I have a question concerning brewing salts. I’m coming up on the one year mark since incorporating them into my brew days (it would be hard to overstate how much learning my way around Bru’n Water has benefited my beers) and realized that I’ve been using the same batch of salts that I originally purchased a year ago. I mostly use Calcium Chloride, Gypsum, Pickling Lime and Lactic Acid – can anyone recommend an expiration date for these items? I haven’t had any issues, but wanted to head off any potential problems due to keeping them around for too long. FWIW, I keep them sealed in Ziploc bags.
they should last indefinitely if you keep them dry/or avoid exposing them to extra moisture in the case of the lactic acid. Gypsum comes from deposits that can be millions of years old. Probably not going to change in our lifetimes.
Pickling lime and calcium chloride are affected by atmospheric moisture. Pickling lime will revert to chalk when exposed to atmospheric moisture for a long time. This is probably not a big problem, but something that you should be aware of. Keep the lime dry.
Calcium chloride is very hygroscopic. That means it readily sucks up moisture from the air. This is what ‘Damp Rid’ is made of and we know that it is effective in dehumidifying. The fact that calcium chloride sucks up water does not make it ineffective in delivering the calcium and chloride ions we want in our water. The problem is that the molecular weight of the material changes and we won’t deliver the amount of ions we think we are. There are several stages in the hydration state of calcium chloride, so it is difficult predict what the unit weight is if you allow the stuff to be exposed to atmospheric moisture.
The rest of the minerals we commonly use in water adjustment are relatively stable. Don’t worry about them.
I had some calcium chloride get mushy. I had probably had it for 1-2 years and it was in a Ziploc bag. I asked about it at the time and got some responses similar to Martin’s so I picked up some new stuff and put into into an old, empty, cleaned PBW container with a screw-on lid. I keep it as tight as I can and that CaCl has been in that container for over a year now and it’s very dry, light and loose. I also wondered about lactic acid. I had a bottle that was probably 2-3 years old and maybe hallway gone. I decided to pitch it and just get a new one after some people suggested that it does have a shelf life.
It looks like I’m in pretty good shape for the time being – no mushy calcium chloride or anything of the like. Brewing salts being relatively inexpensive, I think I may just start over every year or two, just to play it safe.
I found out early on about storage of minerals as I had the same question regarding loss of weight or other degradation when looking at water manipulation years ago and was surprised to find out that indeed there is a few things to do. Such as all you need to do with CaCl is keep it tightly lidded, the same for lime as Martin explained already. I have a few year old pound of Calcium chloride and the last half of it is all loose pebbles/granules every time I need some.
Edit: Now that I read Kens last post, I have to wonder now if Martin or anyone else with knowledge can speak to lactic 88%, phosphoric 10% or other acids/ concentration levels etc… Concerning degradation or loss of effectiveness over time? Or do they stay stable for long periods of time?
If there is degradation, then what are some rules of thumb for storage shelf life of liquid acids?
The acids should be stable for months to years. 88% lactic acid might be slightly hygroscopic but I don’t think you’ll change the concentration by even 1%.
