Yeast and the OG!!!

[jepputeacher]

I just finished making my second batch of beer - Munton's Irish Stout. I was hoping this time around my OG would be a bit higher, but it turned out to be only 1.035. I added 1.5kg of Munton's light spray malt, and used the yeast that came with the can. I'm curious if the type of yeast (or if the yeast at all) has an impact on the OG? I would really like to get my OG a little higher to make it closer to a 5.5-6% beer. Please help.

Full Details of Brew:
23liters of water (boiled)
1 can muntons irish stout extract
1.5kg of muntons light spray malt
1 package of yeat (came with kit)
Pitched (a lot)
temp at OG measure - 30 degrees C
OG - 1.035

 

[ArcaneXor]

It's not the yeast but the liquid you add with the yeast (remaining starter beer or water) that lowers the OG. But the volume of added water/starter beer is usually so low that it doesn't have a measurable impact. Now if you dump an entire 2-liter starter into a carboy without decanting first, you will see a non-trivial drop in OG.

 

[Suthrncomfrt1884]

Yeast has nothing to do with the gravity of a beer. More sugars=higher gravity. If you want bigger beers, you need to add more extract.

 

[wyzazz]

By my calculations your OG should be about 1.042, how much was in that can of muntons? Did you do a partial boil and use top up water? If that's the case then I'm positive that you didn't mix it enough and got a bad OG reading. Unless you mix it with a drill for about 5 minutes then it's probably not been mixed up enough to be consistent. No need to worry though, the yeast will mix it all up for you during fermentation!

 

[sonetlumiere85]

He was using 6 gallons (23 liters), not 5 gallons

 

[wyzazz]

He was using 6 gallons (23 liters), not 5 gallons

I used 6.07gallons (23 liters) for my calculations, based on the can of extract being 3.3lbs. Not sure how much was in that extract can...

 

[jepputeacher]

Firstly, thank you for the quick replies. You guys are awesome.

Secondly, to answer the first question, I used a 1.5kg can of muntons irish stout (Sorry, I should have mentioned that in the original post).

As to the second question, I boiled the first ten liters of water to sterilize it, then let it cool and put it into the fermentor. Next I boiled thirteen liters of water to sterilize it and then added the can of muntons and stirred it real well. Then added the 1.5kg of muntons light spray malt, and once again stirred it real well. After stirring it, I let it cool to room temperature and then added it to the ten liters of water in the fermentor. While that process was happening, I started my dreid yeast in water for 15 minutes and then added a small amount of water and sugar together, and let sit for 30 minutes until it started acting up. Then I put that in the room temp (30-32 degrees celcius - It's hot in Seoul, Korea) wort. But before adding the yeast I was sure to pitch it real well to get a lot of oxygen inside. About 12 hours later I saw some nice action in my airlock. However my OG seemed a bit low.

Any ideas on how to get my OG higher would be greatly appreciated.

Again, thanks

 

[wyzazz]

If you want to bump your OG up then you need to add more sugars, the simple way do it is just to add a plain pound of table sugar (you could actually do that now if you wanted, just make a syrup out of it with boiled water), the best way to do it would be with some more DME (Spraymalt) in the same fashion. The plain sugar will have a tendency to thin out your beer, whereas the DME will add body and flavor. A quick rule of thumb you can use (I assume you're trying to get a higher ABV) is that 1lb of fermentables will yield 1% of ABV in your final product.

 

[jepputeacher]

Thank you Wyzazz. You have been more than helpful. I think I'll let this one go and chalk it up to a learning experience and will work to improve my next batch which is going to be a Bock beer. If you have any recommendations for that I would be really greatful. If you couldn't already tell, I'm a total noob and this was just my second attempt.

Again thatnks for all of your help.

 

[wyzazz]

No worries, that's what this forum is for!

I'd suggest not trying a Bock (Lager) if you're a noob, there's a lot more involved and most importantly you'll need temp control for the ferment and lagering phases. Do a nice Amber or Brown Ale, Lagers are a bit more advanced. The Bock will require a Lager yeast that will want to ferment in the steady 50's, then you'll have to Lager it in the 30's-40's for a while.

You could do the Bock recipe with a clean neutral Ale yeast, and ferment around 60'ish to get a cleaner taste. It'll be a good beer but not a Bock.

 

[jepputeacher]

Thanks, I'll go back to the brown ale that I brewed on my first attempt. It was pretty tastey, but had a low percentage of alcohol. I'll try to make this one better by adding more sugars. Great Advice, seeing as the average temp here is in between the 70s and 80s. Thanks

 

[wyzazz]

Post the recipe, I'll see if I can give you some advice. You'll want to balance the increased malt with more hops. I'll also suggest that you try and keep your fermentation temps in the mid to upper 60's during active fermentation. Do a search for "Swamp Cooler" for a cheap and easy way to do this. The beer will produce less off flavors if it ferments a bit cooler, after active fermentation is complete (usually 4-5 days) you can start to raise the temps to help keep the yeast awake and active. This will help them to clean up any off flavors that they release.