Top Cropping ?

[Moley]

A bit of help please folks but try to keep it simple and remember I'm just a winemaker who does a bit of brewing.

Until now I've only been using packet yeasts like S-04 and Nottingham, I was never going to use liquid yeasts until I had proved to myself that I could harvest and carry them over to a later brew, and I'm also playing at the moment with bottle cropping because I like the idea of drinking someone else's beer and kidnapping their yeasties for the price of a bit of DME.

I've got some captured Wye Valley yeasties which are currently working on their second task for me and I wanted to save some more for later. They aren't particularly fast but they do seem to do a nice job, and they produce a good head of meringue while they are working.


I've just broken away from typing to take an SG reading and I think this is now a no-go, but I'll carry on for future reference. Tastes excellent though.


Top Cropping seems to be used as a description of how yeasts work, and also as a method of harvesting. How do you do it? Is it simply a case of skimming the froth into a jar, popping it in the fridge and waiting for it to settle?

I did some googling and found this page which says you should do a “dirt skim” around day 2 (which I didn't) and harvest a “middle skim”, which I have probably left too late. It also says to harvest from low gravity, lightly hopped brews. Mine was OG 1.056, currently at 1.018 (slowing down but not yet finished) and I aimed for 50 IBU. Can I still harvest from the slurry or should I forget this and train some more?

 

[leedsbrew]

It depends in how much krausen is left M. Im not usually bother if I have only just missed high krausen. The last time I cropped wlp300 it was just starting to recede and still work a treat.

Also the pitching from low gravity lightly hopped wort issue! Yes I think there are sensible reasons why the above is a good idea. I also think that maybe it has become a case if 'Internet Law'. You can have flavour and colour transference when using the yeast next time, but a quick wash with cooled boiled water is all I've ever done and not noticed anything.
I think it's more important that the yeast are as healthy as possible when you re pitch, over where they came from.

In short I'd go for it.

 

[evanvine]

An advantage of "double dropping" after 24/36 hours of the "madness", is that you get a very clean yeast head reformed, ideal for skimming off!

 

[luckyeddie]

An advantage of "double dropping" after 24/36 hours of the "madness", is that you get a very clean yeast head reformed, ideal for skimming off!

Totally agree with this. The last couple of brews with hyper-aggressive Belgian yeasts have followed this sort of timetable...

Brew Sunday lunchtime, double-drop Monday night, top-crop Tuesday or Wednesday night.

 

[Swazi]

I've been doing this recently and it has worked a treat. I just skim off a couple of laddles of froth from the top a couple of days into ferment (high krausen) and whack into a starter for the following weekend. My methods are a bit reckless (no scientific basis/reason) and are based purely on what I've heard or stumbled across combined with my own disregard for detail.
Tomorrow I'll be doing the 3rd generation of a Belgian yeast I cropped off a friends brew.
When a brew fails, I'll look for answers.
:drunk:

 

[unclepumble]

I've been doing this recently and it has worked a treat. I just skim off a couple of laddles of froth from the top a couple of days into ferment (high krausen) and whack into a starter for the following weekend. My methods are a bit reckless (no scientific basis/reason) and are based purely on what I've heard or stumbled across combined with my own disregard for detail.
Tomorrow I'll be doing the 3rd generation of a Belgian yeast I cropped off a friends brew.
When a brew fails, I'll look for answers.
:drunk:

If you have a good top fermentying yeast such as burton ale or a yorkshire strain its easy to do, skim of the crud 24hrs into ferment, then skim a good load off 48 is hours in, and repitch as soon as you can, if your brewing every week you can keep a strain going forever in theory, you may get mutation due to your process but it may be for the good of the beer, it may be for the bad, only time will tell, and its a lot easier than people think, if you need to save it put it in a jar in the fridge with an airlock on preferably, so CO2 pressure does not build up, and try to repitch within 10 days at the most.

UP

 

[Swazi]

If you have a good top fermentying yeast such as burton ale or a yorkshire strain its easy to do, skim of the crud 24hrs into ferment, then skim a good load off 48 is hours in, and repitch as soon as you can, if your brewing every week you can keep a strain going forever in theory, you may get mutation due to your process but it may be for the good of the beer, it may be for the bad, only time will tell, and its a lot easier than people think, if you need to save it put it in a jar in the fridge with an airlock on preferably, so CO2 pressure does not build up, and try to repitch within 10 days at the most.

Now that's how I should be doing it, and will be for my next run of beers. Cheers UP

 

[Moley]

if you need to save it put it in a jar in the fridge with an airlock on preferably, so CO2 pressure does not build up, and try to repitch within 10 days at the most.

Thanks UP, but unfortunately that was the bit I needed.

 

[unclepumble]

It will last longer in the fridge Moley, it just wont be as fresh and viable, therefore will not perform as well and will eventually need stepping up with a DME starter.

This method also works best with weaker beers up to say 1055og above that and your giving the yeast a fair old work out, they get a bit knackard and start to give unexpected results.


UP

 

[unclepumble]

This link is very informative and useful, if you intend to store yeast for a while. it will work for top cropped yeast too just miss the swill round the bucket part, just skim on day 2-3 wash and store as per the info in the link.

Yeast wash and store Tutorial

UP