The juice ferments with grape skins to turn it red, which is a keyway that red winemaking differs from white winemaking.
Red wine production involves more than just the colour, of course. Your palate will improve from learning the quality and taste secrets revealed by the process. So let's go over each step red wine goes through to get from grape to glass.
What is Red Wine
Before we delve deeper into the process, let’s define what precisely red wine is first. Let’s begin with the fundamentals; red wine is an alcoholic drink created by fermenting the juice of grapes with black skin.
White wine and red wine are produced using different raw materials and techniques. Dark-skinned grapes, instead of light-skinned grapes, are used to make red wine. To create red wine, the winemaker allows the pressed grape juice, referred to as "must", to macerate and ferment with the dark grape skins.
This process gives the wine its colour, flavour, and tannin. When yeast breaks down grape sugar into ethanol and carbon dioxide, alcohol is produced. Red wine is the end product of these procedures.
Characteristics of Red Wine
Red wine's colour is its first and most evident characteristic. The colour of red wine can range from opaque to dark purple, light ruby, and everything in between. Red wine's vibrant, young colours fade to garnet and even brown as it ages.
Tannin is the second attribute of red wine. Red wines are produced through whole cluster fermentation, which involves macerating the juice of the grapes with the skins, seeds, and occasionally the stems. These grape bunch components all give the wine tannins.
Tannins, and polyphenols, give a wine texture, structure, and age-ability. They are the cause of the black tea-like drying sensation in the mouth. While certain tannins may be viewed as rustic, green, or astringent, others may be deemed ripe, smooth, or well-integrated into the wine.
Tannins give the wine a skeleton-like structure or framework. Many believe that young, tannic wines are best savoured after a few years of maturing in the bottle because they soften over time.
Red wine's broad flavour spectrum is its third unique characteristic. Different grape types emit scents reminiscent of various fruits, flowers, herbs, spices, and earthy elements. In contrast to Cabernet Sauvignon, which typically has cassis, liquorice, and wet gravel notes, Pinot Noir typically has raspberry, cherry, and forest floor.
These flavours and fragrances aren't added to the wine; they make up its unique organoleptic qualities, which are made of organic components usually found in grape skins and acids. Due to the variety of grapes used and the contact with the skins during maceration and fermentation, red wine has different qualities than white wine.
Acid is the fourth quality of red wine. Wine must contain acid because it preserves the wine and gives it freshness and structure. When tasting red wine, the tart and sour flavours that balance the sweet, bitter, or tannin components are called acidity. Although tartaric and malic are the two primary acids in red wine, there are also other types.
Step by Step Process of Making Red Wine Grapes (Winemaking)
Depending on the targeted wine style, the precise winemaking procedure varies, but for the most part, winemakers follow these basic procedures:
Purple or black wine grapes are used to make red wine. Anthocyanin, a crimson pigment found in black grape skins, is, in fact, the source of all the colour you see in a glass of red wine.
The most crucial (and stressful) time of the year for all winemakers is during the grape harvest. Picking the grapes at the ideal stage of maturity is the most vital step in the grape harvest. It's essential because grapes stop ripening once they've been picked.
- Wines made from too-early-picked grapes may taste thin and acidic.
- Wines made from grapes gathered too late may taste too ripe and flabby.
2. Crushing The Grapes and Destemming
The berries are separated from the stems and lightly popped to release the juice, which is rich and aromatic. At this point, you will often add potassium metabisulfite, which has a sulfite content of about 50 ppm (SO2). This will destroy any rotting yeasts and undesired microbes, but it won't affect the more resilient wild strains of Saccharomyces cerevisiae (wine yeast).
To reduce the risk of oxidation, it is crucial to crush and destem the fruit as soon as possible. If you're feeling energised, you can overcome and destem using your hands or feet and the motorised crusher de-stemmer. If working with small batches, you could smash and destem the fruit using a clean milk box.
You should decide if you want to ferment a portion of complete clusters or whole berries during the crush and destem phase. Utilising entire collections prolongs the fermentation process and boosts fruity smells by delaying juice release from these berries. In wines like Merlot, Pinot Noir, and other fruit-rich wines, 20–25% of entire clusters are typical.
Another comparable method includes separating the berries from the stems without exploding them, and it is called whole berry fermentation. However, since berries easily break as they are separated from the branches, this is exceedingly challenging to accomplish at home. For entire berry fermentation, delicate, specialized de-stemmers are employed to remove the stems.
