Testing gravity increase risk of infection?

[Brew Manchu]

Hi all. A new brewer here, using the coopers micro-brew kit with lager fermenting at the moment. Excuse me if I'm being too cautious here, but does testing gravity daily increase the chance of infection? I tested yesterday (day 4 of brewing) and realized that in order to get liquid into the test tube you need to remove the airlock, which allows air into the fermenter. If I do this everyday until the brew reaches a stable gravity, will I be putting it at greater risk of infection because of the introduced air? I know testing once or twice probably won't increase the risk much, but I'm just paranoid that any more than that will greatly increase the chance of infection.

 

Are there any "tricks of the trade" that I can use to minimize the amount of air that is sucked in the fermenter each time I test?

 

I've really learned a lot from reading all of your previous posts here, so thanks a million!

 

Cheers!

[AndrewC5]

Well the main one i would suggest is to not check everyday, check it when the bubbleing on your air lock slows down around day 4-6.

 

Theres no real tricks to stop the air getting in, because as u take out mass, is must be replaced by something.

 

Also, a little bit of air wont hurt as long as its not dusty or polluted air. When the beer is fermenting strongly, it is more resistant to infection. You only need to wory about it when its starting and finish fermentation.

 

At least you remeber to take out your airlock, every time im testing i hear a bubbling noise and get a surpise to see water running back into my brew [surprised !

[Muddy Waters]

G'day Brew Manchu,

 

As Andrew said there is no worries with air getting in your fermentor it's the dust and particles you need to worry about. Also if you test your gravity too much you wont have much beer left to bottle [tongue]. I usually only check mine 2 or 3 times maximum but I tend to leave my beer in the fermentor for 2 weeks - approx 1 week for fermentation and 1 week to let the beer settle a bit. However, it is better to check the gravity too much than too bottle early.

Are there any "tricks of the trade" that I can use to minimize the amount of air that is sucked in the fermenter each time I test?

 

I used to forget to take out the airlock when I took a sample and have sucked water back in from the airlock many times without a problem. I promised myself when reading your post that I wouldn't mention this as I get a bit repetitive...BUT...What I do now is I don't use an airlock or a lid. I just put a bit of cling wrap over the top, secure it with the o ring from the lid and put a pin prick in it to let the air to escape.

 

Welcome to brewing and welcome to the forum mate [biggrin]

[AndrewC5]

if you test your gravity too much you wont have much beer left to bottles

Ive done this too, haha

[Brew Manchu]

Thanks for the advice fellas. You've put my fears at ease. When taking my first sample, I caught myself just as the fermenter was about to suck in the airlock water. I guess it's a typical newbie mistake! My first gravity reading was yesterday (day 4), which gave a reading of approx 1015. My OG was around 1041, so it appears I have at least a few days to go. But the whole reason I decided to test it at day 4 was that the airlock activity ceased. I know the rule of thumb here is to ignore the airlock, but I figured that because it was bubbling vigorously the first three days that I should test it when it ceased, which was last night. I'll likely let it sit until Sunday and then test it again. Although I quite like tasting the gravity samples [biggrin]!

 

Also I have another question: does anyone know if I can I buy the European Lager Kit at Big W or other retail store? With our bout of coldish nights here in SA, my brew room now has a constant temp of about 16c. I figure this would be perfect for a lager yeast.

 

Thanks again for your help. I have a lot to learn from you guys!

[AndrewC5]

Yeah i really like tasting my own product, its like a child that you produce! ahah

 

I know for a fact woolworths and Kmart stock coopers.

[Muddy Waters]

Yeah you'll be able to get the Euro lager at Big W (and some Woolies - but then some Woolies just have the original series). Big W is generally cheaper than the supermarkets and have a better range than K Mart.

[Slurtis Staggersalot]

speaking of testing SG I racked my batch of Thomas Coopers selection IPA today almost 6 days in the fermenter. I built the batch as recommended on the can and have been fermenting at 20 degrees celcius. I took a reading with the hydrometer I bought today and it was right around 1010 so the hydrometer says it's done.

 

I racked into a glass Carboy and used an airlock that seals well. Guess what, she started bubbling after racking. There was no airlock prior to racking just a lid sealed with cling wrap. I'm thinking I'd like to bottle Sunday but I may leave it for another week to clear....and finish fermenting?

[Muddy Waters]

Airlock activity doesn't mean much Slurtis. Take another reading in a day or 2 and if it is stable then she is done. Can't hurt to then give it a few extra days to settle.

