title_body: Cold brewing at varying temperatures - How does steeping temperature affect extraction?
upvoted_answer: Okay, so what if I told you, that I sell a lot of cold brew at my shop, and have had success with 4-hour steeps. 
  
  I've tried a bunch of stuff, and I've realized that since the temp is really low (mild to cold), it barely makes a difference in TASTE. The biggest factor is oversteeping (like, 48hours up brew), as it can make your cold brew sour. But as a rule of thumb and for sanity of the production team, I go for cold water and steep for 8-15 hours, depending on the time of day it's made.