3. Cold Soaking (Oak)
Red wines frequently undergo extended maceration, extending the time the juice and skin have in touch before or after fermentation. Increased skin contact duration might enhance flavour and colour extraction. While more alcohol-soluble components, like tannin, can be extracted by soaking after fermentation, soaking before fermentation aids in the extraction of water-soluble components like fruity esters.
The more popular method of extended maceration is known as "cold soaking," which entails freezing newly crushed and destemmed must to an optimal temperature of 35 to 45 degrees Fahrenheit for a few days before starting the fermentation. Yeasts and spoilage germs can't survive in this kind of temperature. Because the spoilage yeast kloeckera (fungus) thrives in this temperature range over wine yeast strains, do not let the wine sit in the 50-55°F range.
To enhance extraction during the cold soak, consider fermentation enzymes like lallzyme EX. You can also consider adding untoasted wood cubes or fermentation tannins to help retain anthocyanins, which are responsible for the wine's colour and structure. Wines from colder growing locations may have less vegetal (bell pepper) smells because of the usage of untoasted wood and fermentation tannin.
4. Obtaining A Second Measurement (Winemaking)
Take measurements of the sugar and acid near the end of the cold soak. This is an excellent opportunity to get a more precise reading. If measurements are low, you can add tartaric acid or table sugar; if they are excessive, you can add water (gasp!). Although it is rarely discussed publicly, extensive vineyards can modify the most upfront with vacuum distillation and reverse osmosis.
5. Starting Fermentation
If you finished cold soaking, warm the wine as soon as possible until it reaches a temperature of around 70 or 75°F. The "good guys", saccharomyces cerevisiae, flourish in this range and typically overpower the other yeasts and bacteria that might wish to feed on your carbohydrates. Here, you can add cultivated yeast or carry out a natural fermentation.
You can choose, but adding a cultivated strain is significantly less dangerous. One approach is to pick off a gallon of must before cold soaking and let a natural fermentation begin on the sample if you want to live dangerously and perform a wild fermentation. After a brief cold soak, combine that batch with the larger one if everything appears in good health. You should inoculate with cultured yeast if the sample doesn't seem to grow or smells pleasant.
Select a strain of cultured yeast suggested for your variety and the fermentation temperatures if you're inoculating with it. Some strains, like the aggressive Lalvin EC-1118, provide a clean fermentation but may also hinder extraction because quick fermenters drastically shorten the skin contact duration.
I prefer Lalvin RC212 because it is dependable but somewhat slow, which is appropriate for red wine. Lalvin was isolated from the Burgundy wine area of France. Make sure you have some Fermaid K or fermax available because this yeast wants to be fed.
6. Punching and Monitoring the Wine
As fermentation begins, the grapes will fill with CO2 and float above the liquid. It's crucial to submerge these to avoid drying out and oxidation while also allowing the fermentation that is already underway below to breathe and circulate. This churning/submerging maintains the yeast's health and happiness since it will absorb some air during active fermentation.
Push down the cap two or three times per day using a handmade or store-bought punch-down tool. Keep the seeds intact while pushing the skins to the bottom of the tank. Be sure to agitate any foul lees that may have accumulated at the bottom. You can perform a pump-over rather than a punch-down if you work with huge volumes. This is the procedure when the wine is pumped up onto the must at the top of the tank.
While the fermentation is active, keep a constant eye on your temperature. To extract any fruitier, water-soluble flavours, let the mixture warm up a little (80–85°F) for the first few days. Later, I let it cool down (70–75°F) to extend the skin contact duration. For smaller quantities or dry ice for bigger ones, you can use frozen water bottles to cool it down. When necessary, replace the water bottles, and before submerging them, make sure to clean them by spraying them with Starsan or homemade sanitiser.
Feed your yeast and ensure your temperature is within a range that your yeast is compatible with if you detect even the slightest whiff of rotten egg odour. Never feed your yeast all at once, and stop feeding it once the sugars have reached about 10° brix. After fermentation is finished, any nutrients left behind from the yeast can be eaten by unwelcome bacteria.
7. Pressing The Wine
By this point, your wine has started to take on the taste of wine by this point—a hot, powerful, overpowering version of fine wine. To eliminate the possibility of stopping the fermentation, it's better to press the wine until after it has completely dried. Fermentation typically lasts between seven days and three weeks.
If you want to be highly concerned about oxygen, you can still press with a small amount of sugar. But it's not a bad thing to get some oxygen right now. It will catalyse to change of short-chain tannins, which are abrasive, into long-chain tannins, which are smooth, and it will aid in binding your vibrant anthocyanins so they remain for a long time.
