Will sodium citrate harm yeast?

try this site for flavors ingredients

How could citric acid be OK and sodium citrate not be?

Pierre

Hi, Pierre. I'm not a chemist so I don't know how the two compare. I had said that I "think" citric acid is okay ... and I said that because it is an acid, and I know that yeast can tolerate a certain amount of acidity -- such as when an acid wash is done -- and I was also assuming that the amount/strength of acid in something we can eat right out of the can, if we wish, would be sufficiently diluted by mixing it in wort to therefore make it less than 1/15th of its concentration in the can.

Cheers.

Thanks, S. I'm glad you pointed that site out to me for future reference, but I'm looking at two cans of cherries on my desk which are tempting, versus putting off this experiment for perhaps a couple of weeks. And I consider that fruit beer was being made long before there were any commercial extracts available, and is still being made successfully today with fresh or frozen fruit; two examples are award winning recipes for cherry ale and strawberry ale in my brewing book. So my primary concern is the sodium citrate ... and now that I think of it, another issue: since canned fruit has presumably been cooked already as part of the canning process -- (I don't know if canning in "cans" is the same as in "mason jars") -- the pectins are likely to have already been set and will cause haze in my beer. But since I'm usually far less concerned with the looks of my beer than how it smells and tastes, I might still give this a go just to see how it works out. Just in case, since everything inside the can should be sterile, I'll sanitize my blender so I can puree and pour into the fermenter rather than add to the boil and expose to any further heat.

Cheers.

They are pretty much the same thing once put in a biological liquid. Citric acid will react with weak bases to form citrates.

The acidity of citric acid is probably irrelevant (the quantities in question will not affect the pH); instead, it is the ability of citrate to grab trace contamination by metals such as iron and copper that is useful: by removing such metals, it inhibits the ability of some bacteria (and loose enzymes) to spoil foodstuffs.

Pierre

Thanks, Pierre. So can I interpret that to mean that trace amounts of sodium citrate will not harm the yeast or hurt my beer?

Right. As a matter of fact (it's not true of all additives or preservatives) citrate will very likely be metabolized by the yeast, since it is an intermediary in cell respiration (the citric acid, or Krebs, cycle.)

Pierre