I tried my bitter after 4 days, it's done fermenting but stinks of sulfur. I am very wary of cold crashing it. I do think the yeast do some clean up. I'll try it again after a week and see if it's gone. It could be yeast dependent even within ales and lagers.
I don't suffer much from sulphury ferments. They have occasionally occurred but at an ignorable level. But "four days"? I've never tried to drink my beer that early (7 or 8 days perhaps, apart from sips as ongoing Quality Control!). I think
@Weizenberg answered that issue.
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I liked the article
@Sadfield posted. Suggested the attributes of the yeasts I often use all go together; high speed, lowish attenuation (shy of "malt-triose" sugars), fast clearing, most of which makes them unpopular these days, but they suit me (I
generally dislike cold, flinty, thin, and fizzy beers ... and the term "cold-crashing" turns my stomach, give me reconstituted fish guts, isinglass, any day).
Sorry, I mentioned earlier that I'd previously found the yeast in my current brew a bit slow (MJ's M36 "Liberty Bell") but that's one I'm only just trying, it was M44 ("US West Coast") I'd normally use in this particular beer. But I've jinxed the M36 now and it's acting much like the M44 (after 36 hours it's only cleared 15 gravity units, the S-33 in my graphed example above had done over 30 units in that time). Could of course be Mangrove Jack only give you a paltry 10g, not 11.5g like others?
But, as
@Sadfield said "pitching the correct amount of viable yeast" is probably the key to speed of fermentation. Use adequate in-date dried yeast (although my S-33 in the graph above was two months past it!) and I always use a starter and pitch calculator for liquid yeasts (no "smack, chuck it in, and cross your fingers" for me). If using my small fermenter (30L) I never bother aerating (dried yeast is packed with enough products created with oxygen before it is dried, and so has liquid yeast if fresh out of an
agitated starter with access to air/O
2); but I keep the OG below 1.050 to get away with that.