Thank you Lpink for the Piccalilli relish for Sienna 98. I will have a ton of green tomatoes at some point. Great recipe to use some up.
In the post, "---"Non-reactive" means not aluminum or cast iron, which will "react" with the vinegar to give an off taste to your relish. Enamel, non-stick or stainless steel are fine.---"
I seem to remember differently from Chemistry 101 about aluminum. Aluminum forms protective oxide immediately on exposed surfaces which prevents further chemical reaction when it comes to weak acid such as acetic acid. That's why aluminum containers are commonly used to store and transport the acid.
So I did an experiment.
Using an aluminum cup with a sheet of aluminum foil, I measured the weight (1.03 oz), and then I cooked the foil in pure vinegar for three hours. After, the cup and foil were let soaking for more than 36 hour.
I cleaned and dried the cup and foil and measured again, the weight was 1.03 oz.
I also examined the foil under a high power microscope. There were no visible pitting or corrosion on the shinny or mat finishes on the aluminum foil, compared with the untreated side of the foil.
We all know washing aluminum with mild alkali (basic) such as soap and dish washing liquid have no effect on aluminum, however, Easy Off oven cleaner will etch aluminum quickly. Aluminum will also react with strong acids such as hydrochloric acid.
Just being curious.