Liquid Yeast Starter Problems

[nabs478]

G'day fella's,

I also read Batz's post on yeast farming, it was the goods.

Firstly I have a bit of a question regarding the gravity of his recipe.

He said 1.5L of water and 1/3 cup of dried malt extract.

I wanted to make 4L, and get it fired up then split it into 8 x 500mL starters.

I bought 500g of dried malt extract, and figure one cup would do, according to his recipe.

Then I quickly did the math... 1 cup looked like about 30-50g or so. So if it were 50g then into 4L would put the gravity at something like 1.013, which is pretty thin, and so I thought I should add about 3 times that amount, which I did. Can anyone tell me exactly how much I should have added, and if Batz's post was right, which I now assume it is, why is such a low gravity beneficial?

Meanwhile, about four hours before the boil I smacked my yeast pack, and by the time of adding it to the 'wort' it had done pretty much nothing, but I figured that would be ok as it said on the pack that you didnt have to wait.

So I added my Wyeast German Ale yeast starter to my 4L of of water plus 3.5 cups of DME, which had boiled then cooled to about 24 degrees C and been given a good shake to aerate it. The temperature on the pack said 21-24 degrees.

This was at about 10pm tuesday night. I set my central heating to 21 degrees and went to bed.

I woke up and it was cold, I had set the temperature but forgot to hit the heat button. It was 15 degrees.

I promptly cranked on the heater and set it to 21 Degrees.

By the evening nothing had happened still.

So I got a little cupboard and chucked it in there with a couple of lights, thinking that maybe if it were a bit warmer it would go, then went to bed.

This morning my little cupboard was at 27 degrees, so I turned the lights off and cranked the heater to 22degrees on the central, which my girlfriend turned off a little later. I got home from uni and it was at 19 degrees.

If I give my mix a bit of a shake it froths up a bit and the gas that escapes from the airlock during my shaking stinks of yesty/fermeting smell, but when I leave it it looks completly dead and the yeast sinks to the bottom.

If you are still reading this, then hopefully you can answer these questions...

1. Am I right in thinking that if the temperature is just outside the range of 21-24 but within 19-27, it should still work but wont work as fast or produce as good beer? But it shouldnt kill the yeast at 27 C should it?

2. Do you need to add anything else other than DME to the wort to get the yeast starter going properly?

3. Is it salvagable? If so what should I do to make it fire up? If not, shall I just ditch it? And thats your stance, what do you think casued the problem?


Thanks in advance for any info.

Pip

 

[blackbock]

Then I quickly did the math... 1 cup looked like about 30-50g or so. So if it were 50g then into 4L would put the gravity at something like 1.013, which is pretty thin, and so I thought I should add about 3 times that amount, which I did. Can anyone tell me exactly how much I should have added, and if Batz's post was right, which I now assume it is, why is such a low gravity beneficial?

The accepted amount is about 100g / L. This should give a gravity of about 1.040. Although you may want a 4L starter, you shouldn't just drop the contents into 4L and hope for the best, you may need to start a bit smaller and divide it as the yeast multiplies.

Meanwhile, about four hours before the boil I smacked my yeast pack, and by the time of adding it to the 'wort' it had done pretty much nothing, but I figured that would be ok as it said on the pack that you didnt have to wait.

You should really have waited until the pack swelled, that is the time when the contents have started to multiply enough to pitch. Having the temperature go up and down is not a good thing either, and you may have made life hard for the yeast. Also, you shouldn't have allowed it to go so high. 27 is too high in any case.

1. Am I right in thinking that if the temperature is just outside the range of 21-24 but within 19-27, it should still work but wont work as fast or produce as good beer? But it shouldnt kill the yeast at 27 C should it?

2. Do you need to add anything else other than DME to the wort to get the yeast starter going properly?

3. Is it salvagable? If so what should I do to make it fire up? If not, shall I just ditch it? And thats your stance, what do you think casued the problem?
Thanks in advance for any info.

It sounds like the yeast has done something, but the conditions have not been ideal. Pour off a small sample of the liquid and smell/taste it. If it smells rotten, it may be. If not, it will probably ferment your beer, but may add some bad flavours. Put it down to experience. Some people use nutrients with the yeast, but that shouldn't be needed with a fresh smack-pack.

 

[petesbrew]

What should a yeast starter smell like?
I made my first ever WLP005 starter over the weekend. Went to pitch it tonight on an IPA, and it smelt and tasted faintly like vinegar.
I chickened out, and grabbed a fresh starter from the fridge, tried that, tasted "better" and just threw that in.
Should I throw in a kit yeast as well, just in case?
Pete

 

[piraterum]

I too have read in several places that 100g of dried malt extract per 1L of water (gravity approx 1040) is suitable for a starter. DME provided it is boiled to to sanitise it, cooled to the temperature you intend to brew at (ie 18-22 deg for ales) then shaken well to aerate it, before adding the yeast provides all you need. It's important the temperature of the smack pack is similar to the temperature of the starter. If you throw a smack pack that's been at 4 degrees straight into a starter that is 24 deg you will shock the yeast and they may die. Take the smack pack out of the fridge and allow it to slowly warm up to room temp before pitching it.

I assume you used tap water? Tap water has the benefit over purified water as it contains trace minerals which assist in yeast growth. It's not really necessary to add any other nutrients.


