellular membranes, letting the juices move freely from the berries. Leave in primary fermentor for one day to allow berries to completely thaw.
After 24 hours has passed, one of two methods can be employed to finish preparing the fruit for primary fermentation. You can either use your hands/arms (washed and sanitzed) and crush the berries in the primary fermentor, or, you can use the grape press. Which ever method you chose ensure everything was washed, sanitized and rinsed prior to use. And make sure anything that was used is rinsed and cleaned prior to storage.
Next, set up a large funnel in a straining pail, and cheesecloth bag in the large funnel so that you can sift the juice away from the pulp/skin. With enough pulp in the funnel, strain bag allowing dripping dry for 30 minutes. Tie the cheesecloth bag closed and place pulp bag into a retention bucket for now. Once all of the skins are prepared this way pour sifted juice back into the primary fermentor.
Note: This is a very specific way of juice extraction and I should say now that this method is not necessary for extraction. Once the fruit it cleaned it could go right to the press and extraction could occur this way.
Prepare the Must
You are now ready to prepare the must for primary fermentation. First thing is first. You need to create an environment in your must that will not allow any foreign yeast to spoil anything. For this purpose you need to add a small amount of potassium metabisulphate into your must. You want to end up with your must having 25ppm free S02. Try using the sulphite calculator to figure out how much potassium metabisulphite you will need.
If you are making a fruit wine you will likely need to add sugar to the must in order to bring your specific gravity up so that you will end up with the right amount of alcohol. Your must should start at around 1.08 SG – 1.085 SG. This will create a dry wine with about 10.5% alc. if you allow it to ferment completely. If you want a sweeter wine, it is suggested that you still ferment your wine dry and then back sweeten by adding more sugar, or concentrate at a later stage. You can measure your specific gravity with a hydrometer.
You will now need to make sure that the acid levels in your must are balanced properly. To do this you will need to understand the Basic Wine Acid Testing Procedure.
The remainder of the process for preparing the must is further explained within the recipe section of this website.
Adding the yeast
Once your must has been fully prepared you can add the yeast.
To determine what kind of yeast to use you can either refer to the recipe provided by the cellar operator or you can browse some of our suppliers' websites for a wide selection.
Make sure you give your must 12 hours of rest time between when the last ingredient went in to the time the yeast is added. As well, make sure the temperature is around 20-22 degrees Celsius at the beginning stages of fermentation. The yeast like it warm.
There are two ways of adding the yeast to the must. The first way is clean and simple however not always that effective. Simply tear the pouch of yeast open and sprinkle it on top of your must evenly. Some people will stir this in to the must however you do not need to.
The second way of adding the yeast to your must is to start a ‘yeast bomb’ as I like to call it. This is accomplished by filling up a sanitized measuring cup ¾ with your must and ¼ with water. Sprinkle you pouch of yeast into this mixture and wait approximately 30 minutes. This gives the yeast time to hydrate and even gets it started multiplying. After 30 minutes to an hour pour this ‘yeast bomb’ into your must. Even though this method is more time consuming and messy, it is more effective as your yeast population will have hydrated and begun to multiply. This will give your must a smoother and more efficient fermentation.
Cover your primary fermentor and let ferment. If you have skins in the must make sure to punch them down or stir them in at least once a day to prevent them drying out. There are several other additions to make during fermentation, however, these are explained in the recipes provided on this website.
Once the yeast begin to ferment the must and you can detect a strong presence of fermentation place the primary fermentation vessel somewhere colder - preferably 15-16 'C. This will cause a slower fermentation however it will help to maintain more aromas and structure in your wine.
This type of fermentation is referred to as anaerobic fermentation as it requires the presence of oxygen.
Once the specific gravity reaches approximately 1.02-1.01 you can rack your must into a carboy to complete the fermentation under bung/airlock. Ferment until complete (SG = .99, or .98). If you are making a red wine or a chardonnay, you are now ready to move onto secondary fermentation. If not, proceed to Stabilize, Degas and Clear/Finnings section.