Replacing Cultures

[ellenspn]

Can't decide since my feta culture seems to be weak at best if I should replace all my cultures, even the unopened ones.  since most of them are over 4 years old. They have been stored in freezer the house which is part of my fridge.

Any thoughts?

[Duntov]

If they are just weak maybe you can use double the amount?

[John@PC]

Tiarella probably is the best to answer this question because she has often used outdated cultures.  I stopped making cheese in Nov. 2015 and just started back using my old cultures that are 3 years old and didn't have any problems including the adjuncts I used.  If you have a pH meter you can put 1/32 tsp. of your culture in 1 cup of warm milk and if cultures are still virile your pH should drop steadily.  I did this test with the MM100 I had and after 2 hours pH was 5.8.  I went ahead and let it gel, cut and drained whey and chilled.  Tasted like a mild / low fat sour cream .

[ellenspn]

Thanks! I do have a ph meter and will test what I have 

[Boofer]

Ellen, some of my cultures are five years old or more. I keep them vacuum-sealed in the freezer.

My PRB18 liquid blue mold has a 2011 date and it worked well recently. Here is another example. I keep it in the fridge, not the freezer.

Perhaps the cultures can't tell time.

-Boofer-

[John@PC]

Sorry Boofer - I saw your post on another thread after I made my comment about who was best one to ask about "old cultures".  Looks like you may have Katherine beat.  Anyway it gives me an opportunity to tell you and all the other "older cultures" and even the new ones how much I your advice is appreciated. 

[Stella]

I'm a little embarrassed but some of my cultures are almost 9 years old( I inherited a slew of cultures from a dairy I worked at, they had done some experiments and were going to throw them out, they are still good!) I spoke to a supplier about it( they are all Chr.Hansen freeze dried cultures) and he said that as long as they are loose( not clumped) and ivory color they should be ok

[Gregore]

I almost always make a starter culture over night near an oven light , then use it at 1.5 percent by weight .

And some of my cultures are even clumped from being in the freezer for so long  , as long as the milk gels at least a little  You know it is acid enough  to use as a starter , freeze the extra  for next make

[Gregore]

I should add that the best reason for doing it this way is you do not have to wait for the cultures to hydride and wake up  before adding rennet ( save an hour of time every make ) if it is freshly made , with freezer cubes , maybe wait 1/2 hr before rennet .