Opening bottle for hydrometer?

[Vjuga]

Hello!

Im going to make my very first batch of cider.
Ive read some articles and a lot of times it says to check the total solids with the hydrometer.
Is it okay to open the bottle and get some cider out to check this? Or is it a risk of contamination and/or getting too much oxygen?

Thank you in advance for the reply

 

[hotbeer]

I don't wish to sound rude or snobby, but most of us here only make beer. The cider subforum is a little further down the listing when at the Homepage.

We don't use a hydrometer to check solids. It's used to determine the approximate sugar content of our wort and beer. Comparisons of the specific gravity reading from the time just before it began fermenting to when it completed fermenting allows us to estimate the ABV of our beer.

I'd think that similar for cider, but since I've never made it, I don't know for certain if there are other considerations one does with SG readings for cider.

There are a few members that do make both beer and cider. If you are patient they might show up and respond.

 

[DBhomebrew]

With regards to a hydrometer, there is no difference between beer, cider, mead, whatever.

Oxidation is less of a concern with cider than beer, but you do want to minimize it. Opening the fermenter for a moment, no big deal. Sloshing the liquid about is to be avoided. If (as you ask in another thread) you transfer to a bowl, clean your jug, and transfer the cider back to the original jug, you'll be introducing much more oxygen than during a sample extraction.

With a hydrometer, depending on the tool and its cylinder, you could easily use a good sized portion of your batch if you're making ing 4 or so liters. A refractometer can be used for the same purposes and only requires a few drops. Some will warn you that a refractometer is not suitable once fermentation has started. Best and must-do practices apply for any tool.

Measuring gravity before and after fermentation is how you get ABV. Useful, but not necessary. Measuring gravity at the end of fermentation twice with a few days between and getting the same reading is how you know fermentation is complete. Very important information if you plan on bottling.

 

[Vjuga]

I overlooked the “beer” part thanks for letting me know!

Thanks a lot for the info it’s really helpful. Exited to try it out!

 

[Graham H]

Congrats for joining the science/religion of cider-making!

I’ll second what @DBhomebrew stated about SG readings—when and how they are used, and how they are taken. I make 1 gal batches of cider (apple juice is too expensive for 5 gal experiments, for me) and don’t want to keep stealing ~80mL for every hydrometer sample. I also know that a refractometer isn’t as accurate with quite a bit of effort figuring out my specific conversion factor.
I use my hydrometer for my original gravity reading (Using sanitized equipment, I don’t have to worry about any splashing/aeration at the beginning—in fact, aeration at this point is beneficial).
At the three week point, I take a baseline refractometer reading, coating me a few drop of cider. Every week after that, I take another refractometer reading. Each time the process is the same: sanitize all equipment and the outside of the fermenter, open the fermenter and extract a small sample, close the fermenter, take my reading.
Once I get two identical refractometer readings a week apart, I know that fermentation has stopped. My SG readings by refractometer are significantly different than a hydrometer reading would be at this point, but I’m not using the refractometer to determine an accurate SG—I’m only using it to verify that the SG reading is stable.

Once fermentation is done, I usually rack to a secondary vessel and bulk age for a few months. This is optional, with pros and cons on either side.

Just before bottling/kegging, I’ll pull my second and final hydrometer sample. I use it to determine the FG and ABV. (This also helps me determine how much backsweetening is needed, if any.) Even if you don’t care about ABV, it’s a good idea to record OG and FG. This can help you fine tune your process and work towards repeatability.

 

[Vjuga]

Okay thanks for all the info!

So in the whole process (if you want to rack and back carbonate it ect) its quite some times you have too check with the hydrometer.

I have bought a hydrometer, no refractormeter. It is not so easy to get such a large portion sample out without mixing the inside, right? Do you guys use a large pipet or something like that to get your samples out?
If mixing the cider is not too much of a problem it is also possible to throw back the sample portion in the jug I guess? (ofc with sterilised hydrometer and cylinder)

So much too think about

My very first batch is in the jug now! So I have some time before I need to get a sample

-Eva

 

[IslandLizard]

I overlooked the “beer” part thanks for letting me know!

Your thread has been moved to our Cider forum.
We've also left a "redirect" (link) in the forum you originally posted to. That link will last for a few days.

-- Moderator

 

[Vjuga]

Oh, I’ve just now learned about a beer thief so that makes sampling a lot easier!

 

[Graham H]

Mixing the cider isn’t necessarily bad—just don’t do it on purpose and don’t splash/slosh any oxygen into it via accidental aeration.

I use a small pipet (3mL?) for refractometer samples. I’ve got a 100mL syringe with a short tube to take my hydrometer samples (I usually need about 80-100mL to float my hydrometer, but it’s depends on the diameter of your graduated cylinder).

 

[IslandLizard]

Oh, I’ve just now learned about a beer thief so that makes sampling a lot easier!

"Beer/wine thieves" can be handy, yes.

Or instead, use a "suck siphon." A skinny, 2' (60cm) of hose. It can be snaked through the airlock hole, for minimum disturbance.
Train yourself first on this method, using a bucket or container with water.

 

[Rish]

Oh, I’ve just now learned about a beer thief so that makes sampling a lot easier!

You could also just put a sanitized hydrometer in the jug and leave it until it's done. You don't lose any cider that way.

 

[IslandLizard]

You could also just put a sanitized hydrometer in the jug and leave it until it's done. You don't lose any cider that way.

Depends on the size of the headspace, though... You'd need to leave enough space so it doesn't top out.
With most beginners headspaces are typically either huge or virtually non-existent.

 

[Raptor99]

I usually use a refractometer. I like being able to test using only a few drops.

I also know that a refractometer isn’t as accurate with quite a bit of effort figuring out my specific conversion factor.

It's very easy to do the conversion with a calculator like this: Homebrew Refractometer Calculator When using a refractometer, always record the Brix reading, not the SG scale. If you have recorded the original Brix, then any time you take a measurement you can find the current SG using the calculator.

Once I get two identical refractometer readings a week apart, I know that fermentation has stopped.

This works even without using the calculator to find the current SG. But if it is possible that the fermentation is stuck rather than complete, you might still want to find the SG so that you know how much sugar is left.

If mixing the cider is not too much of a problem it is also possible to throw back the sample portion in the jug I guess?

If you take a sample for testing with the hydrometer, there is no reason not to pour it back into the jug as long as all of your equipment has been sanitized.

 

[Graham H]

It's very easy to do the conversion with a calculator like this: Homebrew Refractometer Calculator When using a refractometer, always record the Brix reading, not the SG scale. If you have recorded the original Brix, then any time you take a measurement you can find the current SG using the calculator.

Thanks, I’ll give this a try on my next cider—do side-by-side comparisons of hydrometer->SG and refractometer->Brix->SG.

 

[Chalkyt]

In my experience taking a hydrometer and brix reading before fermentation then monitoring "on the way down" with a refractometer and on-line calculator gives you a good idea of what is going on without having to take large samples.

As well as a regular hydrometer I have a finishing hydrometer (0.990 to 1.020) with big graduations for checking the FG close to bottling time (I sometimes bottle around 1.010 and pasteurise at 2 volumes of CO2 for a slightly sweet carbonated cider, i.e. finish at about SG 1.006 for 10g/L sugar or around 1/2 teaspoon per glass). I use a sanitised "turkey baster" to extract hydrometer samples.

Generally, the hydrometer vs refractometer/calculator difference is within 2 gravity points, mostly because the refractometer scale is small and if the cider isn't perfectly clear the "blue line" can be a bit fuzzy.