I just bought some buttermilk starter culture, just like I buy the yogurt or cheese culture. You can keep reusing and reusing, but i always start with a culture. Mine will go for months but sometimes I run out, so i jsut use a little bought culture to start it up again. Just put some in raw milk and presto, raw buttermilk. Then use that to sour your cream. If you have creme frache you can use that for sour cream too.
Last time I tried this it wasn't with raw cream but it was organic I just used a few tablespoons of yogurt and let it culture in my warm oven. Had 2 quarts of sour cream in about 12 hours. Boy we were sick of sour cream by the time we ate all of that! <img alt="" class="inlineimg" src="http://www.mothering.com/discussions/images/smilies/lol.gif" style="border:0px solid;" title="lol">
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<div>Originally Posted by <strong>quietserena</strong> <a href="/community/forum/post/7974890"><img alt="View Post" class="inlineimg" src="/community/img/forum/go_quote.gif" style="border:0px solid;"></a></div>
<div style="font-style:italic;">Last time I tried this it wasn't with raw cream but it was organic I just used a few tablespoons of yogurt and let it culture in my warm oven. Had 2 quarts of sour cream in about 12 hours.</div>
I've done this with kefir. Mix a few tbsps of plain kefir into the cream and let culture at room temperature overnight or up to a day and then stir well. I like to culture my cream sometimes before making iced cream.