Weinstein – Achieve a faster stabilization by cooling
The stability of a crystal wine means for the practitioner usually Weinstein stability. At Weinstein crystals occur in various forms, but can be clearly demonstrated analytically. (Photos: Daniel Powder) is the natural crystalline precipitates in the young wine, it contains 90 percent of tartar (potassium hydrogen tartrate), the acidic potassium salt of tartaric acid. He shows how finely crystalline, brownish precipitate that tends to be for storage and Schülpenbildung and slightly acidic taste. The proportion of the calcium compound (calcium tartrate) is compared with the potassium salt generally low. The natural Calciumtartratausscheidung occurs so rarely.
Although the quality of a wine has to do with the formation of tartar little influence on the crystal clarity of a drink, lower the drinking pleasure of consumers and are often mistakenly viewed as a mistake.
Weinstein, as well as calcium tartrate are in alcoholic solutions with increasing alcohol content and decreasing temperature, less soluble, resulting in the wine to a “saturation state” and to precipitate. The tartaric acid crystals fall to the ground. This precipitation may by various constituents of the wine (see box) will be promoted or retarded.
Various factors influence crystallization excretions:
- Tartaric acid content,
- Potassium content,
- Calcium content,
- Colloid content,
- Filtration technology,
- Degree of filtration
The formation of tartar can stop by technical processes, you can wine “stabilize”. W hen the traditional methods of stabilization are:
Addition of metatartaric (high molecular polymerized tartaric acid):
The Crystal formation, but only for a period of about six to ten
Months prevented. According to the Swiss legislation, the use of meta-tartaric acid to stabilize the wine is allowed, with the concentration, in practice at 0.1 g / liter. The use of meta-tartaric acid is especially White wine, but also in red wine and rosé popular for decades. However, this technique should be limited to those wines which are consumed within 1-2 years. By combining various polymeric materials, the stability of metatartaric be extended also to the wine storage. The product MetaGum the metatartaric was supplemented by gum arabic, and thus extends the protection significantly.
By the addition of finely ground seed crystals Excretion accelerates crystallization. Typically, 4 g / l tartaric crystals with simultaneous cooling to about 0 ° C (temperature stability) was added. Within 2 hours, excess Weinstein outsourced to the Seeded on. The crystals are then separated. Contact Weinstein can be used multiple times. The effectiveness decreases, however after each use. Repeated grinding of the contact tartrate is possible and extended the operating time of the crystals. Without cooling, this process takes about two weeks. Occasional stirring is necessary.
Stabilization by cooling:
After pre-filtration to clean sensory wines are cooled. The cooling is initiated as soon as possible, which promotes the onset of crystallization. The temperature is, if possible, kept for about two weeks to + 4 o C. Then a stability test is performed. Is he in order, the basement will be heated again to 10 to 12 o C. “Movements” of the wine seem conducive to crystallization. The likelihood that meet the reactants is then increased. In most cases now Weinstein stability has occurred.
There are known to us other recommendations, but ultimately it’s all about the following:
Faster stabilization is only by lower temperatures (Recommendation: Do not under – 4 ° C) and with the addition of contact Weinstein possible. Known methods, for example, space cooling, in tanks with brine, cooling coils or cooling units. Quality-conscious winemakers, however, avoid – in order to preserve their wine – for example, the severe cooling of the wine to below – 6 ° C so that the Weinstein fails and can be filtered off.
Electrodialysis treatment to prevent the precipitation of tartar is allowed in Germany. However, to be determined according to application conditions and for the time being, especially for table wines and quality wines psr by Action of an electric field, the ions of the wine in the direction Anode or cathode moves. They hit diffuse through membranes and, if they are able. On the other hand, they are of irrigation fluid away. The potassium ions migrate towards the cathode and tartrate direction Anode. In this way the concentration of tartar is reduced.
Use of cold
A responsible use of “cold” also brings in the Weinstein-stabilization best results. It urges, however, for reasons of cost, an overarching commitment to all sectors involved in viticulture. Our team of experts from the wine-growing and cold-air shows like the savings and potential applications.