After chemist Louis Pasteur (1822-1895) designated process for killing spoilage-causing microorganisms in liquids or food. Pasteur thus solved a big problem for the winemakers at that time. The bottled wines were often not stable in the bottle. It kept coming up secondary fermentation or the wines got one Vinegar- or Lactic acid sting, By heating to high temperatures yeasts. bacteria (e.g. lactic acid. acetic acid, Salmonella) and molds killed and thus the products are made sterile and durable. However, certain microorganisms require high temperatures. Fruit juices ( grape juice ), Vegetable juices, milk and beer pasteurized. This takes place at temperatures between at least 60 to a maximum of 100 ° Celsius in different durations (a few seconds to 30 minutes). The vitamins are largely preserved, but vitamin C is destroyed. When heated to over 100 ° Celsius to kill heat-resistant bacteria and virus one speaks of sterilization,
Pasteurization is rare in wine today, and is also frowned upon by many producers. Because if used improperly, the wine can Aroma be adversely affected. Such wines can already at temperatures below the boiling point Kochton have what with strong expression as wine faults is classified. The reason for this is the volatilization caused by the heat flavorings, It can also be caused by dehydration sugar for the formation of hydroxymethylfurfural (HMF) come. In fruit juices, honey and milk, a high HMF value is a sign of poor quality. However, not all changes need to be negative. There are changes that normally take place at the bottle aging run much slower. The wine can be positively aged or aged Act.
By today's Hygiene standard or the sophisticated one filtration technology you can do without it today. If anything, pasteurization is especially common with simpler wines as well sweet reserves for the purpose of durability carried out. The wine should be absolutely clear; on hefetrüber Wine must not be pasteurized. Therefore, the yeast sediment after the fermentation subtracted from. Pasteurization is carried out by rapid heating to 65 to 75 ° Celsius (with a sweet reserve 85 ° Celsius) for a period of about three to five minutes. This is followed by rapid cooling to 25 to 30 ° Celsius. Pasteurization can also be useful grape be from rotten grapes to completely eliminate the flora from bacteria and wild yeast.
Wine is pasteurized either immediately before or more often after bottling, After all, the fewer work steps that are necessary afterwards, the less there is a risk that the wine will be accidentally contaminated with microorganisms after pasteurization. In the case of rapid pasteurization (flash pasteurization, eclair pasteurization) bottles just warmed up for 15 to 30 seconds. In tunnel pasteurization using large machines, the wine bottles go through several temperature landscapes. They are transported through a tunnel (tube) and heated by means of spray nozzles with water of different temperatures and then cooled again.
Complete lists of the numerous vinification measures or cellar techniques, as well as the wine, sparkling wine and distillate types regulated by wine law are under the keyword winemaking contain. There is extensive wine law information under the keyword wine law,