Why Measure OG?

[mng8r]

Just curious, but if you're brewing an extract kit and not concerned with calculating the alcohol %, is there a reason to measure OG?

I've measured it on some of my batches, but always wondered why I did because if it was off the kit's target, I'm not sure exactly what I'd do about it.

Thanks,
Ron

 

[oneandahalfshepherds]

Just curious, but if you're brewing an extract kit and not concerned with calculating the alcohol %, is there a reason to measure OG?

I've measured it on some of my batches, but always wondered why I did because if it was off the kit's target, I'm not sure exactly what I'd do about it.

Thanks,
Ron

If you OG is off you can either add DME if low or add more top off water if OG is too high. Measuring OG helps make repeatable beers and getting repeatable results out of the equipment you brew with.

 

[chickypad]

If it's extract you can pretty much just go with the recipe's listed OG if your volumes are on. In fact, that may be more accurate than trying to measure the OG if topping off with water. You really have to stir well if you're going to do that, and even then it's easy to get a false reading.

 

[AZBeerNut]

Just curious, but if you're brewing an extract kit and not concerned with calculating the alcohol %, is there a reason to measure OG?

Mostly, man... just get used to the practice for when you move beyond kits (which you should do at your earliest possible convenience). By measuring your OG, you can make all sorts of adjustments as desired... adjust the OG in the first place... learn the ABV and what you might want to change next time... figure out how well your yeast performed and what you might do differently... etc...

 

[chickypad]

Just so the OP is not confused, I'm not advocating that you avoid measuring your FG. The FG listed in a recipe is only an estimate, you need to actually measure in order to determine if fermentation is done, calculate ABV, etc. What I am talking about is that with extract batches (either a kit or your own recipe) if you have the correct volume there is no need to measure OG. You are adding a known amount of sugar to a known amount of water, there is really no way to miss the gravity significantly. In fact, as I mentioned, it can actually be difficult to get an accurate measurement of OG when topping off with water. There are threads all the time on here about that - people think they missed their OG by a lot and want to add a bunch of DME but actually they just didn't mix well.

This is all in contrast to partial mash or all grain batches, where you don't know how much sugar you have in your wort because you don't know your efficiency until you measure. On those batches it's crucial to actually measure OG.

 

[Homercidal]

There is nothing "wrong" with not checking OG with extract kits. The better option would be to take the measurement and then adjust if the gravity is too high or too low. If you just don't want to make adjustments (And if you followed the instructions on volumes correctly you shouldn't need to), you aren't going to make poison or anything.

If everything went correctly your OG should be on target and so will your FG and ABV. The FG is more likely to be off, and with it the ABV. The cause is due to variations in yeast health and handling and fermentation conditions. If they are relatively in line with good practices, it shouldn't be off by too much.

Cooling the wort to take an OG was kind of a pain for me, so I bought a refractometer. It is still worth doing IMO even if you brew extract. It's good practice for when you brew AG in the future (if you are considering doing that) when variations in recipes, ingredients, mashing methods, etc. all have an impact on the OG.

So no, it's not terribly important for extract brewing.

 

[ProfessorWoland]

Just curious, but if you're brewing an extract kit and not concerned with calculating the alcohol %, is there a reason to measure OG?

I've measured it on some of my batches, but always wondered why I did because if it was off the kit's target, I'm not sure exactly what I'd do about it.

Thanks,
Ron

If I'm doing a kit I've done before and haven't added anything I don't take an OG.

I am a n00b though so I could be doing it all wrong!

 

[mng8r]

When I brew the kits, I typically make sure I get every last drop of LME and as much DME as possible out of the packaging. I usually start with about 6 gallons of water which ends up boiling down to less than 4.5 gallons of wort. I then top up the cooled wort to the 5 gallon mark on the primary bucket. So, I would think that my volumes are pretty close each time.

I guess part of this also has to do with how far off the target OG a person would have to be to really notice it in the final product. The most recent kit I brewed is the NB Caribou Slobber with a target OG of 1.052. If a person was able to get all the DME and LME in the mixture it would be interesting to know how far off, either over or under, you'd have to be with the volume of water to significantly change the OG.

The first few batches I did a couple of years ago, I tried measuring with the hydrometer, but it seemed to not stay centered, so I wasn't sure how accurate my readings were. Then I figured that measuring would really only confirm if I followed the instructions properly since I didn't know enough to correct any readings. After that, I stopped measuring, but before I start a new batch, I always wonder if I should buy a refractometer to do the measurements. Recently, I've spent the money on being able to boil a larger amount, oxygenate the wort (Williams kit), trying to better control fermentation temps (Craigslist mini-fridge, built a STC1000 temp controller, etc) and yeast starter/stir plate. I guess next on my list will be a refractometer.

Ron

 

[ballsy]

What everyone said here...on full extract there is no "need" to do it b/c you aren't extracting fermentable sugars from grain (it's all in the extract). But I still do it b/c it's good practice, and it's habit b/c I do PM as well. Eventually you will go to PM (and maybe AG) and then it's good idea b/c pending efficiency of your mash, you may need to substitute some extra fermentables in form of DME or LME to nail your expected OG.