Harvest Yeast, Wash then Pitch?

[smeltz]

I've been reading a lot about this and had a question, cause Im a cheapskate. If I harvest the yeast from the primary, wash it and the pitch it in my cooled wort(a new batch of beer), will the yeast still be active? Basically, Im trying to save money by not using a bunch of DME(~$2.50 for a 10gal batch) needed to make a starter.

Thanks in advance!

 

[LLBeanJ]

How old is the yeast? If you use it within a couple of weeks, you can harvest and direct-pitch the slurry without washing it.

 

[smeltz]

Is it relatively safe to say that I won't get any bad flavors from the slurry? If there is a chance of bad flavors and I wash the yeast first, then direct- pitch it the same day, will the yeast go into "hibernation" and not start out well in the new batch? Also, if my OG is around 1.070 is it still safe to harvest the yeast?

 

[rodwha]

My understanding is that using an unwashed slurry can add a little of the flavor profile from the previous batch. So if the old and new are quite similar it isn't really an issue, nor would adding it to a darker beer, but you wouldn't want to use the slurry from a stout to make a pale.

 

[LLBeanJ]

I personally wouldn't re-use yeast that had fermented a 1.070 beer. 1.060 is about the upper limit here, thought there is a bit of grey area as far as how high is too high. The higher the OG, the more stress the yeast have endured. I like to limit it to the mid 1.050s myself. This applies to both direct pitching and washing.

As far as flavors carrying over, yes, it can happen. I don't think it's so much "bad" flavors, but rather undesirable flavors. If you use yeast harvested from an IPA or IIPA to ferment a less flavorful style, you could bring some flavors from the hops that you may not want. This also applies to both direct pitching and washing.

So, how do you get around all of this and still reuse yeast? Fortunately, it's not at all hard. I do it all the time. I also NEVER wash yeast because it's a pain in the arse and there are much easier ways to get clean yeast.

To have clean yeast for your yeast bank, instead of washing, make an oversized starter and save a little (25-50B cells) in a sanitized mason jar to be used for another starter later. This will give you clean yeast that has not been stressed by fermentation and has not been exposed to hops.

To minimize the number of starters you need to make, plan your brews so that you do a lower OG, less hoppy brew first to be followed with a bigger or higher IBU beer afterward. This will allow you to direct pitch slurry without having to be concerned too much about yeast health or unwanted flavors carrying over. You can also do this with dry yeast, rendering a starter unnecessary.

 

[rodwha]

Larger starters to save a portion is exactly what I've been doing as I found the advice here.

 

[NathPowe]

+1 for not washing yeast. Just plan your brew schedule so that you can harvest slurry from lower gravity beers. I just throw it in a mason jar and pop it in the frig. If you use it within a week or two you should be good to go.

Cheers.