I'm glad you cleared that up.
I've seen steam driven cooking kettles used for food -- and explosives. ( TNT is usually melted this way to produce munitions. )
Because of the nature of pressure and heat and the above listed steam table data sheets, one can dial in a remarkable steady heat -- without temperature spikes.
This is why such schemes are exclusively used to melt chocolates.
There is another type of 'steam table' in use: to prep oriental foods prior to freeze wrapping. The various vegetables are steam processed -- at higher temperatures than chocolate -- until 'just so' -- and then flash frozen.
Such food processing steam is typically electrically powered... lending itself to process control, too. Whatever the mechanism, any steam generator that does not have an absolutely pure feed corrodes into junk with amazing speed.
For locomotive buffs, the front face of the old steam locomotives existed entirely as an access point for the anti-corrosion crews. If you inspect them closely, you can see that the entire front can be unbolted, removed.
Thereafter the boys have to ream out any corrosion from the endless boiler tubes. This one process absorbed the bulk of all of the maintenance budgets of the era. Most locos were treated two to four times a month -- or even more in areas of bad water. It was so bad in the American southern desert that the SP hauled in pure water for certain locations. (!)
Sorry, my bad, Reno.
