Is yeast/trub separation really necessary in harvesting?

[Datchew]

I've had lots of success harvesting yeast. Typically, I just use the autosiphon to suck about 5 oz into a glass container after racking to keg or bottling bucket. Just suck it right off the top of the primary.

Yes, it has some trub mixed in, but I use it quickly again and figure it's just more flavor. And in doing this, the next batch(es) have been fabulous.

But if you leave this harvested sample in the fridge for 3 months with some trub mixed in... does it matter?
Do you really even need to separate the yeast from the trub for storage?

 

[Suthrncomfrt1884]

This method works fine, but you will have off flavors in lighter beers because of it. It's like leaving your beer in primary for 3 months.

The only time I do this is when I'm going from a light beer to a heavier or highly hopped beer. I usually brew the same day I plan on racking to a keg and then rack the new wort on top of the yeast cake.

 

[dstar26t]

If you're not going to wash it, try to use it within 2 weeks. I've used unwashed yeast that was 4 weeks old and didn't like the results (no starter but the proper amount of viable cells according to Mr.Malty). Slower ferment and off flavors.

 

[masonsjax]

I never separate, and sometimes it's several months between uses. Never had any problems, but I always make a starter.

 

[petep1980]

I separate, but I wonder how good I really am at it. I always make a starter and other than some winey tastes in a Kolsch re-use I have had great success.