8
votes
Accepted
Will reused yeast change beer taste?
we can get away with re-using yeast, because Mutation isn't instantaneous, it take multiple generations to change a whole batches properties. Also bigger brewers use a "mother culture" to grow more ...
- 1,769
7
votes
Storing mason jars of wort, for yeast starters, at room temperature
Without pressure canning, unfermented wort doesn't have a low enough pH to be shelf stable.
From The Maltose Falcons website:
The process is almost identical to the one that you or your family may ...
- 566
6
votes
Accepted
What does a gravity reading really mean?
Specific gravity measures density, which is mass/volume. If you measured the total mass of your system (3000g + 300g) you would have gotten 3300 grams, but the volume is not 3000 ml because you added ...
- 344
6
votes
Production of yeast
Almost certainly the starter yeast is yeast slurry that's been stored frozen in liquid nitrogen. Interestingly, one of the most common methods is to store it inside sealed-off portions of plastic ...
- 6,417
5
votes
Accepted
Why does Northern Brewer's Fast Pitch Canned Wort not require any boiling?
Malt extract does not need to be boiled to make beer. It is perfectly possible to make beer using extract and cold water although it s a little easier if you dissolve the extract in boiling water ...
- 5,631
5
votes
Storing mason jars of wort, for yeast starters, at room temperature
Sanitation is not sterilization. You might find a couple jars out of a batch last longer than others. But the only way to be sure is to buy a pressure canner. They are relatively cheap and can be ...
- 36.2k
4
votes
Accepted
My first yeast starter with a stir plate, possibly a disaster
Smack packs contain yeast nutrients, and sugars nothing magical. Its just a mini starter in a bag for proofing yeast for direct pitching. Don't need it at all If doing your own starter. If you do all ...
- 18.5k
4
votes
Accepted
Should a yeast starter be kept in the dark?
According to Beer Advocate,
This is when the beer has been exposed to ultraviolet light for a period of time. Hop-derived molecules, called isohumulones, are basically ripped apart.
So unless you'...
- 1,152
4
votes
What's the best method of storing yeast for 4 to 6 months in the refrigerator?
Just do it
Nothing you described is needed or beneficial with modern liquid yeast packages. For example Weast's Activator:
The Activator™ package was designed with superior UV light- and oxygen-...
- 3,718
4
votes
Alternative to stir plate for yeast starter (and erlenmeyer flask)
I use a 750 ml bottle, sanitised aluminium foil and a rubber band. Keep aerated by stirring it gently, occasionally during the first 12h; I stir every 6th hour or so. After 18-48h I use it or ...
- 711
3
votes
Accepted
Risks of pitching a high gravity starter?
Just cold crash the starter, decant the beer off and pitch the yeast slurry.
The main function of a starter is to grow yeast to a proper cell count for your batch. It's actually pretty hard to over ...
- 18.5k
3
votes
Accepted
Starter wort volume = BEFORE or AFTER 10-15 minute boil
Yes, starter calculators are a post boil volume.
Your boil off depends on what you're boiling in (surface area mainly) and how hot you boil it.
Do a test to see how much your vessel and burner ...
- 18.5k
3
votes
Should a yeast starter be kept in the dark?
Really depends if you use hops or not. I always put a few pellets in for thier antimictobial properties.
And it depends when and how you pitch your starters.
Light + hops would be bad If your ...
- 18.5k
3
votes
Is these yeast starter calculation correct?
Yes, it roughly lines up using my preferred calculator if I use the stir-plate aeration options (the "C.White" option has 124 bn cells, "Kai" has 95 bn cells).
I'll note that the Brewer's Friend ...
- 10.1k
3
votes
Accepted
Simulating a yeast starter for fine tuning a stir plate
I haven't noticed any difference in the performance of my home-built stir plate between water and wort/yeast with one exception. I often make two-stage starters and refrigerate the flask between ...
3
votes
Cell growth factors in different types of yeast starter
If you're comfortable doing the math yourself you could use some bioreactor equations to model the yeast growth.
I would start with the assumption that growth is limited by initial population, ...
- 328
3
votes
Accepted
Really fast attenuation with starter. Is this to be expected
Yes it's totally possible. But I would expect a lower OG than you estimate. 1.071 is possible to drop out that quick but not very likely.
Take a hydrometer AND refractometer reading on the finished ...
- 18.5k
3
votes
Accepted
Why is a yeast starter necessary? How is it different than standard fermentation?
The point of a starter is to obtain a higher and healthier yeast count before you pitch into the wort. This is accomplished because the 100g of DME/Liter create enough sugar for the yeast to reproduce ...
- 560
2
votes
Is these yeast starter calculation correct?
That is a small batch 2.43 gallons.
I too show a yeast viability at 56%
Your starter volume of 300ml seems low. That is more of a proofing volume.
My calculator shows 107bil cell growth if you use ...
- 18.5k
2
votes
Accepted
Is yeast cell count a constant function of starter size?
No, it is not true. The "yield factor" of yeast is a function of both the starter volume and the inoculation rate.
- 10.1k
2
votes
How long should I expect to wait before seeing activity in my yeast starter?
Have you taken a gravity reading? I've had starters that have very little apparent activity that are fermenting right along. It can be tricky to take a gravity sample for a low-volume starter, but ...
- 10.1k
2
votes
Unwanted yeast flavor last 2 brews (using starter)
First thing, its not generally recommended or needed to make starters when using the dried yeast that you listed. That being said its not likely to super hurt you either.
Its likely a combination of ...
- 36.2k
2
votes
Starter wort volume = BEFORE or AFTER 10-15 minute boil
I don't know your calculator. No one here knows unless you will link to it. So we cannot tell what it's developers had in mind.
That said, you want about 1.040 OG / 10 Blg after boil. If that means ...
- 3,718
2
votes
Accepted
Are starter sizes meant to be actual volumes or container sizes?
When a starter volume is referenced it's the volume of wort the yeast is allowed to grown in. Post boil volume etc. And should have a SG of 1.040
We can't tell you how much a proper pitch is in your ...
- 18.5k
2
votes
Minimal airlock activity
Airlock activity is not the be-all end-all. You could have a bad seal on a bucket or on the airlock grommet itself. Give it a little time (3-4 days) then check the gravity. Gravity movement is really ...
- 1,035
2
votes
Risks of pitching a high gravity starter?
Assuming a 5 gallon batch, this over-sized starter will contribute roughly 10% of the volume of your beer. So any changes it makes to the flavor will likely be small and difficult to detect in even ...
- 933
2
votes
Storing mason jars of wort, for yeast starters, at room temperature
Yeah, unless you actually pressure seal those bad boys, I wouldn't risk it. My rule of thumb is to weigh out the possible benefits and down falls of taking a shortcut. The upside could be saving a ...
- 21
2
votes
Used Wrong Yeast.... Final Gravity Too High
One can pitch dry powdered yeast directly into a brew. It often works well but sometimes not. In my entire brewing career(?!?) I have never used a yeast nutrient(!?!). Some do, some don't.
I usually ...
- 5,631
2
votes
Accepted
Used Wrong Yeast.... Final Gravity Too High
I strongly advise against yeast nutrients, unless you are sure that this addition will not be sensed in finished beer even if yeast will fall to eat it. Once I had a batch less than optimal due to ...
- 3,718
2
votes
What's the minimum amount of active dry yeast to start a ferment?
Spray dried yeast is what the spherical nodules are composed of. Brewers yeast has lost the ability to form spores.
Yeast population do grow rapidly in the log phase of yeast growth. That is usually ...
- 5,631
Only top scored, non community-wiki answers of a minimum length are eligible