From way I understand it, in order to preserve enough meat and vegetables over the winter, you need hundreds of kg of common table salt.
Hundreds of kg of salt sound very expensive to me.
How did, say, a Hungarian or Russian serf afford this before industrialization?
There is certainly more that can be said to answer this specific question, but there are some similar previous answers that might be helpful.
u/Pabst_Blue_Gibbon and u/Noble_Devil_Boruta answered Salt used to be worth its weight in gold. Now we liberally spray it onto city streets to melt ice. Where did all this salt come from?
and I know that in the Middle Ages salt was an extremely valuable product, was it the same in the Mediteranean regions despite being so close to the sea? answered by u/wotan_weevil