OG Question

[HibsMax]

I brewed an Old Peculiar (sic) clone yesterday. The recipe says that the OG should be between 1096 and 1100. When I measured mine, a few times (while taking temperature into account) was "only" 1082. I followed the recipe exactly (ingredients below) so what could cause such a difference in the actual vs expected OG?

9.9lbs of light malt extract syrup
2lbs brown sugar
3oz molasses
4oz roasted barley
8oz 120L crystal malt
1oz nugget hops
1oz fuggle hops

I used the gravity calculate (TastyBrew, I am sure there are many) and put in all the ingredients and based on 100% efficiency I should be getting 1091. I got 1082. That calculator allows me to mess around with the efficiency so I just punched in 90% and it got me to 1082.

Any comments? Is 90% good? Should I be aiming for higher?

 

[DrJerryrigger]

well if you measurements were a little off and you added a little more water that would account for that. Also you have some grain in there that no one can get 100% out of. So if you got 70% out of the grain (which is a fine amount) that would bring your total efficiency down to about where it was.
So really, it's fine don't worry about it. Seems about right.

It's odd that the recipe expects you to get 100%eff out of the grain too...

 

[HibsMax]

Thanks, Doctor.
You might be right about the volume of water, I believe I have a little more than 5g in my fermenter.

I'll ask the author of the recipe about the apparent expected 100% efficiency. It's possible that when he wrote the recipes he simply used a calculator and plugged in 100%.

I'm not overly worried, just trying to get the process down pat so that, some day, I will be making my own beers and not someone else's.

Thanks, Max

 

[Pezman1]

You are brewing an extract beer from a kit/recipe with 12 oz of steeping/specialty grains. Grain efficiency simply doesn't factor into anything you are doing.

If you use all the fermentables and end up with exactly the right amount of wort specified, you WILL be in the target range of the OG. There is no way not to. In fact, there is no reason at all to even take an OG with an extract kit/recipe, unless you just want to for fun.

So why did your OG differ from the recipe?

If you did a partial boil or had to top off with water, it is hard to get the wort perfectly mixed, and odd gravity readings result.

Maybe you didn't use exactly the right amounts of fermentables : extract left in the jug, brown sugar not firmly packed when measuring, etc.

Maybe you ended up with more wort volume than specified.

Maybe the person who devised this recipe when over on HIS measurements or calculated the OG wrong???

Cheers! Pez.

 

[HibsMax]

You are brewing an extract beer from a kit/recipe with 12 oz of steeping/specialty grains. Grain efficiency simply doesn't factor into anything you are doing.

If you use all the fermentables and end up with exactly the right amount of wort specified, you WILL be in the target range of the OG. There is no way not to. In fact, there is no reason at all to even take an OG with an extract kit/recipe, unless you just want to for fun.

So why did your OG differ from the recipe?

If you did a partial boil or had to top off with water, it is hard to get the wort perfectly mixed, and odd gravity readings result.

Maybe you didn't use exactly the right amounts of fermentables : extract left in the jug, brown sugar not firmly packed when measuring, etc.

Maybe you ended up with more wort volume than specified.

Maybe the person who devised this recipe when over on HIS measurements or calculated the OG wrong???

Cheers! Pez.

Thanks, Pez.

I had a nice long reply written right before the forum crashed earlier. So this reply will be briefer.

I did a partial boil (1.5g) and added that to 3g of cold water. That brought the total volume to just over 5g. I wasn't taking into account the volume of the syrup or sugar so I should probably have added to 2g of cold water and then topped off as necessary. You can always add more water but taking it out after is a real SOB!

The malt syrup came in a plastic bag and I was unable to get all of it out, some stuck to the sides. But I don't think I lost that much out of the 9.9lbs, maybe 1oz at the most. The brown sugar was a 2lb bag so I am confident about that.

It is possible that I didn't mix my wort thoroughly enough before measure the OG. I did give it a good shake-up before pitching though. Next time I will shake, measure OG then pitch.

Anyway, one thing reading these forums has taught me is not to worry so I'm happy just to amble along and learn as much as I can.

- Max

 

[Pezman1]

Very True! Relax and enjoy!


From your reply my money is on the fact that you did a partial boil with top-off. This is often cited for giving some strangely high or low OGs.

I am an extract brewer (thinking of all grain soon) but I brew from kits or recipes and haven't taken an OG in two years.

Pez,

 

[HibsMax]

You are brewing an extract beer from a kit/recipe with 12 oz of steeping/specialty grains. Grain efficiency simply doesn't factor into anything you are doing.

If you use all the fermentables and end up with exactly the right amount of wort specified, you WILL be in the target range of the OG. There is no way not to. In fact, there is no reason at all to even take an OG with an extract kit/recipe, unless you just want to for fun.

So why did your OG differ from the recipe?

If you did a partial boil or had to top off with water, it is hard to get the wort perfectly mixed, and odd gravity readings result.

Maybe you didn't use exactly the right amounts of fermentables : extract left in the jug, brown sugar not firmly packed when measuring, etc.

Maybe you ended up with more wort volume than specified.

Maybe the person who devised this recipe when over on HIS measurements or calculated the OG wrong???

Cheers! Pez.

Me again!

I am in the process of transferring my notes from paper to my website and I got to my Old Peculiar and scratched my head again.

I used the Tasty Brew calculator and when I enter the Light LME, brown sugar and molasses ONLY, I get an OG of 1085. When I measured it it was 1082. Pretty close. When I add the specialty grains that are steeped for 30 miniutes, I get an OG of 1089.

My question is this, when using the calculator to compute the OG, should I include the steeping grains or not? I seem to get a better answer, for this recipe, if I ignore the steeping grains. "better" meaning the OG is closer to the one listed in the recipe.

 

[Pezman1]

Ignore the steeping grains in extract kits as far as computing OG.

Most are higly kilned specialty grains added in small amounts and are designed to impart flavor, body or head retention, not be a main source of fermentable sugars.

You might have to take them into account if you have a recipe with a ridiculous amount of steeping grains, but certainly not with just a pound or less.

At any rate, ALL the numbers you mentioned are good and within the variances for a kit.
Pez.

 

[Calder]

In 5 gallons, 10 lbs of malt syrup will give you 1.072. 2 lbs of brown sugar will take you up to 1.090. The extra molasses will give you less than a point (I added half of the molasses to the malt to get 10 lbs).

Grains: When steeping they are primarily there for flavor and color, but you will extract sugars from many of them; some more than others. If using a calculator, assume 50% efficiency for a rough number. 12 ozs of grain will give you about 14 points, or add about 0.003 to a 5 gallon batch.

Your final gravity should have been around 1.093 if you made exactly 5 gallons. If you made 5.5 gallons, you would have an OG of 1.084.

Fully mixing the syrups in cold water is a source of a lot of incorrect gravity readings.

 

[HibsMax]

Thanks, Guys. I ended up with a little more than 5 gallons and I now know the importance of measuring gravity after mixing the wort VERY well i.e., after I aerate - I didn't do that this time.