OG on my first 2 brews

[zendon71]

So I recently completed my second brewing process and one thing I have noticed is that my OG's on both of them were a tiny bit low. Any quick ideas on why? they were both made from kits and followed the instructions pretty well both times, but the first batch was supposed to be .050 and it was .044 and the second was supposed to be .040 and it was .036.... Does that generally indicate something I can correct in the process?

 

[myndflyte]

Maybe just watch how much water you are using to top off would be my guess. Being off by 0.004 points isn't that much. Have you tested your hydrometer in plain water and see if it reads 1.000?

 

[mrboz]

So I recently completed my second brewing process and one thing I have noticed is that my OG's on both of them were a tiny bit low. Any quick ideas on why? they were both made from kits and followed the instructions pretty well both times, but the first batch was supposed to be .050 and it was .044 and the second was supposed to be .040 and it was .036.... Does that generally indicate something I can correct in the process?

Are you brewing all grain or extract?

 

[kh54s10]

.004 or .006 difference could be just the margin of error in measuring. I can only read my hydrometer to +/- .002 anyway.

Temperature of the sample and volumes compared to the recipe will make some variation on your measurements.

As said, check your hydrometer. Other than that don't sweat it. IMO that is close enough. You might try to figure out what the cause of error is and try to correct it, or just shrug your shoulders and enjoy the beer.

 

[BlackGoat]

agreed that its not really a big issue but most likely the culprit is that you're diluting it too much with your top of water. Maybe try making a slight adjustment in the amount of water you're using (use less).

 

[mrboz]

+1 that the differences in your OG and targets aren't that significant. If you are brewing AG, this can do with mash efficiency and your sparging techniques. Since you say you are using kits, I'm going to assume extract. As others have said, your water volumes are likely the culprit ... you may not be evaporating as much during your boil (could be due to circumference of your pot, or how hard you are boiling) ... which means your wort is a bit more dilute. Add a bit more DME, boil a bit longer, or don't sweat it.

 

[dkevinb]

Another vote for temperature compensation.

 

[Cyclman]

Having kettles and fermenters marked with volumes is very helpful. There's an easy calculation to determine gravity when adding or boiling off water. For 1.040, take off the one, for 40 gravity units. Multiply by the # of gallons for total gravity units, 40 x 5 gallons = 200. If you boiled that down to 4 gallons, you'd have 200 / 4 = 50, or 1.050 wort. (of course, you may not want to do this, as the hop bitterness would increase with the longer boil).

In addition to knowing exact volumes, temperature is important, but so is thoroughly homogenized wort. Sugars drop, striating the beer, surprisingly quickly. If you take a sample off the top after the beer has sit awhile, the solution is not mixed, and your reading could be low.

All that said, your numbers are super close, so nothing to worry about.