Low starting gravity

Hello, I've just brewed an english pub ale (extract) from the recipe section. The recipe showed it should have about 1.035 - 1.040 OG, mine came out as 1.028. I did a full boil, but I did convert from LME to DME. It called for 3.3 lbs of LME and 1 lb of DME, I used 3 lbs 10.2 oz of DME instead. I'm sure it will come out tasting fine anyway, just trying to understand better - any tips on what could cause the low gravity? Is my conversion off?

Thanks!
Rob

Your conversion is a little low, but not by enough to hit that low of a gravity.. Is it a 5 gallon batch? When I plug your numbers into Beer Calculus I get a S.G. of 1.033 for a 5 gallon batch. Sounds to me like you may have over done it on the water?

It's a pretty common issue for ANYONE topping off with water in the fermenter (and that includes partial mashes, extract or all grain revcipes) to have an error in reading the OG...In fact, it is actually nearly impossible to mix the wort and the top off water in a way to get an accurate OG reading...

Brewers get a low reading if they get more of the top off water than the wort, conversely they get a higher number if they grabbed more of the extract than the top off water in their sample.

When I am doing an extract with grain recipe I make sure to stir for a minimum of 5 minutes (whipping up a froth to aerate as well) before I draw a grav sample and pitch my yeast....It really is an effort to integrate the wort with the top off water...This is a fairly common new brewer issue we get on here...unless you under or over topped off or the final volume for the kit was 5 gallons and you topped off to 5.5, then the issue, sorry to say, is "operator error"

If your target volume was correct, then it will be fine.

More than likely your true OG is really what it's supposed to be. And it will mix itself fine during fermentation.

Revvy, hit the nail on the head with this one. I ran into this same problem with my first batch because I forgot to stir up the wort prior to taking the reading. Stirred up my second batch and that I brewed last week and all was well.

I did a 6.5 gallon boil, which left me with just about 5 by the time I was done - no topping off. This is why I was puzzled. It is a new hydrometer, perhaps it is off. Thanks for the advice everyone!

Rob

Test your hydrometer in pure water at the temperature it is calibrated for. The reading should be 1.000

Also, what temperature was the wort in your tested sample earlier? You may need to adjust your reading if the sample temperature was different than the hydrometer's calibrated temp.

On a related note, I just bottled my very first brew this weekend, but the OG was pretty low compared to what the kit said. This was definitely my fault, but I'm not sure what I should have done differently.

I used two 2.5 gallon containers of spring water, one for the boil and one to top off. When I had everything in and pitched, I was just barely over 4 gallons from boiling losses, so I added more water to bring it back up to 5.

Should I have not added more and left it at whatever volume it ended at? Should I have tried to boil at a slightly lower temp?