Results 1 to 5 of 5

Thread: Cloudy HLP Tests

  1. #1
    Join Date
    Jan 2015
    Location
    Gulfport, MS
    Posts
    11

    Cloudy HLP Tests

    We are having some troubles with our HLP testing process. Some samples come up cloudy. There doesn't appear to be growth of colonies but the liquid is definitely cloudy. We've had some of these beers sent to a lab and they came up clean. Why would our tests be coming back cloudy?

  2. #2
    Join Date
    Jul 2017
    Location
    Halifax, Nova Scotia, Canada
    Posts
    3
    Quote Originally Posted by GulfSide View Post
    We are having some troubles with our HLP testing process. Some samples come up cloudy. There doesn't appear to be growth of colonies but the liquid is definitely cloudy. We've had some of these beers sent to a lab and they came up clean. Why would our tests be coming back cloudy?
    If you're sample still has yeast in suspension it will turn the HLP cloudy. I pop mine in a fridge for at least half an hour before using but samples taken in early fermentation can still leave me with cloudy tubes if I don't give the yeast enough time to settle.

  3. #3
    Join Date
    Oct 2017
    Location
    -
    Posts
    8
    This is good to know! I've had some tests come up cloudy as well. So will a positive for lacto or pedio always look like whole colonies in suspension opposed to haziness?


    -Ziggy


    Quote Originally Posted by Ploughman View Post
    If you're sample still has yeast in suspension it will turn the HLP cloudy. I pop mine in a fridge for at least half an hour before using but samples taken in early fermentation can still leave me with cloudy tubes if I don't give the yeast enough time to settle.

  4. #4
    Join Date
    Jul 2017
    Location
    Halifax, Nova Scotia, Canada
    Posts
    3
    Quote Originally Posted by ziggy beersci View Post
    This is good to know! I've had some tests come up cloudy as well. So will a positive for lacto or pedio always look like whole colonies in suspension opposed to haziness?


    -Ziggy
    Yeah, in my experience any growth has been easily distinguishable. May take up to 5-7 days to determine the colony shape and distinguish between pedio or lacto. I guess if you had a very high level of lacto contamination the colonies could be very dense and appear as haze however that would take days to happen. The cyclohexamide in the media kills the yeast so when that's contributing to haze the tube will look like that as soon as the media sets.

  5. #5
    Join Date
    Oct 2012
    Location
    Palatine, IL
    Posts
    92
    Try diluting your samples. If it's yeast, the haze will lessen. If it's a bunch of colonies, they will be more distinct.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •