Hsu's Lactobacillus & Pediococcus Test Result Interpretation

[mikedavis1962]

Learned the hard way we need to do a better job in lab testing. Lost a batch of our house IPA to what I am reasonably sure was pediococcus. At least all symptoms point in that direction. Currently have 4 other batches in FV's that we feel were at risk based on timing and other factors. Purchased the HLP Medium, sterile tubes, pipettes etc. and tested pursuant to instructions using sterile technique to the greatest extent possible. The good news is after 4 days we have no sign of lacto or pedio. Samples are perfectly clear. The bad news is all four samples have grown a membrane on the top of the liquid. Please see posted photographs. My research indicates the presence of an aerobic bacteria of some sort. My questions are as follows: 1. What are everyone's thoughts on my assumption?, 2. If this is an aerobic bacteria, are these batches completely wasted? We only keg and from this point forward there should be no to introduction of O2. Thoughts, ideas and suggestions all welcome and greatly appreciated.

[wrbQC]

Hi,

I know this is a late reply and I hope you have gotten an answer by now but I have read that acetobacter can grow on the top of HLP medium in the tube. You could also pull some out for a gram stain and a quick catalase test.