The practice of wine, good wine requires a complex process of.
(i) Grape Pressing.
1. Prepare fermentation containers: If possible, use stainless steel jars or glass containers, such as small-mouth bottles. Food-grade plastic containers are really unacceptable. Some winemaking friends use jars, which is not a good method because wine is acidic and can easily cause trace chemical reactions that can make wine strange.
2. Clean the container. If possible, you can clean it once with high strength white wine (52%), then 3~4 times with tap water. Finally, wash with distilled water. Generally, grapes do not need additional washing because farmers stop using all insecticides more than a month before the grapes ripen, which would make the effect of the drug expire.
Apart from rainwater washing, the grapes do not contain toxic or harmful substances except for some dust. Of course, this is only for professional wine grapes. If you are using fresh grapes, such as the variety of Giant Peak and Rosemary, it is recommended to wash the grapes and dry them.
3. Destem and crush the grapes. It is best to pick the whole grape, remove the stems, crush the grapes and put it in a clean container, two-thirds of the container, up to 80%. This prevents the fermentation volume from getting bigger and rushing out of the container. If you are able to make wine, you can add early tannins at this time, which will improve the structure of the wine and enhance its ability to age.
(ii) Fermentation.
1. If possible, brewers can add potassium bisulfite. Start by adding 2-3 grams of potassium sulfite. After 4 hours, add 30-50 ppm of pectin enzyme, which clarifies the must, extracts pigments and flavorings, and increases the juice yield. If you don’t have this condition, you can skip these two processes and use the natural yeast on the surface of the grapes for fermentation.
2. Add yeast 12-24 hours after adding SO2, adding about 20g 100kg of grapes (yeast needs to be activated). How to activate yeast: Add active dry yeast to grape juice or aqueous solution containing 5% sugar at 32-38℃, stir well and leave to activate. After 20-30 minutes, the yeast will be revived and added directly to the grape juice.
3、When the grape juice has bubbles, turbidity and grape skin on the top, stirring means fermentation has started. Do not seal it at this time, otherwise there is a risk of explosion. Stir once every 6 hours, three times a day. The fermentation will be even, the skins will be decolored and the nutrients will enter the wine. The best fermentation temperature is 24-28°C.
At the same time, add sugar according to the measured sugar content of the grape juice (you can check the table on Baidu for the alcohol content corresponding to the original sugar content). Adding method: Dissolve the required sugar in some grape juice first, then add it to the fermentation tank to distribute the sugar evenly in the fermentation juice. Generally speaking, 18g/l of sugar can increase the alcohol content
(iii) Separation and aging of stripped residues.
Put the original wine fermented for about 7-10 days into another container with peeling residue: the juice sieve can be medical gauze or nylon gauze (less than 100 mesh). Experienced people pour the clear juice first, then the leather residue. Then squeeze the leather residue to squeeze out as much juice as possible. Pour them into the coarse wine. Of course, there is a better professional device: a juicer.
Juicing with a juicer can increase the juice yield by about 15%, making it much more efficient. Full capacity sealing of the container: Fill the container with the original wine and connect the bottle mouth with a one-way valve or an exhaust valve (so that the gas produced by the secondary fermentation is discharged from the bottle and no external gas can enter).
If the seal fails, pressure can easily cause the cork to arch, bringing the wine into contact with air and causing oxidation and spoilage. The next step is: secondary fermentation (also known as malolactic fermentation, or MLF), which converts the malic acid in the wine into lactic acid and carbon dioxide, thereby reducing acidity, mellowing the flavor, and improving bacterial stability.
It is not mandatory that natural secondary fermentation is possible. If possible, try to keep the temperature at 18-20°C and ferment in a cool place away from light for about one month.
(d) Pouring the tank to remove the sludge.
1. Replace the original wine from the second fermentation into another bottle: generally do not use the pouring method, as it is easy to pour out the wine sludge and make the wine turbid. You can use a silicone tube and a wine suction device to guide the wine. The clear juice is put into another bottle and sealed.
2. Those who are qualified to make wine can follow the same procedure as before: add potassium bisulfite pellets and add 4-6 grams of 25 liters of wine to keep the wine quality stable. At this point, oak chips can be added to improve the overall taste of the wine and add complexity.
The amount of oak chips to be added varies depending on the grape variety. American oak chips are recommended for fruity wines with stronger vanilla flavors and more immediate aromas, making them more suitable for New World enthusiasts.
For aged wines, such as high-end Cabernet Sauvignon and Merlot, consider French oak chips, which can bring more cedar and smoky flavors to the wine, but there are no specific rules on the type of addition, and it is entirely a personal choice.
The theoretical dosage is 1g/l. Of course, winemakers can add a little less and then taste it after a month. If the oak is not enough, they can add it again for more flexibility. Then it will be completely sealed for about a month.
(v) Clarification.
The wine is poured again to remove the sludge. Then add a certain amount of clarifying agent. It is recommended to add gelatin to red wine because of its soft texture. It is recommended that bentonite be added to white and fruit wines, as it makes little difference. It precipitates suspended matter and polymeric proteins in wine, making the wine clear and transparent. Do not add too much, otherwise you will lose a lot of color and flavor substances.
You can also make your own clarifier from egg whites, with the same effect as before: the method is to add one egg white to 20 pounds of wine, beat the egg white into a foam, add it to the wine, stir it well and let it settle for about ten days.
(vi) Bottle filling.
1. The clarification effect can usually be tested in this way: point the candle to the other side of the bottle and then look at the flame of the candle from the other side of the bottle. If the flame outline is clear, the clarity is good and the bottle can be filled. If the flame is blurred or you can’t see it at all, the result is poor and you can continue to place it.
Another way is to put your hand over the bottle and use five fingers, or even your fingerprints, which is ideal. Otherwise, the effect is not good. Continue to place. If you can place it outside at -10 degrees, you can leave it in this environment for a week. First, it will enhance the clarifying effect. Secondly, it will reduce the amount of tartaric acid and make the wine smoother.
2. Filling: There are now some home wine filters on the market. If you have the means, you can choose one. Filter the wine by CO2 pressure or gravitational potential siphoning and bottle it at the same time. You can also pour the clarified wine directly into the bottle. The former is more stable and refreshing. The sensory clarity is also clear and very pleasant to look at. It’s a pleasure to drink!
3. Cork the bottle, heat shrink it, attach the wine label, and enter the bottle. If you make the wine in September, it will be around April and May of next year. Six months of bottle aging is best.
