I made some persimmon butter with extremely ripe hachiya persimmons. They were sweet and not at all astringent. I had read that they get more astringent when cooked but I thought I'd give it a shot. The butter is very tasty but has more astringency than I, personally, like. It's like a very astringent black tea. I found something online that said if you add baking powder to persimmon purée when cooking that it helps the astringency. I threw some in and am letting it cook a bit to see if it helps.
I was planning to can this butter in a hot water bath. But I can't find any information on canning with baking powder. I assume it's probably fine but I just want to make sure. I've been canning frequently for about a year. This is the first time I'm winging it on a recipe. Any help would be appreciated. Thanks!