title_body: What molds grow in brewed coffee?
upvoted_answer: Though I don't have any articles on the matter, I can certainly say I've found cups of coffee that I had forgotten that are only maybe a week old with mold growing in them. I'd assume it gets contaminated so quickly, because of its sugar content. It might just be a coincidence, but it seems to happen more readily with coffee that I brew over ice. I press my areopress directly over ice, I've heard this reduces the acidity. Which would make sense, as acidity usually wards off mold. I leave all of my coffee black and unsweetened, so it is not dairy or added sugars that are causing this.
  
  Perhaps try variating your brewing process. I'd be especially keen on the pH. Maybe there are some spores which will not grow in environments below a certain pH.