This can't be; please recheck my calculations

[phishfood]

Last week I brewed my first "real" allgrain beer, a porter kit from Midwest that was supposed to have a OG of 1.042. The grains were 9 lbs of domestic 2 row, 8 oz Carapils, 12 oz Black Patent, plus I threw in ~about 1 lb of Maris Otter that I have on hand and am trying to use up. I thought that since I am really new at this, I would get low efficiency, and could probably use the extra sugars.

Anyway, from what I read in the online edition of How To Brew by Palmer, a good rule of thumb is to assume .035 points of gravity per lb of 2row per gallon of water. My preboil gravity was 1.042 with 7.5 gals, and if my calculations are correct, that gave me an efficiency of ~90%. I didn't think that I did my formulas properly. Postboil gravity was 1.054 in 5.75 gals.

I now have an APA kit from Midwest in the boilpot, having mashed 9lbs 2 row, 8 oz Carapils, 8 oz Crystal 10L, and with the same ~1lb of Maris Otter added. Preboil gravity was 1. 054 in 6 1/2 gals. Using the same .035 per pound per gal assumption, it seems as though I got around 91% efficiency.

I am not believing that I have things working so well with so little experience and pretty crude equipment, so I was hoping that someone who understood the formulas a little better could rerun the numbers and see what they come up with.

PS: I did check my hydrometer in tapwater, and it read bang on 1.000.

Edit: the directions I got with the kit called for 5 gallon OG in the 1.042-1.046 range for both brews.

 

[whatisitgoodfor]

You don't mention what mashing method you're using. BIAB can frequently hit 80% or better efficiency without any trouble.

Also, using approximate measurements of grain and trying to get an exact OG estimate is impossible. If you want to know exactly what your OG should be, you'll need to start weighing the extra grain you're adding.

 

[phishfood]

Mashing in a cooler with a grain bag, 'cause I haven't had the time to make a manifold. Sparging in the same grain bag, but in my 8 gal pot.

Yes, I know that I need a scale in the worst way. I have found some electronic postal scales on ebay that are supposed to be good down to 1/10th oz for pretty cheap, but SWMBO is rather sensitive to spending on "hobbies" right now.

I understand your point, and agree with you. But I know that my guesstimates of grain weight are pretty close, as I have used a friend's scale to weigh some of the grain for partial mashes before so have a pretty good idea what volume equals what weight. My friend has been out of town for the last couple of weeks, so I couldn't use his scale.

But, assuming I am close, do my numbers work?

 

[Backporchbrewery]

I put your recipe in Promash, and to hit 1.054 @ 5.75gal it says your efficiency is at 74-75%.

 

[SpanishCastleAle]

Here is the TastyBrew online gravity calculator. It's not perfect but works in a pinch.

 

[IrregularPulse]

Entered the second recipe into Beersmith. For a volume of 6.5G at 1054 the efficeinecy came in at 88%.
Move the MO up to 1.5lbs (since you said the 1lb was approximate) and it take it down to 84%, which is still good.

No reason why you couldn't be hitting these numbers. A lot of people have some awesome systems around here. Doesn't mean you can't get great efficiency and make great beer with some buckets and a grain bag! Just means they like building things.

 

[like2brew]

84% sounds pretty damn good to me

 

[SpanishCastleAle]

84% sounds pretty damn good to me

It's good only if the beer tastes good. Every system has a limit and if you push it too far you'll have great efficiency but crappy tasting, harsh, astringent beer. Which is really a total waste and thus 0% efficient.

Not saying this is phishfood's (or anyone else in particular) case just saying that when chasing high efficiency, at some point every system hits a ceiling and going beyond it will reduce beer quality.

 

[phishfood]

Thanks for the answers, everyone. The TastyBrew link was most helpful, particularily when I asked it to show the calculations, and it showed the point potential of the grains. Two of the grains, the 2 row and the Maris Otter, were showing somewhat higher potential than I was giving them credit for, which is why I was getting slightly higher efficiency percentage when I did the math.

This is definitely a learning experience for me, and I get to have fun at the same time. What more can I ask for?

Maybe some really good beer??

SpanishCastleAle, thanks again for the link. If these beers end up so bad that I can't drink them, I'll let you have them.

 

[phishfood]

Just starting to drink the porter, and it is pretty flippin' good. The little bit of APA left in the bottom of the bottling bucket tasted good to, but I will know better in a couple of weeks.

A double IPA that I put together today is already bubbling away, when I have a minute I will run the numbers to see what I got efficiency wise with this one.