ABV has gone backwards?!?

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jack.mack

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Hi everyone new brewer here!

So I made a few 1 gallon ginger beer brews that came out amazing, I just boiled grated ginger, lemon juice, sugar and water on the stove, let it cool and threw it in a 1 gallon carboy, with the grated ginger in the carboy. After two weeks the ABV had gone from 1.060 to 1.016. I strained the ginger out during racking and bottling stage. ( I also did batched without the ginger in the carboy but found it stronger tasting left in for fermentation )

Now I have an 11Litre glass carboy, I have attempted to make multiple brews but each time I try the hydrometer keeps giving weird readings, in my latest attempt I removed the lemon juice as I read it can throw the PH levels. The brew started at 1.070 and after a week of fermenting really well and the airlock bubbling about 2 seconds apart its reading 1.076.

How can I possibly be getting a higher reading after a week of fermenting?
Its doing my head in, I am making it the exact same ratio in the 4.5L brew as I am in the 11L but my hydrometer is throwing me off.

Hope someone can help clear this up for me.

Thanks Heaps
Jack
 

Northern_Brewer

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Have you calibrated the hydrometer?

Are you spinning the hydrometer each time - it helps give more consistent readings?

Are you correcting the hydrometer reading for temperature ?

 

RM-MN

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Bubbles of CO2 can stick to the hydrometer making it float higher thus giving off readings. Give the hydrometer a quick spin to dislodge the bubbles and read it soon after so more bubbles don't have time to stick.
 

hout17

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If you are using a digital hydrometer (which it sounds like you might be) it can get material on it during fermentation as well as getting bumped around. I've had my hydrometer read higher for a few days before dropping off especially if there is a lot of krausen.

Use an analog hydrometer to get your starting and final gravities and use the digital hydrometer to let you know when fermentation is finished.

If you are using an analog hydrometer then go with the advice above.
 

marc1

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Hi everyone new brewer here!

So I made a few 1 gallon ginger beer brews that came out amazing, I just boiled grated ginger, lemon juice, sugar and water on the stove, let it cool and threw it in a 1 gallon carboy, with the grated ginger in the carboy. After two weeks the ABV had gone from 1.060 to 1.016. I strained the ginger out during racking and bottling stage. ( I also did batched without the ginger in the carboy but found it stronger tasting left in for fermentation )

Now I have an 11Litre glass carboy, I have attempted to make multiple brews but each time I try the hydrometer keeps giving weird readings, in my latest attempt I removed the lemon juice as I read it can throw the PH levels. The brew started at 1.070 and after a week of fermenting really well and the airlock bubbling about 2 seconds apart its reading 1.076.

How can I possibly be getting a higher reading after a week of fermenting?
Its doing my head in, I am making it the exact same ratio in the 4.5L brew as I am in the 11L but my hydrometer is throwing me off.

Hope someone can help clear this up for me.

Thanks Heaps
Jack

What kind of hydrometer are you using? Is it marked for specific gravity?

You say that the ABV went from 1.060 to 1.016, so I want to make sure we're all on the same page with the scale.

Can you describe exactly how you take the measurement?

Are you correcting the reading for the temperature that you are taking the measurement vs. what the hydrometer is calibrated for?
 
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J

jack.mack

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hey guys thanks for the responses, Im using your standard old hydrometer with a scale on the side, I use a turkey baster to fill up a beaker and put the hydrometer in there each time I test. I filled the beaker up with just water and the hydrometer read pretty much on 1.000 so I assume that means its reading correctly? Ill upload a photo after work today of it.

My only thought that could change is if the brew is still above room temperature when I put it in the fermenter for my original reading, could a few degrees warmer throw it off? I wouldn't have thought it would have a huge effect?
 

McMullan

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You could try to degas a sample by pouring it from glass to glass several times, but I can't see CO2 bubbles pushing it up past the OG after it fermented down to 1.016. This might sound like a stupid question, but the hydrometer was floating and not sat on the bottom of the cylinder, right?
 

marc1

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hey guys thanks for the responses, Im using your standard old hydrometer with a scale on the side, I use a turkey baster to fill up a beaker and put the hydrometer in there each time I test. I filled the beaker up with just water and the hydrometer read pretty much on 1.000 so I assume that means its reading correctly? Ill upload a photo after work today of it.

My only thought that could change is if the brew is still above room temperature when I put it in the fermenter for my original reading, could a few degrees warmer throw it off? I wouldn't have thought it would have a huge effect?

Ok, so you're sure the scale is SG?

Warmer wort will read a lower SG, that's why it's important to know what temperature the hydrometer is calibrated at. There are calculations you can do to correct for UT, but if you are far outside the normal range they may not be very accurate. (I wouldn't trust the correction calculations if it's calibrated at 60F and you are measuring at 140F, for example)
 

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