Tell me why I need a refractometer

[The_Professor]

I went with the refractometer because I didn't want to "waste" beer every time I took a reading.

But that is actually part two. Part one is that I didn't take any sort of gravity readings at all for at least a year after I started brewing. I actually got pretty good at checking the wort a few days after pitching it and seeing it was becoming cloudy, then after one and two weeks it became clearer. That would be shot glass samples from a Mr. Beer keg. I had one batch that did not become cloudy and stayed sweet for a week and I knew there was something wrong and was able to get the batch fermenting because of my visual and taste check. So not only "why do I need a refractometer" but also "why do I need a hydrometer"? In my case I decided I wanted to have something more concrete than my visual and taste check.

So on one brew I may do nothing more than check the reading post boil. On another I may check the reading during mashing to decide on the mash time. I may do a pre boil check and a post boil check. I can check anytime I want with a few drops of wort.

Now let's be clear. A refractometer is not a hydrometer and a hydrometer is not a refractometer. You can't take a hydrometer out to a vineyard, randomly select some sample grapes and check their sugar content. Any "gravity reading" from a refractometer is a calculation. That calculation is from the Brix reading of the refractometer. My refractometer is not digital but I get the Brix from marked lines. 25% of a point is about as well as I can tell. This usually puts my OG really close to what it is supposed to be. My FG is often lower than brewing software predicts. But that includes a rounded off Brix reading with a calculation to account with the effect of alcohol on the later reading. Well, in the end -- I have only used a refractometer to take measurements, never owned a hydrometer. I can get an OG and tell if my beer has or has not fermented a bit more reliably than a visual and taste test.

Now why does Kealia need a refractometer? I would suggest a new brewer use either a refractometer or hydrometer to better tell what is going on with their beer and past that I'm not sure there's a reason for both.

[Foothiller]

It's true that you don't "need" a refractometer, but I find mine so useful that I have not used my hydrometer at all for my last several batches. The yield from grains varies, and the refractometer tells me whether I will need adjustments like adding DME. When sparging, it confirms that my gravity stays as high as desired. It does those without waiting for a hydrometer sample to cool, since by that time any adjustments could be too late. Then it's just my habit, but I like to monitor the progress of fermentation for the first few days, and the refractometer lets me do that without wasting beer and risking getting oxygen into the fermenter. As for accuracy, I checked both for several batches and concluded that their measurements are close enough that I don't worry about the difference.

[FedoraDave]

I have not spent the money yet because all those gravity readings really don't matter to me. If I miss, then I miss, I still drink the beer when it's done. It means that it just has a little less alcohol, no biggie for me.

I'm the same way. I take an OG reading just before I pitch, and usually (though not always) toward the end of the fermentation period. But since I let all my batches go three weeks before bottling/kegging, I've gotten lazy and just figured they're done, and at or near the proper ABV.

As far as a hydrometer sample "wasting" the beer, I sanitize the sample tube and hydrometer for the post-boil reading, so I can return it to the carboy. In fact, I use it to triple-rinse the container of yeast, so there's less yeast left behind. And when I check the FG, I don't take multiple readings on consecutive days (again, three weeks is plenty of time). I take the one reading, and then I drink it, because it gives me a sense of how the beer is going to be once it's ready for consumption. Numbers can tell you a lot, but ultimately, I'm drinking my beer, not measuring it, so my tongue actually tells me more than my hydrometer.

[ScrewyBrewer]

I drink my final gravity hydrometer samples too, it's really just uncarbonated beer. The original gravity samples, though really flavorful, are just too sweet to drink and those 4 ounces eventually get dumped.

[Kealia]

Thanks for all the comments. I've decided that I'm happy with the way I do things now and won't be changing. Like many of you, I take gravity post boil and post fermentation and I think that's going to be the way I keep it. I don't want to start to get neurotic about my process, I want to keep it easy and relaxed and there's no NEED for me to buy one.

I think I just needed something to occupy my thoughts yesterday - long week.

Cheers.

[mashani]

Honestly, for me I guess it would really come down to how much I decided to care about what my FG actually is, or just that my FG is stable. If you aren't really worried about what your actual ABV is because of funky calculations, then a refractometer is still going to let you know that your fermentation is done or not, right, because it's going to measure the same for 3 days, funky calculations or not.

I think I could live with that if I decided to.

[Pudge]

Short answer.... you don't.

If you brew smaller batches, you might. For a 5 gallon brew, a couple of hydro samples simply isn't that much and I drink both of those anyway

No real need for 3 samples. I would take both preboil and post boil samples when I first started brewing. I haven't done a preboil sample in years. No need really once you get used to your process. Most homebrewers have a decent idea of what efficiency and boil off rates they get. It doesn't need to be super precise and any adjustments can be made starting with the next batch. I think most homebrewers can tell when their beer is finished. A post fermentation sample is normally just to gather the numbers.

[FedoraDave]

Thanks for all the comments. I've decided that I'm happy with the way I do things now and won't be changing. Like many of you, I take gravity post boil and post fermentation and I think that's going to be the way I keep it. I don't want to start to get neurotic about my process, I want to keep it easy and relaxed and there's no NEED for me to buy one.

I think I just needed something to occupy my thoughts yesterday - long week.

Cheers.

Brewer's Choice, Bro. Brewer's Choice. I won't look askance at anyone's process, if it's what gives them satisfaction. Some guys love the numbers, monitor their mash pH, etc., etc. Me, I figure I'm brewing beer; not sending a rocket to the moon. Could I do better if I engineered my water profile, or got micro-measurements on my grain mill? Maybe, but I'm making good beer that I really like, and I'm formulating recipes that make this hobby fun for me.

Po-tay-to/po-tah-to.

[Beer-lord]

I'm beating an old horse with an old opinion.
http://brulosophy.com/2014/09/08/refrac ... -worth-it/

Me loves the Brulosopher!

[philm00x]

The refractometer I have has automatic temperature compensation, so you don't have to let the sample cool down completely to get a good reading pre-and post-boil. I had broken my hydrometer a couple months ago and my LHBS wasn't open so I used the Google machine to figure out if I could use my refractometer to accurately calculate FG. Turns out Brewer's Friend has a refractometer adjustment tool to help with that, so I haven't replaced my hydrometer. Alcohol in solution refracts light so adjustment needs to be made to calculate FG for fermenting/finished beer. But because it only uses a few drops, I keep more beer in the bucket, which means more beer in bottles/keg. It is good practice to check calibration regularly with distilled water, but like JJ said, it usually is spot on since the first time I used it.