Amber malt has a strong distinctive flavor. I use it in the amount of 6 ounces in my IPA and it's and it's still discernible.
I'd use it in small quantities to make "richer" flavored IPAs and APAs and stouts. It's a great malt, but if you don't make a ton of porters, you'll be using it 6-8 ounces at a time.
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