Which food things make a difference, which don't?

[ericd]

fresh fish v frozen fish
single malt scotch v all others
top quality ice cream v normal ice cream

[theBruiser500]

organic tomatos. they smell like real good yummies right from the home garden, so good.

[posnera]

For salt, I only use kosher salt for cooking (baking gets regular salt). If you are adding salt to top off something and it will stay crystallized, then there is a difference in sea salt, fleur-de-sel, or any other "fancy" salt. If it is going to dissolve then you are just wasting money.