5

I get usually about 1/4in of sediment towards the end of the fermentation. Does anyone know weather this predominantly dead or live yeast.

I propose to use some and boil it to act as a natural nutrient for a troublesome ginger beer starter bug. They are different yeasts , other is a pale ale yeast. Is this a good idea or should i just buy commercial nutrient.

  • Very well boiled yeast cake can be used as a nutrient for ginger beer SCOBY. The yeast cake can be simmered for several hours to denature any residual enzymes and break down cell structure to release bound nutrients. In what way is the ginger bug troublesome? – barking.pete Jan 17 '18 at 8:49
  • Just not working as expected compared to pix online.Having a discussion with you in another thread so will leave it there. – beerbug Jan 29 '18 at 22:11
3

Yes, yeast cake can be used as a nutrient base with some caveats. It is better if it is not from a very hoppy beer if you want to use it for ginger beer using a SCOBY (the tiny little grains of gel that make a "real ginger beer bug"). Hops are usually tolerated by yeast but the lactobacillius in the ginger beer SCOBY can be inhibited by the hop acids. So adding any amount of hop essence will be detrimental to the bug. In my experience the yeast from a (low hop) lager brew can be strained, rinsed well and decanted a few times. Then the rinsed slurry, which is by then mostly hop free, can be boiled up and used as a nutrient base. Others I have talked to have used a teaspoon tip of "Marmaite" or similar yeast extract product in 2L of water with reasonable results. It might be added that the ginger beer SCOBY seems to work well (over a period of many years) with just ground (or fresh sliced) ginger and sugar. It does take a little while to start and does require oxygen to grow. A thing often forgotten by those using a demi-john with airlock rather than the more traditional muslin covered open vessel. And keep it warmer than cooler. Above 18C is a good place to start - and 20C is often better. Ginger bug tends to "hibernate" below 10C.

2

Yeast-wise, a yeast cake contains enough live cells to process a heavy beer, and some people brew small beers for the entire purpose of getting a yeast cake that they use in heavy beers then.

However, yeast cake contains not only yeast cells, but all sorts of hot/cold break and hop particles that you probably don't want to add to another beer, especially one that is quite different from the one that produced your yeast cake.

As an economical yeast nutrient you can just use dry baking yeast. I always have a rather big can of that at home, as I bake a lot, so occasionally boil a tablespoon of dry baking yeast together with my starter solution.

  • I will split my starter and try that.I was worried that the different type of yeast would contaminate/compete with the beer bug though, should i boil it. – beerbug Jan 16 '18 at 22:14
  • You should boil the baker yeast to kill it so it serves as food for your other yeast – JeanMi Jan 16 '18 at 22:21
  • @beerbug as JeanMi and I said - wherever you take yeast to be used as food, it needs to be boiled. Once it's done, you don't have to worry about "contamination by different yeast". After all it's one species, S.cerevisae, and after boiling it will be just "soup". – Roman Jan 16 '18 at 22:49
0

That yeast sediment is a mix of coagulated proteins, hop byproducts, dead and resting yeast.

It is possible to use this as a base in order to pitch into a new batch, however you will need to wash that sediment in order to get the yeast and make a new starter. Example of instructions here : http://homebrewacademy.com/yeast-washing/

I guess you could also use this washed yeast as a nutrient. Even maybe the complete cake, but be careful with byproducts that could bring off-tastes if you use too much.

  • Thanks, useful link i did not find. I was intending to boil it first though to kill it off and strain out the solids then use the liquor. I notice that nutrients though also have dead yeast hulls in them and wonder if some nutrients are inherintly insoluble. – beerbug Jan 16 '18 at 22:10
  • i was intending to boil the cake to kill it then use the liquor and filter it as liquor to feed for my starter. I notice that yeast nutrients have dead yeast hulls in them, are the hulls needed or will the liquor supply thr required nutrients. – beerbug Jan 16 '18 at 22:56
  • You need your new yeast to feed on the dead yeast, that's why I would first wash the cake and then boil, to make sure you only boil yeast. – JeanMi Jan 17 '18 at 7:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.