Preserving

Preserving the wine to make it last is imperative for selling wines.

Wine can be preserved with sulfur dioxide or potassium sorbate, either after purification or sometimes before fermentation for white wines. More sulfur dioxide is found in white wines, rather than red, because they are usually sweeter and winemakers do not want too much sugar converting into alcohol after the wine has been bottled.

As a natural part of the fermentation process, a nominal amount of sulfites are produced anyway (about 5 to 9ppm or parts per million), but more are added and needed for commercial preservation.

Bacteria can easily ruin wine without preservatives.

Frequently, wine bottles have a phrase that reads “contains sulfates” on the back if it contains more than 10ppm sulfate. In the United States, law requires all wine labels to read “Contains Sulfites” in bold lettering.

The label is necessary in order to inform the consumers who may want a more organic wine or the consumers who may not be able to consume sulfates for medical reasons (sulfates can trigger severe asthma attacks in about 3% of those with asthma).

Most preservatives form an anti-oxidation or anti-microbial agent that can stop malolactic fermentation from continuing. Major bacteria that harm wine include acetobacter, Brettanomyces, lactobacillus, pediococcus, Ethyl Mercaptan, and hydrogen sulphide.

tags: preservation · preservative ·