freshness questions

Cream of Tartar and baking soda should remain fresh, as long as they are not damp or caked. Probably OK, even if you have to re-powder them.

Baking powder will lose its raising power, if it absorbs any moisture. You should be able to test it my dropping a quarter teaspoonful into some water. If it fizzes and leaves litte residue, it's fine. Dave

Thank you :-) I knew one could be tested with the water, but didn't remember which.

Bobbett

I second that- you want your stuff to come out the best possible- not worth risking using old stuff for something that may not turn out as you wanted

I agree with Bob. Baking soda stays good forever (at least I hope so judging by the amount I have.) I do not know about Cream of Tartar, but the can of baking powder I just bought has an expiration date of Feb. 2008. I always buy fresh baking powder in November for my Christmas baking. It might be ok, but it is just about the cheapest ingredient so why take chances.

This is what Penzey's says on it's site Cream of Tartar Cream of tartar is used to stabilize delicate foods like meringue toppings and other baked egg white products. Natural tartaric acid. From France.

I have on hand several bottles of tartaric acid; none of which has a 'use by' date. (I use it for cheesemaking.) Dee

Actuall;y, I think I mis-spoke - perhaos Roy / Chembake will step in and correct me - I think it's the bicarbonate component, not the acid component. Some use Ammonium Bicarbonate, I believe, and probably Tartaric Acid...

Dave

I believe cream of tartar and tartaric acid are not the same thing, correct??

You're right, they're not the same thing.

True - cream of tartar is potassium hydrogen tartrate, which hydrolyzes to release tartaric acid in solution, I believe...

Dave

Hello Dave, I would add that Ammonium bicarbonate is used as the leavening agent( itself ) in low moisture baked goods such as cookies because of its unique nature to promote cookie spread while at the same time contributing to leavening: Schematically NH4HCO3 +HEAT = NH3( causes the cookie to spread) + CO2 and H2O( both of which contribute to the leavening effect. It is not widely used in bakery products due to the water solubility of ammonia and if the baked product is of high moisture content there is plenty of residual ammonia left in the baked food making it unpalatable.

In comparison sodium bicarbonate does release minimal amount of CO2 by itself as a leavening agent unless there is an acid component present such as for example butter milk, or fruit juice. Baking soda is best used with acid salt( such as cream of tartar, calcium acid phosphate, sodium pyrophosphate, sodium aluminum sulfate).

Ammonium bicarbonate is not that stable for use in baking powder composition aside from being very hygroscopic, Tartaric acid is too fast to be used in baking powder, cream of tartar is a bit slower andmore practical for home made baking powder. Cream of tartar is indeed used to stabilize egg white foams due to its acidulant effect.