Filtering Yeast

[Toobly]

To keep this short, I'm wondering if a coffee filter will remove yeast? I'm only looking to remove about 10ml.

Here's the reason why:

I want to weigh a 10ml sample prior to adding yeast and weigh a 10ml sample after primary fermentation. I'm tired of losing a whole beer or two using the hydrometer and don't like the refractometer so I'm trying to find a way to determine specific gravity without using those tools. I would need to filter out the yeast to get an accurate final gravity as the yeast would contribute to a higher weight.

I figured if a 10ml sample weighs 10.46 grams before fermentation and a 10ml sample weighs 10.12 grams after fermentation it would correlate with a 1.046 SG and 1.012 SG.

 

[Yooper]

In short, no. A coffee filter will not remove yeast, which is microscopic.

 

[RedlegEd]

To keep this short, I'm wondering if a coffee filter will remove yeast? I'm only looking to remove about 10ml.

Here's the reason why:

I want to weigh a 10ml sample prior to adding yeast and weigh a 10ml sample after primary fermentation. I'm tired of losing a whole beer or two using the hydrometer and don't like the refractometer so I'm trying to find a way to determine specific gravity without using those tools. I would need to filter out the yeast to get an accurate final gravity as the yeast would contribute to a higher weight.

I figured if a 10ml sample weighs 10.46 grams before fermentation and a 10ml sample weighs 10.12 grams after fermentation it would correlate with a 1.046 SG and 1.012 SG.

Hi. While your idea seems plausible to determine your SG/FG using a 10ml sample, I think it would be hard to execute consistently. The "average" Saccharomyces cerevisiae yeast cell is ~3-6 microns. A really fine coffee filter might be ~5-20 microns, so you can see it'll be crap shoot as to whether you get them all or not. You might want to experiment to see what the real difference actually is from a hydrometer reading vs a non-filtered weighed sample. BTW, how is it you're losing a whole beer per sample? My hydro samples only use 125ml. Maybe your hydro sample tube is too big? Ed


ETA: What Yooper said, in a much more succinct manner than I.

 

[HopHeavy]

I can't be the only one who drinks hydrometer samples... Waste not, want not!

 

[Toobly]

I may be exaggerating the amount I lose. Any loss of beer is a sad thing... Thanks for the help!

 

[sky4meplease]

If your fermenting in buckets you can pop the lid and drop the hydrometer into the bucket to read gravity.
If your in a carboy tie the hydrometer with dental floss and slowly lower it in get your reading and carefully pull it out.
I have never pulled a sample for a gravity reading.

 

[Toobly]

If your fermenting in buckets you can pop the lid and drop the hydrometer into the bucket to read gravity.
If your in a carboy tie the hydrometer with dental floss and slowly lower it in get your reading and carefully pull it out.
I have never pulled a sample for a gravity reading.

I've thought of that too. The scientist in me just wants to try a new approach.