I agree with blackbock in perhaps it would be better to pitch the smack pack into a smaller starter e.g 500ml. It is much easier to aerate and adjust the temperature with a smaller volume. Once it gets going you can pitch it into a larger volume.

Temperature is important in making a starter, you want to keep it in the optimum growth temperature range as specified on the packet. If it goes too high e.g above 30 deg you risk killing the yeast, if it goes too low e.g. 15 deg the yeast may not die but it may go dormant. You can fire up dormant yeast by slowly rising the temperature to the optimum growth temp and swirling the starter to mix the yeast back into the liquid. Generally if you do all of this and nothing has happened in 3-4 days it is likely you've got a dud :angry:

 

[Stuster]

It's important the temperature of the smack pack is similar to the temperature of the starter. If you throw a smack pack that's been at 4 degrees straight into a starter that is 24 deg you will shock the yeast and they may die. Take the smack pack out of the fridge and allow it to slowly warm up to room temp before pitching it.

There are a few things here. Firstly, shocking yeast is really only a problem with going from warmer to colder. Older materials will say not to go from cold to warmer, but it's not such a big issue really. In fact, mysteriously, pitching straight from the fridge seems to give better results than letting the yeast warm up first. Click here for a bit more info on that. It's not really an issue with the Wyeast packs as you're probably going to smack them first and let them swell to check there is vital yeast in there.

You're better off doing a bigger starter than 500ml if you are using a whole Wyeast pack or a White Labs vial. Starting it with such a small quantity is not really to give you much yeast growth and is hardly worth the risk of contamination (as well as actually having to do it). It'd be best to do a 2L starter if you are planning on using that directly in a standard sized, standard gravity ale. If you are doing a lager, you should do a bigger starter, 4-5L, and then let it ferment out for 4 days or so, then pop it in the fridge for a couple of days or longer and when you want to use it just decant the liquid on top and use the yeast which should have settled at the bottom of your container. One pack should be fine for 4L, but you can step it up to 2L and then 4L. If you are going to pitch the whole lot including the liquid, keep the temperature close to the temp you are going to ferment at as piraterum says.

Anyway, after all that, make sure you reuse the yeast so you don't have to make starters every time.

 

[piraterum]

There are a few things here. Firstly, shocking yeast is really only a problem with going from warmer to colder. Older materials will say not to go from cold to warmer, but it's not such a big issue really. In fact, mysteriously, pitching straight from the fridge seems to give better results than letting the yeast warm up first. Click here for a bit more info on that. It's not really an issue with the Wyeast packs as you're probably going to smack them first and let them swell to check there is vital yeast in there.

Anyway, after all that, make sure you reuse the yeast so you don't have to make starters every time.

Thanks for the link I'm keen to read a little more about cold pitching and how it works!

 

[Mr Bond]

Top link stuster!

Wonder if i should pitch my dry strains straight from the fridge as well( I don't rehydrate as experimentation produced no Quantum leaps)

 

[Darren]

You're better off doing a bigger starter than 500ml if you are using a whole Wyeast pack or a White Labs vial. Starting it with such a small quantity is not really to give you much yeast growth and is hardly worth the risk of contamination (as well as actually having to do it).

Stuster,

I have to disagree with that statement

If you have a fresh smack-pack or vial, I betchya that it is healthier than most (if not all) of HBers 500ml starters. The yeast contained in the packs/vials are designed specifically to ferment 20 litres of wort. If you pitch a fresh one into 500 mls of wort, you have gone backwards.

If you have one that is a couple of months old, then a starter should be employed and appropiately airated.

Anyway, after all that, make sure you reuse the yeast so you don't have to make starters every time.

I agree. Just watch your sanitation

cheers

Darren

 

[mfdes]

If you have a fresh smack-pack or vial, I betchya that it is healthier than most (if not all) of HBers 500ml starters. The yeast contained in the packs/vials are designed specifically to ferment 20 litres of wort. If you pitch a fresh one into 500 mls of wort, you have gone backwards.

I think Wyeast packs (even when fresh, a rare thing by the time they get accross the Pacfic Ocean) are designed to do an adequate job, but you'll find the amount of yeast in them is only enough to mostly prevent other infections from taking over.
If you look at commercial breweries and microbreweries you'll find they use far higher pitching rates which ensure the fermentation gets off to a good start. This is especially important with the cold fermentation temperature of lagers or if your aeration is less than ideal.
Some of the disadvantages of pitching too few yeast cells/L (other than increased infection risk) are increased esters and possibly a higher FG of the finished beer (though the latter usually only in high gravity worts).

There are many references out there that give proper pitching rates. In any case as little as 500mL of starter will usually be far superior to just the contents of the commercial pack. I usually make either 500mL and pitch at high krausen or 2L and pitch only the dregs after the starter is finished fermenting. Adding hops to the starter helps as hops are bacteriostatic (they retard the growth of bacteria). The amount of yeast cells/L when you pitch a Wyeast pack into 500mL of wort are such that they almost invariably get a good enough head start to inhibit bacteria and wild yeasts, and the amount of yeast/L when you pitch a starter into your wort is much larger (orders of magnitude) than the straight packet.

I have never had an infected batch when using starters and I always reuse the yeast cake from the bottom of the fermenter at least once. By comparison I've had 2 infected batches, both using Wyeast (one with Irish Ale and the other with European Ale), both when I did NOT make a starter, but pitched the swollen packet contents straight in.

Hope this helps!

MFS