[Slurtis Staggersalot]

Muddy, I know now Ignore the airlock but the thing is I have had good success by paying attention to the airlock and making sure that I've had a very good seal. Basically, if the airlock is stuffed into a glass carboy and it doesn't leak (you can test this with a little soapy water) then it is a good indicator to when the brew is finished. I always like to give it a little time to settle after it's finished anyhow. Honestly after taking my first hydrometer reading tonight, I'm feeling more confident trusting my airlock.

 

I think my above conclusion is due to my inexperience using the hydrometer. I took my sample using my little buddy bottler (I also used it to rack my beer) I noticed that it behaved like a fresh poured beer. The test tube had about 3mm of head and the beer had rising bubbles. I wrote this off as pouring activity, 15 minutes later same thing. I spied about 1010 through the foam but it was probably actually a little lower 09 or 08ish. I've read that bubbles can cause an inaccurate reading, I've also read that sugars can cause an inaccurate reading if you don't run a little beer off before filling the hydrometer (OG).

 

what if I drop my hydrometer directly into my beer and read it that way? I actually have two hydrometers and two glass carboys this could be accurate and fairly easy to read. What I mean is that the hydrometer will be sanitized and become parts of the brew, for the duration of the brew. Good idea or bad idea?

 

Bear with me guys, when I do anything beer making related I also consume beer (The hydrometer reading was during the first beer being consumed)

[Muddy Waters]

If you feel confident in trusting your airlock Slurtis that's up to you but an airlock can still be active after fermentation is complete or be silent at the the height of fermentation. The hydrometer, when used correctly is a scientific indicator as to the density of the liquid. Discard the first bit of liquid you take from the wort as this may contain sediment build up and give inaccurate readings. Then enough liquid to take a reading - give the hydrometer a spin to dislodge any air bubbles. I generally leave my hydrometer on the bench for an hour or so to make sure I am getting more accurate readings (and for the beer to come up to room temp - especially relevant for lagers).

 

I personally wouldn't put the hydrometer in the fermentor as I would worry about infection. Also, you would have no way to dislodge the air bubbles from the hydrometer.

[Luke]

I racked into a glass Carboy and used an airlock that seals well. Guess what' date=' she started bubbling after racking. There was no airlock prior to racking just a lid sealed with cling wrap.[/quote']

 

The bubbling is probably just Co2 coming out of solution.

 

BTW Brew Manchu......Great name! [cool]

 

[Slurtis Staggersalot]

That makes sense Luke in fact it makes perfect sense, the beer in the test tube looked like it was carbonated. I guess I better smarten up and start using my hydrometer more.

[Muddy Waters]

Hydrometers can be helpful things. A mate of mine who never uses one recently left a pilsner he was making for 4 weeks swearing that it was still going because the airlock was still farting. I convinced him to take a reading and the gravity was still at 1042.

 

He kegs so it wouldn't have been a huge problem (other than having a pretty crappy beer) but if he bottled it it could have been interesting[ninja]

[Slurtis Staggersalot]

So, what did your buddy do? My guess would be that if he pitched new yeast it might have fermented... I put another batch of IPA on yesterday and the OG was 1042 I hope it doesn't stay there [biggrin] Thanks Muddy! Your sig is a good reminder.

 

Rule 1: Use your hydrometer Rule 2: Ignore the airlock Rule 3: Ignore the airlock

[Muddy Waters]

He pitched new yeast, but the moral of the story was that he usually would have just assumed it was finished and bottled/kegged.

[PB2]

A mate of mine who never uses one recently left a pilsner he was making for 4 weeks swearing that it was still going because the airlock was still farting. I convinced him to take a reading and the gravity was still at 1042.

He pitched new yeast,

 

[rightful] [rightful] Alert, alert Brewing Police!!

 

Muddy, 4 wks sitting with wild yeast and other bacteria. Hmmm [sideways]

 

 

[Muddy Waters]

[rightful] [rightful] Alert, alert Brewing Police!!

 

Muddy, 4 wks sitting with wild yeast and other bacteria. Hmmm [sideways]

 

 

[annoyed] I hope the brewing police lock him up and throw away the key! I'm more annoyed because he gave me a split of the pilsener yeast he was using and it I suspect it stuffed up my version of the Green Neck Lager I was making at the time. Time will tell - I wish I'd just stuck to my plan and used the Euro lager kit yeast [pinched]

 

[Luke]

Never mind Muddy, you can still use it as snail bait!