[lemonoman]

Does anyone have an idea of what kind of result I should expect? I think something like 5-10%...

Heinz Eazy Squirt Ketchup has 3 g of salt per 100 g of ketchup (3 %), according to http://www.foodcomm.org.uk/salt_may_03.htm

and the no-name ketchup in my fridge says it has 170 mg Sodium / 15 mL which, if all sodium comes from salt, is 0.43 g for 15 mL.  The density of ketchup is 1.4 g/mL, and so this is 0.43 g of salt per 21 g of Ketchup (0.43 / 21 = 0.02 = 2%)

So, to summarize, I'd expect 2-3% NaCl.


Density of Ketchup from www.lycoming.edu/chem/fall2003/110/exam1.htm

[tamim83]

Question, would you need to digest the ketchup sample to get rid
of the organic material?  We did something similar when we determined
how much zinc was in a brand of chicken broth using AAS.  We heated it
with concentrated nitric acid.  Would that work with the ketchup too? 
Just curious