Yesterday I bought two bottles of liquor, one a Buffalo Trace (superb, soft and brandy-like), and a bottle of vodka that was on sale, called Elite, a Russian brand.
The Elite is sold is a plastic PET-type bottle, not my preferred packaging, but I thought I'd try it for $23.00.
Another reason was the label spoke of "silver filtering". I hadn't heard this term before. I thought it might refer to silver birch filtering, i.e., filtering through charcoal made from the silver birch tree, since at one time, a lot of vodka in East Europe was processed in this way.
But it doesn't, it refers to real silver added to activated charcoal which often today is made from coconut shell.
The idea is that adding silver, and other metals too like platinum and gold, increases the ability of the carbon to react with ethanol to produce esters and other pleasing compounds which give grain neutral spirits the final touches that turn it into vodka.
I found this website from a Russian company which specializes in this technology:
There are various sections to the site (listed in the bottle shape on the right) which are very interesting to read. As I interpret it, initially (late 1700's) it was found that using charcoal to leach grain spirit through would remove fusel oils and some of the rough taste of new spirit. The second stage to improve vodka quality was the development of continuous still rectification, which resulted in a high degree of purity but still left trace amounts of methanol and fusel oils in the distillate. A third stage was development of activated charcoal, which resulted in a more neutral, cleaner charcoal than simple wood-burned charcoal and had much greater absorbing qualities. In addition, this activated charcoal would react with the ethanol (probably the older charcoals did too but less efficiently) to produce esters which formed part of the vodka palate.
One of the points made is that modern spirit is so clean off the still that you want the activated carbon, not so much anymore to trap trace amounts of fusels, but to react with the ethanol (redox they call it) to assist to produce what people recognize as a typical vodka taste.
And the current stage according to this website, is that addition of silver and other metals to the activated charcoal greatly increases those chemical reactions which help produce the classic vodka taste. According to this website, vodka does have a characteristic taste and texture, "shaped" as it puts it by specific production methods. It isn't just an absence of taste, but rather a "typical" flavor and texture consumers recognize which has as one of its traits an estery note.
(Be that as it may, it is interesting to consider the Lincoln County Process in the light of the story of rectification as told here. Clearly it is an early 1800's technique, still using a wood charcoal (maple in its case), still taking days to complete for Jack Daniels anyway. The company clearly kept with the old ways despite many changes in technologies which followed. The new charred barrel itself is a type of charcoal filtering too of course, a very basic one that also is old and indeed created bourbon as a style of whiskey when using spirit distilled out at a low proof).
The language in this site seems carefully translated from the original Russian. The odd time it becomes awkward one can see what was meant.
It is all very interesting and I wonder if current North American vodka production presents analogies to what is discussed here. I believe activated charcoal is commonly used here to prepare GNS to be vodka, but I am not sure about the addition of metals to the carbon or whether there is universal agreement that it improves the result of the filtering.
I must say the Elite is really good, IMO as good as any name brand I've had that costs much more and better in some cases.