Anyone backing this?

[ryanshelton]

https://www.kickstarter.com/projects/17 ... ref=1qk7ar

[simon12]

No, but very interesting thanks for sharing.

[Berk]

I don't see how it can be accurate on a plastic bucket, surely it needs to be on a completely sealed container to work?

[m_rawdin]

I saw this a couple of weeks ago and wondered how accurate it would be and also if any home brewers would even be interested in using one? I certainly wouldn't buy one but I'm sure some people would?

[aamcle]

an answer looking for a question.


aamcle

[vacant]

If you want to know how much CO2 is lost then measuring the weight of the bucket on quality scales will be extremely accurate.

Fermentation produces equal masses of CO2 and alcohol.

example:
23 ltr of 5% ABV contains 1.15 ltr alcohol (23 x 5 / 100). And 1.15 ltr alcohol would weigh 908g (1150cc x 0.7893).

Measuring a drop of around a 1 Kg even if cheapo scales are accurate to only 10g then the ABV would be somewhere between 4.95 and 5.05%.

You could certainly plot measurable weight changes every few hours during the early days.

[Manngold]

I saw it on Instagram from Brewd and Co. Looks interesting, but not worth the price tag for me.

[simon12]

If you want to know how much CO2 is lost then measuring the weight of the bucket on quality scales will be extremely accurate.

Fermentation produces equal masses of CO2 and alcohol.

example:
23 ltr of 5% ABV contains 1.15 ltr alcohol (23 x 5 / 100). And 1.15 ltr alcohol would weigh 908g (1150g x 0.7893).

Measuring a drop of around a 1 Kg even if cheapo scales are accurate to only 10g then the ABV would be somewhere between 4.95 and 5.05%.

You could certainly plot measurable weight changes every few hours during the early days.

Just to check I understand this, are you are saying 23l of wort weighs X amount say 23Kg for this example and after fermentation had lost 908g that would mean its 5%? And this device calculates the same thing by measuring the CO2 lost in volume by counting bubbles and just works the calculation on volume not weight? Using either of these methods would you need to and/or be able to calculate the CO2 weight/volume still dissolved or would this be minimal?

[vacant]

Just to check I understand this, are you are saying 23l of wort weighs X amount say 23Kg for this example and after fermentation had lost 908g that would mean its 5%? And this device calculates the same thing by measuring the CO2 lost in volume by counting bubbles and just works the calculation on volume not weight? Using either of these methods would you need to and/or be able to calculate the CO2 weight/volume still dissolved or would this be minimal?

That's pretty much it. Working with weights means using the densities if you want % ABV (as "ABW alcohol by weight" isn't what we're used to).

My beer weight is 23 Kg and final gravity is 1.012 I have volume of 22.7 ltr (23/1.012)
CO2 weight loss is 908g = alcohol with a density of 0.7893 = alcohol volume of 1150cc (not "g" as in my post! I'll edit that) = 1.15 ltr
1.15/22.7= 5%

Once fermentation is over, I think CO2 held in flat beer in minimal as one Kg of CO2 at standard temperature and pressure occupies 500 ltr!

https://answers.yahoo.com/question/inde ... 938AAAdg0C

[PhilB]

Hi Vacant

While you're correcting things, I think you need to make another slight adjustment ...

Fermentation produces equal masses of CO2 and alcohol.

... fermentation produces the same numbers of moles of alcohol and CO2 ... but a mole of CO2 will weigh 44g, while a mole of ethanol will weigh 46g

Cheers, PhilB

[Fil]

theres a speidle product that does the same, also an adafruit sponsord/hosted diy hack with an arduino doing the same, as an indicator of progress it has a few more flaws than the ispindle and tilt options, as it relies on a sealed fv that you dont open up for a look see or sample draw both of which would cock up its info..

if your looking for a neat automatic gravity readout i would go ispindle and brewpi/brewpi-less
https://github.com/universam1/iSpindel

typical cant find the links for the product n project mentioned but did find this 1 http://www.housedillon.com/?p=1388
als aquarium keepers have an interest in counting bubbles

[vacant]

Hi Vacant

While you're correcting things, I think you need to make another slight adjustment ...

Fermentation produces equal masses of CO2 and alcohol.

... fermentation produces the same numbers of moles of alcohol and CO2 ... but a mole of CO2 will weigh 44g, while a mole of ethanol will weigh 46g

Cheers, PhilB

Good point. When I looked at the chemistry a few years back it was to work out what volume I needed into the fermenter to end up with a known volume into bottles - so I started including a one litre finger-in-the-air loss over fermentation as well as trub loss to calculate a "brew length into the bottle".

But I'm not alone in this approximation - from the kickstarter site "Since the fermentation process generates equal amount of CO2 and ethanol". But worse, they're measuring volume with no mention of correcting this back to STP as far as I can see in the extended faq pdf

[McMullan]

So the assumption being made for these bubble counters is the yeast are in fermentation mode? How do we know when fermentation has actually become the dominant metabolic process in the yeast population? Very difficult to predict. Also, CO2 is odourless, but what gets purged from fermenting wort isn't odourless, so presumably it isn't pure CO2. Dissolved (aqueous) CO2 levels vary quite a lot too, depending on wort clarity/suspended particles. The idea of monitoring a reduction in mass is probably a better surrogate, but how accurate is it? Assumptions remain. And, as you say, Vacant, you'd need some pretty expensive high resolution scales. I think I'll stick with hydrometer samples, which are a better assessment of what's actually going on in an FV, not just for gravity measurements.

[orlando]

FAQ

[Jim]

I suppose for someone with money they don't know what to do with and a love of gadgets it's step forward.