Homemade Wine Part 2 – Crushing

​Incase you missed part 1 of the Homemade wine edition series, we tackled quite a bit to do with sampling and harvesting of grapes in the vineyards and how the pro-winemakers gather their precious harvest. In addition, we also went ahead and reviewed certain grapes you can use to make your homemade wine. In part 2, we shall cover crushing and pre-fermentation of the grapes or fruits (for those making fruit wine).
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How its done…
Crushing the whole clusters of fresh ripe grapes is traditionally the next step in the wine making process. In some modern wineries, mechanical crushers are operated stomping or trodding the grapes into a wine must. In the old days (thousands of years), men and women from adjacent villages performed the deed in spectacular dances inside specialised old-fashioned barrels and pressed the grapes, mostly bare foot.

As with anything in life, change involves something lost and something gained. The mechanical process loses much of the romance and ritual attached to this highly anticipated stage of wine making, but also improves the quality and longevity of wine, while reducing the winemaker’s need for preservatives. Having said all this, it is important to note that not all wine begins life in a crusher. It is also important to remember that when preparing the red grape for the white juice, like in champagne or white wine, the juice is extracted by pressing and not crushing or stomping. The succulent grapes then release juice which is then fermented separately into white wine as we will see later. White wine is usually allowed very little skin contact (which impacts the colour of the wine).

As for red wines, they are fermented along with the skins and pressed afterwards. This allows the must to to garner color, flavor, and additional tannins. The musts are usually cloudy and settling is essential to allow separation of the suspended materials and in many areas wineries, a centrifuge is used to extricate the must to remove remaining solids. In some cases, red wine grapes are commonly de-stemmed and lightly crushed to allow the fermentation to take place with partially disintegrated grapes into the vat.
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What you could do…
So if you can remember the previous series, we identified some table grapes (in the absence of wine grapes) such as Delaware, Thomson seedless, Flame seedless, Kyoho, and Red Globe. We described these grapes in detail and now we will explore various DIY methods of crushing them into a pulp ready for fermentation.

​First, wash your hands thoroughly to kill unwanted germs that might contaminate the grapes. Carefully discard the stems and place the grapes in a clean sanitised bucket or container. With the intention of making the wine as intense as possible, rinse off any water in the bucket so that we are able to achieve possibly 90-100% grape/fruit juice extract.
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It is usually easier to stomp the grapes using your bare feet but if they can not fit in the bucket then use your hands to work on the grapes, leaving no grape uncrushed.

At this stage, you should see a wine must start to manifest characterised by a slimy cloudy liquid concoction with grape skins floating at the top. By the pro-book, must treatment is a ‘must’, which means that the crushed grapes are sometimes pasteurized, inactivating undesirable enzymes that cause browning. In some wineries (especially ones that mass produce) , additional chemicals may be added at this pre-fermentation phase to help preserve the richness of the natural enzymes that exist in the grapes.
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For our home factory, we shall deal with random bacteria developments a little different by adding a preserving agent called Sulfite (unless we want our wine turning into vinegar). You may be familiar with this chemical as it is often visible on wine bottle labels across the world. To get the correct sulphite calculus, our resources recommend the following quantities:


1 (regular) Campden tablet per gallon. that should be 0.440mg of metabisulfite for 3.8 liters = 0.220g of SO2. That would correspond to using 1.1g metabisulfite per 10L of must.


For slightly dirty/rotten grapes/fruits they recommend using:


60mg/l of SO2 so 1200mg per 10 liters. 1 gallon = 3.78 liters 10 liters = 2.6 gallons
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Properly incorporate the sulfite into the wine must and shake the mixture up until you are satisfied that is okay (you will know by looking at the bubble blend).
We shall now wait for approximately one day and then tackle the next step of the process which is fermentation.