On the label practically of any wine, irrespective of its cost and origin, it is possible to meet the instruction on sulfur dioxide content now. This substance also known as sulphurous anhydride or dioxide of sulfur, belongs to the class toxic therefore need of addition of dioxide of sulfur in wine often raises doubts. However use of sulphurous anhydride by production of grape wines is quite justified and is explained by the objective reasons.
Why sulfur dioxide is necessary?
Sulphurous anhydride was applied since antique times. In the Middle Ages the fumigating of wine casks by sulfuric matches for the best preservation of noble drink was widely used. Medieval wine makers realized toxicity of this chemical therefore fumigating of wine casks sulfur was forbidden or limited more than once to save health of consumers.
Nevertheless couldn't refuse sulphurous anhydride, and at the beginning of last its century began to apply in production of wine, bringing this substance in wine materials or in ready wine to avoid reproduction of harmful bacteria, a mold and wild yeast. Dioxide of sulfur not only stabilizes microflora of wine and wine materials, without allowing in them bacterial changes, but also prevents oxidation. Exactly thanks to sulphurous anhydride wine keeps color, taste and aroma.
Also dioxide of sulfur is capable to stimulate wine fermentation as culture yeast under its influence doesn't perish.
It wasn't succeeded to find adequate replacement to sulphurous anhydride still – substances with smaller toxicity have no necessary antibacterial and antioxidant properties, worsen quality of drink. Practically only producers of expensive organic wines do without addition of dioxide of sulfur or its minimum quantity – grapes for their production grow in the eco-friendly area, at production of drink chemicals and the modern equipment aren't applied, fermentation goes a natural way. But even organic wines contain a small amount of the sulphurous anhydride which is emitted in the course of fermentation.
The quality depends on quantity
Despite all the useful qualities, sulphurous anhydride remains the toxic substance capable in high doses to cause serious violations of health, and strong allergen. However in the doses causing undesirable reactions, this substance to wine is just not added. Its standards of the contents in wine don't exceed 160-400 milligrams on drink liter. At the same time producers try to lower whenever possible sulfur dioxide content in a ready-made product as its surplus badly affects gustatory qualities of wine.
The producer has the right not to specify on the label of wine whether there is at it a sulphurous anhydride, however, if you buy not rare organic wine, preservative with guarantee contains in drink.
If at production of wine the technological process was broken, its taste can change – the tart metal shade unusual for this wine, an unpleasant odor is observed. Consumption of such drink with high probability will make the headache, sick, weight in a stomach which are often taken for hangover symptoms. It is better for allergic persons not to use such product in general – the probability of undesirable reactions (up to suffocation) increases several times.