Hello,
I've been reading this site and various other resources for a month or so, and I've finally decided to start my first batch. I decided to go with a simple, rum-like mixture, and make a small quantity, just to test things out first. Here's the process I used:
Boiled 250 mL tap water in a metal pot
Added 75g of brown sugar and 25g of molasses (about 125 mL worth together) - they dissolved fine
Added 250 mL cool tap water
Cooled mixture to 75 degrees farenheit using a cold water bath
Added .5 grams of dry bakers yeast that had been dissolved in warm water as per package instructions
I put this into a pyrex erlenmeyer flask with a single hole rubber stopper, and put a trap valve in place on top of it
It is now 8 hours later, and I have yet to see any fermentation. I've double checked my conversion from the larger recipes, and I believe the measurements to be accurate. Does anyone have an idea what may have gone wrong?
Having trouble achieving fermentation
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possum
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possibly the wort(beer) was too hot when you added the yeast ==cooked yeast...Not unless the warm water was way too hot.
some disolved oxygen is needed for yeast to reproduce.
boiled water can be flat... try opening open the container, for 1 min, close up(cover hole with clean thumb) and shake. This helps aerate the wort.
if you do all of this, and still no action...Is your tap water chlorinated?
after 24 hours w/no action, add more yeast.
Is this is a small"starter" ? As in a yeast starter to inoculate a larger batch,
or is it an experimental ferment?
some disolved oxygen is needed for yeast to reproduce.
boiled water can be flat... try opening open the container, for 1 min, close up(cover hole with clean thumb) and shake. This helps aerate the wort.
if you do all of this, and still no action...Is your tap water chlorinated?
after 24 hours w/no action, add more yeast.
Is this is a small"starter" ? As in a yeast starter to inoculate a larger batch,
or is it an experimental ferment?
Hey guys!!! Watch this.... OUCH!
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possum
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- Location: small copper potstill with limestone water
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The Chemist
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Guest
I'd like to thank you both for your help, I've tried a few things on my own, and I seem to be at an intriguing solution. I'll try to cover everything brought up so as to help anyone else who may be in a similar situation.
To first cover the issues raised that don't seem to have been the problem:
The yeast itself was bought immediately before use from a supermarket, and reacts appropriately when simply mixed with water and a little bit of sugar in what the yeast packaging describes as "proofing" (it foams up). This procedure is recommended on the packaging to be carried out at 100 to 110 degrees farenheit. In testing, I do not seem to be able to get the reaction at 90 degrees farenheit, and would assume the same would be true at lower temperatures.
I was using a thermometer in the wort and measured the temperature to be 75 farenheit - everything I've read seems to tell me that this is nowhere near high enough to kill all the yeast.
Next, the issues that may or may not be related to the problem I was having:
When I shake the covered flask with the wort in it, I do seem to get some CO2 production for a few minutes, but I suppose this could simply be air bubbles?
I'm not sure on the issue of chlorination of the tap water - I'll see what I can do in terms of testing it.
Finally, the solution I was able to reach:
I took some yeast that had been through the "proofing" method described above and added it to the wort. It had a thick head of foam on top of a yeast saturated liquid. By this time, it had cooled to room temperature (approx. 78 farenheit). It was a relatively massive 3.5 grams of the base dry yeast (opposed to the 0.5 grams calculated as needed). I added the entire mess, foam and all. Within a few minutes, I was seeing evidence of fermentation.
It is my understanding that a large overpitching of the yeast like this will produce undesirable compounds affecting taste and odor, but we'll just have to see on that.
I would then hypothesize that the brand of yeast I am using ("Fleischmann's Active Dry Yeast") apparently must be somehow activated by temperatures in the range of 100-110 farenheit before being added to the wort. The case may then be that the water I was using to activate the yeast was not hot enough. Alternatively, it may simply take a long time to get around to fermentation with this yeast. I'm not sure what the large excess of yeast did to the reaction. Logically, it should speed up the reaction, as there are more organisms processing the sugar, but hopefully the calculated amount of dry yeast will be able to be tested as viable in a future test, which I'll get around to shortly. What I mean by this is that 0.5g of the dry yeast, once adequately "proofed", will hopefully be able to do the job by itself.
