Re pitch US-05 from 1 gallon batches?

Happy weekend homebrewers! Great news - I have my first batch fermenting after a few years away from the hobby. This has me planning out the next handful of brews - the goal is to brew a small batch every week or two to get some more recipes and techniques under my belt quickly.

My question today is about reusing yeast. I think I'm happy using US-05 for the next half dozen or more batches, given its neutral flavor profile and high attenuation, and that's in my current fermenter. What process would you recommend for harvesting and re pitching, likely with a small starter as well? How would I make a starter from yeast harvested the previous week, and how would that change if I was fermenting different brews from week to week?

Thanks for any advice!

If I was making small batches with recently procured slurry, I wouldn't bother with a starter. I'd probably pitch half of the first collected slurry in the second brew. The harvested yeast from the second brew would get stored with the first, now-smaller jar of slurry, and so on - giving you more slurry with each batch of beer.

Harvesting and yeast washing techniques are easy to look up - YouTube, Google, etc.

Here you go.

I understand the need to practice a technique like this, but aren't packets of US-05 super cheap?

Yeah, I don't quite see why you're doing this, unless the whole idea is to practice on small volume.

To answer a few Qs I expected:
1) $2.50 + shipping for the yeast to go in a gallon of beer is a pretty significant cost, probably a quarter of the cost of my ingredients or more.
2) ditto on the need to practice.

So what's the deal with washing yeast? Is this something I should consider with the slurry from hoppy beers, as I understand some hops inevitably make it into the trub? I'm probably getting close to that 8% mark I read about being dangerous for some yeasts for some of the batches I'll make in the next few months as well.. are those both types of batches I should just ditch the cake and start fresh?

If you are pitching a whole pack of US-05 into one gallon you may over pitching quite a bit. I do 2.5 and 3 gallon patches and sometimes I literally pitch half a pack and save the rest for the next beer.

How do you save the rest, and are there any caveats/precautions? I've read some pretty stern language warning against that for.. sanitation? Cell viability?

For my most recent batch I did pitch just half the pack (per the instructions, I'm sure even that is overkill) and tossed the rest in the trash, assuming that saving the dry yeast from an open package was risky.

If you don't mind the extra work from doing starters, you could harvest clean yeast directly from starter. Yeast count wise it is really unnecessary but it will practice you for bigger batch and will allow to pitch awoken yeast ready for war. You could also do a big starter and split in different package with the approximate count needed for your multiple batches.

I would personally just pitch half a pack of dry yeast every batch.

mainbutter said:

How do you save the rest, and are there any caveats/precautions? I've read some pretty stern language warning against that for.. sanitation? Cell viability?

For my most recent batch I did pitch just half the pack (per the instructions, I'm sure even that is overkill) and tossed the rest in the trash, assuming that saving the dry yeast from an open package was risky.

Click to expand...

Its a foil pack, I just fold the end over and put a tiny bit of sticky tape on it. when I pitch the other half I just cut a new hole at the other end.

mainbutter said:

So what's the deal with washing yeast? Is this something I should consider with the slurry from hoppy beers, as I understand some hops inevitably make it into the trub? I'm probably getting close to that 8% mark I read about being dangerous for some yeasts for some of the batches I'll make in the next few months as well.. are those both types of batches I should just ditch the cake and start fresh?

Click to expand...

If you go the route that they take in the link I posted earlier:
Collect from low to moderately hoppy beers. You could get some hop sludge going from one batch to another. I doubt that would be a huge issue, but why not just avoid it.
8% is a little high to collect from. Better to collect from the low gravity low ABV brews like Scottish 60/-, Bitter, etc. If you know you're brewing something to collect yeast from be sure to aerate well and consider adding some yeast nutrient.