Is the sulfate/chloride ratio important?

Some brewers rely on the sulfate/chloride ratio too much when gauging their mineral additions and their effect on beer flavor. The over reliance on that ratio by brewers is what drives me to caution against it's use. The sulfate/chloride ratio (or vice versa) is discussed in several well known texts that I know of. These include: Malting and Brewing Science and Handbook of Brewing. So the commercial brewing community has long known of that ratio.

The problem with the ratio is that it's effect on flavor is only properly reflected when the concentrations of those ions are modest. When the concentrations are very low, they aren't apparent enough in the beer taste to make a difference to the drinker. When those ion concentrations are high, they may overwhelm the beer flavor.

I coined a criterion that helps define when the sulfate/chloride ratio is likely to be useful and descriptive:

When the chloride concentration falls between about 25 and 100 ppm, the ratio can have a degree of validity.

The other problem I have with the ratio is its popular premise that it affects Maltiness or Bitterness. I dislike those descriptors. I feel the more accurate descriptors are: Fullness or Dryness. This latter description is actually presented in Malting and Brewing Science. Fullness does help malt character in the beer to exhibit and conversely, Dryness allows the perception of bitterness to come through better.

Having a better understanding of the ratio and its effect on beer flavor can help a brewer better understand the consequences of their mineral additions. Don't rely solely on the ratio. Be sure to look at the total concentrations and consider the ratio more valid when the chloride concentration falls within the limits above.