Winemaking is a process that combines both science and ancient taste to produce an alcohol-rich beverage. Grapes are ideal for making wine because of their acidity, sugar and tannin levels.
Harvesting can be done by hand or by machine. However, many estates prefer to hand-harvest as mechanical harvesters can be tough on the grapes and vineyard.
Fermentation
Fermentation is an ancient technique that can still be found in many modern foods, including bread, wine, cheese, sauerkraut, and yogurt. In these fermented foods, yeast and bacteria convert sugars into alcohol or acids, which help to preserve them.
Yeast is a key part of the winemaking process because it metabolizes grape juice sugar into alcohol. Yeasts come in all shapes and sizes, from wild yeasts that live on the fruit and are unpredictable to cultured yeasts that have been specially engineered for the purpose of making wine.
Yeasts are fed with a mixture of vitamins (yeast nutrients), which supply them with their energy source as they ferment. They also need sugar to survive and thrive. Temperature is another important factor in the fermentation process because it affects how much alcohol and flavour can be extracted. Warmer fermentations tend to be more effective for fresher, lighter styles of wine, while cooler fermentations are better for heavier, more complex wines.
Bottling
Winemaking is an intricate process that can take years of experience to perfect. It involves the selection of high quality grapes, fermenting the liquid, and aging it to develop its flavors and aromas.
The resulting wine may then be bottled and sold. The bottles can vary in shape and size depending on the region, but the sturdiness of the bottles plays a big role in how long the wine will last.
Bottling can be a tricky process as it must ensure the wine doesn’t become oxidized, which could spoil the flavor and aroma. Most bottles are capped with corks, which help to prevent oxygen from entering the bottle and causing the wine to spoil.
In addition, a special procedure called riddling or remuage is usually done to move yeast debris from the bottom of the bottle down onto the cork. This is done daily, usually for several weeks or months. The remuage helps to create the smooth, round character that many people associate with a good wine.
Ageing
Ageing is a process that takes place during storage of wine and it is very important to the final quality of the product. During aging, a series of reactions take place that change the chemical composition and organoleptic properties of the product. These changes result in modifications to the tertiary aroma and complexity of the flavor and its astringency [3].
Aging is carried out in barrels or bottles. During oxidative aging, wine is exposed to oxygen and a series of cellular processes take place that alter its physical and chemical properties.
Oxidation of the wine is influenced by different factors, such as the pH, temperature, concentration of dissolved oxygen and the phenolic composition of the grapes. The oxidation process is mainly responsible for a decrease in the color, the loss of varietal character and the development of aldehydic aromas.
The oxidative aging process is very important in wine, as it is a way of improving its final quality. However, it can be difficult to achieve this, as many factors can influence the aging process, including the type of wood used, the amount of time it is in the barrel and the microbial growth.
Storage
Winemaking involves the careful management of vineyards to ensure the production of grapes with optimum flavor. This is followed by controlled alcoholic fermentation and possible barrel aging.
Wines are then placed into bottles for storage or distribution to the market. This process is thought to improve wine properties such as a lower astringency, a softer mouthfeel, and an improved aroma.
However, this process can be complicated due to the different chemical changes occurring within the bottle. Temperature control and reduced light exposure are two key factors that affect the storage of wine.
Wine is sensitive to temperature change and should never be stored too hot, as this can cause it to spoil. A good range for most wines is between 45 degrees Fahrenheit and 65 degrees, although 55 degrees F is considered to be ideal.