In regards to the purpose of this batch, it is definitely of the experimental nature. I wanted to get a feel for the process on a small scale that could be more easily controlled.
To first cover the issues raised that don't seem to have been the problem:
The yeast itself was bought immediately before use from a supermarket, and reacts appropriately when simply mixed with water and a little bit of sugar in what the yeast packaging describes as "proofing" (it foams up). This procedure is recommended on the packaging to be carried out at 100 to 110 degrees farenheit. In testing, I do not seem to be able to get the reaction at 90 degrees farenheit, and would assume the same would be true at lower temperatures.
I was using a thermometer in the wort and measured the temperature to be 75 farenheit - everything I've read seems to tell me that this is nowhere near high enough to kill all the yeast.
Next, the issues that may or may not be related to the problem I was having:
When I shake the covered flask with the wort in it, I do seem to get some CO2 production for a few minutes, but I suppose this could simply be air bubbles?
I'm not sure on the issue of chlorination of the tap water - I'll see what I can do in terms of testing it.
Finally, the solution I was able to reach:
I took some yeast that had been through the "proofing" method described above and added it to the wort. It had a thick head of foam on top of a yeast saturated liquid. By this time, it had cooled to room temperature (approx. 78 farenheit). It was a relatively massive 3.5 grams of the base dry yeast (opposed to the 0.5 grams calculated as needed). I added the entire mess, foam and all. Within a few minutes, I was seeing evidence of fermentation.
It is my understanding that a large overpitching of the yeast like this will produce undesirable compounds affecting taste and odor, but we'll just have to see on that.
I would then hypothesize that the brand of yeast I am using ("Fleischmann's Active Dry Yeast") apparently must be somehow activated by temperatures in the range of 100-110 farenheit before being added to the wort. The case may then be that the water I was using to activate the yeast was not hot enough. Alternatively, it may simply take a long time to get around to fermentation with this yeast. I'm not sure what the large excess of yeast did to the reaction. Logically, it should speed up the reaction, as there are more organisms processing the sugar, but hopefully the calculated amount of dry yeast will be able to be tested as viable in a future test, which I'll get around to shortly. What I mean by this is that 0.5g of the dry yeast, once adequately "proofed", will hopefully be able to do the job by itself.
In regards to the purpose of this batch, it is definitely of the experimental nature. I wanted to get a feel for the process on a small scale that could be more easily controlled.
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gmccormick
Didn't see The Chemist's reply when I started that 
. My thoughts on the amount of sugar were aimed at a concentration of 0.20 kg/L, meaning that for 500 mL, I want 100g of sugar. Then, I've also read that molasses isn't metabolized completely by the yeast, so I figured I was in safe territory. I'll look at lesser sugar concentrations as well, though, in future batches. Thank you.
. My thoughts on the amount of sugar were aimed at a concentration of 0.20 kg/L, meaning that for 500 mL, I want 100g of sugar. Then, I've also read that molasses isn't metabolized completely by the yeast, so I figured I was in safe territory. I'll look at lesser sugar concentrations as well, though, in future batches. Thank you.-
jbrew9999
You will most likely be sucessful (as long as your sugar concentrations are within range) with your "calculated" future pitchings.
Yeast quantities don't necessarily scale linearly like the other (dead) ingredients. For instance, when doubling or tripleing a batch of bread dough, you don't need to change the amount of yeast at all. In your wort, the yeast you are adding is like a seed colony. It grows and grows and fights for dominance until it has satureated the solution then it continues converting sugar until it runs out. If you don't pitch enough to start with, the whole colony might lose the fight to some other fungus, bacteria, or hostile environment (too much sugar, to much acid, etc).
Yeast quantities don't necessarily scale linearly like the other (dead) ingredients. For instance, when doubling or tripleing a batch of bread dough, you don't need to change the amount of yeast at all. In your wort, the yeast you are adding is like a seed colony. It grows and grows and fights for dominance until it has satureated the solution then it continues converting sugar until it runs out. If you don't pitch enough to start with, the whole colony might lose the fight to some other fungus, bacteria, or hostile environment (too much sugar, to much acid, etc).