Is A Refractometer More Accurate Than A Hydrometer?
One might think that a refractometer is the same as a hydrometer. However, they remain to be two different tools used in beerbrewing and winemaking and it’s important to know their differences. No worries, I’m here to teach you all about it.
Is a Refractometer More Accurate Than a Hydrometer? Well, neither is more “accurate” than the other, they function very differently. A refractometer measures the amount of sugar in your solution via “refraction” of light, when it passes through the wort sample. On the other hand, a hydrometer is used to measure the Specific Gravity of your wine or beer.
You might think these are tools used for the same purpose, and because of that, that one is more accurate than the other. However, that is not the case. Let’s analyze the differences in depth, shall we?
Why Do You Need a Hydrometer or Refractometer?
As mentioned earlier these are two very different tools and perform their tasks in two different ways. However, both of these are needed in order to measure certain aspects of your home brewing solutions, which is essential to achieve your desired results.
When homebrewing, the substance dissolved that will contribute to the Specific Gravity is sugar - derived from malt extract, mash, or both. In the case of wine, there are also different options for sugar-derived extracts.
The number of sugars dissolved in the wort will then be expressed in Specific Gravity, Brix, or degrees Plato. Most homebrewers go by Specific Gravity, measured with a hydrometer, Brix, conversely, is the dominant scale on refractometers.
Then again, there can be exceptions, some hydrometers will display more scales and so will refractometers. But right now, we’ll focus on these two main readings.
But, why would you need any of these two tools?
Primarily to resolve the gravity of the wort or beer you’re working on. These readings should be taken several times a day throughout a specific period of time.
- Pre-Boil - After the mash process, you need to find out the volume and gravity going into the boiling part of the process. This will express how efficient the mash really was. Tip: In order to achieve an accurate reading, make sure the wort is well-stirred.
- Post-Boil - Right after the boil, it is essential that you conduct another reading, just before the fermentation starts. This reading is called your “Original Gravity” (OG) and will be used alongside your “Final Gravity” (FG) for calculations. The latter calculates your final ABV on your beer. For winemakers, this reading is important to know the volume you’re working with before you start fermentation.
- Before the fermentation ends. For winemaking, you should be taking readings every day in order to find out how the fermentation is going and if you need to make corrections. You can even take another reading after the fermentation process has terminated to ensure that the gravity did not shift. This way, you are sure you reached the Final Gravity.
Tip: Make sure you record every reading in your brewing log or any smartphone app that you may have downloaded. If you plan on making more batches, these readings will help you create accuracy in your recipes and perfect your craft! This hard data needs to be contemplated in order to achieve the best tasting wines and beers.
What is a Refractometer?
A refractometer is a brewing tool used to measure the sugar amount in a solution. It works via the refraction of light when it passes through the wort sample.
This device is to be held by the eyepiece up to your eye and facing directly at a light source. You will see a blue and white display, what the gravity of the wort is, expressed in Brix (most of the time).
You can convert Brix to specific gravity, but this will require an extra step.
Tip: Make sure you recalibrate your refractometer before each use, they tend to be a bit finicky. To calibrate the refractometer, use plain water and use the calibration knob to reset the visual to zero.
Refractometers are a great help during brew day. You only need a couple of drops to take an accurate reading. This makes it all much more efficient and quicker.
Refractometer Pros & Cons
- You only need a few drops of your solution for each reading. This helps not to minimize the wort every time you take readings.
- You don’t need to conduct temperature correction due to the small amount of wort you need to take the reading.
- Refractometers are quite fancy and once you get the hang of it.
- You need to calibrate the tool before each reading for accuracy.
- Measures in Brix or Plato. In order to know the Standard Gravity, you will need to do some conversion. You can find online converters, though.
What is a Hydrometer?
Hydrometers are an inexpensive and simple tool for the homebrewer. It is a crucial element to have.
Its only task is to meticulously measure the much-needed SG (Specific Gravity) of the wort or beer. You can do this by having the hydrometer float within a narrow cylinder full of wort, easy!
When you grab a hydrometer, you will notice a scale printer inside of it. It will float lower or higher depending on the test jar of the Specific Gravity of the beer or wort. Find the reading on the scale, measured by looking at where the top of the liquid meets the hydrometer, this is your SG.
Hydrometers are pretty simple to use. Let’s take a look at some of the pros and cons.
Hydrometer Pros & Cons
- Easy to use.
- No need for calibration.
- For temperature correction, you can get a thermo-hydrometer model.
- Inexpensive and high-quality.
- It requires a larger sample size compared to a refractometer. For this, it might be best to purchase a hydrometer with a narrower test jar.
- It is fragile. Choose a sturdy, high-quality hydrometer. There are ones that come with a soft bumper to help prevent damage and breakage.
- With fermentation, these high temperatures may affect the reading, due to carbonation.
- You can calibrate your hydrometer by using a temperature correction calculator in case you need to compensate for an inaccurate reading.
The Final Verdict: Refractometers VS. Hydrometers - Which is More Accurate?
This is completely on the hands of each brewer to decide, depending on the pros and cons each tool may have and which works best with your brewing process.
Tip: If you’re a new brewer, it might be best to get a durable, high-quality hydrometer to start off. It is simpler to use; you won’t need to calibrate it and you can easily read the SG.
Here are more tips in order to help you choose the best tool for your homebrewing process.
- Try both a refractometer and a hydrometer. Maybe, just maybe, reading about these two devices won’t help as much as it would to actually use them.
- If you’re someone who really doesn’t feel comfortable using large amounts of the wart for measurement, a refractometer is a great solution. Then again, you do need to learn how to accurately re-calibrate it before each use. This depends on your own preferences.
- Hydrometers’ downside is the size of the sample you need for an accurate reading. It might be best that you get a hydrometer with a narrow test jar, this will help minimize loss.
- Any samples taken before or after the boil CAN be put back to the boil. In the end, you won’t be really losing much of the wort during these stages.
- For any of these two tools, you will need to take care of the sanitation when sample drawing. It is essential that you sanitize either a hydrometer or refractometer before the reading, as well as any elements used to collect the samples.
- It is NOT recommended to return hydrometer samples into the fermenter.
- As mentioned earlier, for amateur homebrewers, it’s best to start with a good quality hydrometer kit. Not only will you get a great price, but the learning process is much simpler.
2 Essential Tips on Choosing a Hydrometer for New Brewers
- Don’t get the cheapest hydrometer out there. Save yourself the bad experience. You can prevent ugly leaks and bad test jars.
- The cheap glass on inexpensive hydrometers can crack and break VERY easily.
Whether you decide to use a hydrometer or a refractometer, it’s important to know that neither is more “accurate” than the other, these are different tools.
Your decision will solely depend on your preference as a brewer and your unique brewing process. In my opinion, it is best to try both of these tools before you make a final decision.
Nevertheless, if you’re in doubt and in need of a quick solution or you are just starting out, I do think that hydrometers are much more simple to use. These will not only get the job done but will also provide an accurate reading. All in all, good luck, brewers!