You should keep hard-press wine and any free-run wine apart during pressing. Free-run wine escapes from the press prior to pressing and is frequently seen as more expensive. After maturing is complete and the wine expresses itself as it wants, you can choose how much hard press you want to mix back in.
Press into a short-term container such as a stainless variable volume fermenter, a carboy, or an argon-filled food-grade barrel. The gross lees will settle to the vessel's bottom in roughly 24 hours. So go ahead and rack your wine off these once they settle because the foul lees will begin to smell if left to consolidate on the bottom of the bottle.
A modest number of fine lees is acceptable and can aid in feeding malolactic bacteria, which is often advantageous. When racking off the gross lees, you can transfer the wine directly into an airtight stainless-steel tank, a carboy, or a clean oak barrel. You do not need to add sulfites by this point if malolactic fermentation is what you intend to accomplish.
8. Performing Malolactic Fermentation (MLF)
This process turns the tart, apple-like malic acid into smooth, buttery lactic acid. Adding a freeze-dried malolactic culture seals the deal, even if a wine frequently goes through MLF naturally without much support from you. Add the culture directly to the barrel or other ageing container. Tiny CO2 bubbles will appear in a wine that has undergone MLF. Depending on the culture employed, the wine's pH, and the temperature, MLF will finish in one to several months.
In contrast to a quick, efficient MLF, a prolonged MLF will produce more buttery flavours while minimising the buttery characteristics. You must choose your course of action in this situation. The primary methods for accelerating it are a slight rise in temperature, feeding the bacteria, or utilising a more aggressive bacteria culture. To induce a slow MLF, do the exact opposite.
If you want to completely prevent MLF (perhaps because your pH is already too high), add a lot of SO2 (100 ppm), store the wine at or below 60°F, and consider including lysozyme. Filtering is recommended if you do not intend to let the wine undergo a complete malolactic fermentation.
9. Ageing the Red Wine Grapes
You should rack the wine off the fine lees and add sulfites to preserve it for a long time once you are sure that MLF is finished. You can use a chart to determine the fitting addition for your pH level.
However, adding more now and less afterwards (still maintaining a low total SO2 addition number) is okay. You should only need to add a little more later on if you are merely guessing at your SO2 concentration because you cannot monitor it. Aim for 60 to 75 ppm now. Tannin also serves as a wine's anti-oxidant, so if you prefer to err caution with SO2, you should add some ageing tannins (especially if you are not soaking the wine).
About once a month, you will need to top off your wine supply if you are ageing in an oak barrel. Depending on your humidity level, a 59-gallon barrel will require between one and four bottles of wine to be added each month. Try putting your barrel somewhere with enough humidity, like a cellar, as dry air will speed up the evaporation.
Micro-oxidation, a process that takes place in barrels, also aids in reducing the tannin in wine. Micro oxidation is very difficult to reproduce in stainless steel or glass containers. Avoid overlooking the wine by storing it for an excessively long time in a fresh oak barrel.
Consider oak alternatives like chips, cubes, spirals, or staves if you are ageing in stainless steel or glass. These come in various toast styles, including French, Hungarian, and American.
Ensure that the wine can occasionally cool to a temperature of less than 50°F for a few weeks. This will encourage unstable tartrates to disperse in the storage container rather than the bottle. Crystals will not harm the wine in the bottle but may distract the drinker.
10. Blending and Bottling
Your wine will be ready to be bottled after several months of ageing. Consider mixing the wine to perfection before committing to bottling. Even if it is designated as a single varietal, almost all commercial wines have undergone some little blending
It's time to apply the mix to the entire batch and bottle if you have a few different wines on hand and have discovered the ideal blend. One thing to remember is to always combine and taste at the right serving temperature. The sense of a wine's balance, intensity, and texture can be greatly impacted by temperature.
Simply check your sulfite levels, add more if necessary, and then bottling and corking the wine is all that is required to bottle the wine. Ensure that your bottles and bottling tools are sterile and clean before you start, and then go for it! Before serving, allow the wine to rest for at least four weeks after it has been bottled. A brief bottle shock that develops due to the oxygen added during bottling should disappear within a few weeks.
11. Your Wines is Ready to Be Served!
Take a sip of your wine and share it with your friends. Each time you open a new bottle, make an effort to examine it. To keep your taste buds in check and understand your competitors, it's crucial to compare your wine to other similarly priced commercial wines.
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