How to Know if Culture is Viable after Delivery

[soniaR]

I just received delivery of 3 cultures I ordered on Friday, via USPS priority, in mailman's truck all day until delivered today, Monday, at 3:00 pm. I took the temp of the culture bags right away: 83 F. How can I know if these are viable? And how can I get around this in the future? The vendor was cheesemaking.com.

[cheesehead94]

I don't have a true answer to your question, but I just wanted to say that something almost identical happened to me once and they were fine.

[5ittingduck]

As a rule if they get a bit warm that won't kill them, it will just reduce the lifespan of the culture a bit.  Normally you would use the batch up before it would run "out of puff".
Almost all of my cultures are delivered by post, and I have only had one fail before I used them up.
To directly answer your question, just warm a cup of milk to blood temperature, add a tiny grain of culture and stir.  Wait an hour and add a drop of rennet, it will eventually set if the culture is good.
Basically make a tiny test batch of curds.  Even easier if you have a Ph meter, just add culture and check later to see if the Ph has dropped.

[River Bottom Farm]

Yes just do a test batch and monitor
pH. You can compare to data sheets and pH curves here: https://cheeseforum.org/forum/index.php/board,172.0.html if you want to be technical.