In order to be able to get the best refractometer for your purpose, it’s important that you first figure out what they do, how you need to use it and a bunch of other questions. In this article, we’ll walk you through the different things you need to know so you’ll make the right decision.
What is it?
Refractometers are used to give the concentration of a liquid solution by measuring its index of refraction where refraction means the measure of how light bends when it comes from one medium to another. The medium could be from a solid to a liquid (prism to the concentrated solution) or a liquid to another liquid.
Refractometers measure the concentration of a substance in a solution by passing light through the liquid sample and they have a scale where you can read the extent of refraction. Highly concentrated solutions have higher numbers.
A refractometer is preferred over other methods such as hydrometers because it consumes very little sample (few drops) for tests. The devices use refraction as the principle of operation to get their results.
Refractometers, just like circuit breaker charts, have so many uses thus get utilized in many industries such as the food and beverage industry, agricultural, chemical and manufacturing where the properties of the liquids are analysed to give the characteristics needed.
Despite the fact that refractometers work on the same principle there are different types just like Watt generators have, based on the source of power, where they are used and how they are used. The types include;
This type gives readings without using any type of external source of power but natural light. A test subject is first put on the glass prism of the machine and then held by directing it towards a source of light while viewing through the eyepiece. By viewing through the eyepiece one can see two regions, a dark one and a light one, reading the value at the border of the regions gives the current value.
Digital options produce their own light from an inbuilt LED source instead of sunlight or an external light source which illuminates through the sample. An inbuilt computer calculates the refraction index and displays the value on a screen.
These are designed for use in laboratories and are more accurate compared to the other two. They are placed on benches just like microscopes in the labs.
- Brix– The brix scale is used by refractometers that mostly test sucrose concentration in a solution. It is mainly used in the food and beverage industry.
- Salinity– This scale is used to test the levels of sodium chloride concentration in a sample and mostly used when testing in seas and oceans to check their salinity levels.
- Coolant– The coolant scale is mainly used in the automotive industry and checks the effectiveness of ethylene glycol as a coolant and whether the freezing and boiling points have reached to the levels desired.
- Clinical – A lab scale used to determine the specific gravity of urine and serum albumen.
- Specific gravity– Determines liquid density in relation to the density of water
Where is it used?
Where are they used? We often get this question so many times by curious readers and fans but the truth is, just like safety helmets, it is utilized in more industries than you can imagine. For instance, you can exploit it for your domestic purposes or see it being used in industrial or medical setups. They can be used in several fields just like extension cords.
Like many other industries, the agricultural sector is evolving and so are the methods of ensuring that farm animals get top quality care right from birth. Refractometer use has been employed in so many areas of agriculture, similar to amp wire sizes in electricity, some of which we highlight here to ensure that your animals get the services they deserve from you.
|Where it is used|
|Beer and wine brewery||Food and beverage|
|Colostrum wellness||Crop growing|
1. Colostrum wellness
Getting to know the colostrum quality is every farmer’s wish as it possibly determines the probability of the calves getting immunity passed on from their mothers. Calves that get the high-quality colostrum have a higher resistance to diseases as compared to others thus need to check early in their lives for a remedy to be taken as soon as possible if need be.
2. Crop growing
You can use one when your crops are growing to determine their health and nutrients level. High levels of brix readings are an indication of healthy crops. Some crops when they have a higher level of reading serve as an indication of a possible high crop yields and bumper harvest or a crop with a high disease and pest resistance.
Lower readings on the other hand could possibly be an indication of plants that are in trouble probably due to stunted growth. The low readings could be caused by mineral imbalance that leads to growth of weeds or low calcium content in the soil.
The use of this piece of equipment has over time proven to be the easiest way of monitoring plant growth due to the ease of conducting the tests. The small size of it and its ease of operation makes it the preferred way of many farmers to conduct the test at home and get to know the status of the plants.
3. Food and beverage
They are used in the food industry to determine moisture and sugar content in the food being tested. For example, while being used in honey, the moisture content is usually tested to determine the quality of the honey. For industrial honey, it is used to determine the quality of the produced honey to be used as an ingredient in other foodstuffs to ensure that the quality of the food is not compromised.
For your homemade jam or marmalade production you can use one to determine the right quantity of sugar to use for a good taste which could be likened to getting the right length for your extension cord. Unlike commercially produced jams, we often strive to have the right quantities of both fruit and sugar while producing ours at home and we can only achieve this if we check using one whether we have the required ratio.
4. Beer and wine brewery
For the lovers of homemade alcohol, they’re the perfect tool for getting the right percentages by volume of your drink. For effective beer or wine making you first need to have the volume of sugars in your solution that you intend to ferment to produce the alcohol.
With the initial sugar volume, you can monitor alcohol production by getting the volumes later to determine how much sugar has been consumed in the alcohol production process. By getting the difference you can easily determine the alcohol content of your drink.
Handheld options are preferred for these measurements because they are less bulky and easier to use with minimal wastes as compared to other methods such as hydrometers that require a large sample to test similar characteristics.
In the automotive industry
In the automotive industry, they can be used to help lengthen the life cycle of our engines by ensuring that the ratios of the chemicals used to make the engine coolant neither freeze nor boil easily.
When using one, we can easily determine the percentages for either water and glycol to get optimal freezing points depending on our geographical locations. By getting simple ratios such as 50% each we lower the freezing point of distilled water from 32℉ (0℉) to 35℉ (-37℃).
They can also be used to check the charge levels in our battery acids by checking the concentration of the ions in the solutions. Lower hydrogen ions would indicate lower charge in batteries which in turn indicates the need for addition of either battery water or acid.
How does it work?
Refractometers work based on refraction, which is simply how light bends coming from one medium to another for example from the solid glass of the refractometer to the liquid being tested.
Once tested, it determines the refractive index of the liquid solution from which the concentration can be gotten through predetermined values. It is important to note that it is based on facts such as light bends more in highly concentrated solutions. The index mainly depends on composition of the solution and temperature of the solution too.
Refractometer vs hydrometer?
Hydrometers measure the density of liquids based on Archimedes principle, through fluid displacement while refractometers indicate the index of materials from the principle of refraction from which the sugar concentration can be determined. Both are used to test sugar concentration.
When using the hydrometer, you get your results in specific gravity which is the density of your test sample as compared to that of water and refractometers indicate their results in brix. There are calculators that can be used to convert the units from brix to specific gravity which many people are more conversant with.
Refractometers test samples are usually small with just a drop or two taken from the solution using a pipette to give accurate results while for hydrometers the samples required are usually large and need to be taken in another container for the hydrometer to be immersed and give the density.
There is a higher risk of batch contamination when using a hydrometer as compared to a refractometer due to the large volumes of samples needed for results in hydrometers. Some people do not discard their test samples but pour it back in the solution risking the whole batch while others just immerse the hydrometer in the solution.
While the tests taken by both devices are usually affected by temperature, refractometers are less affected due to their sample size, mostly a drop, which can easily cool. If using a hydrometer, you need to adjust the readings based on the temperature of the solution you are working on.
When looking at the cost of both to determine which one you will purchase, the hydrometer is usually the cheaper option. If you are budget constrained it is better to acquire the hydrometer since you will use it for fermentation from the beginning till the end while refractometers are rarely used after fermentation since it loses its precision.
How to use and read one
Before using one, you first need to ensure that it is well calibrated and that it will give you the accurate values as required. Their readings are usually affected with changes in temperature thus there is the need to recalibrate the it to the temperature that you will be using for the reading. However, you might find some models that have Automatic Temperature correction (ATC), acting as an automatic SAE to Metric conversion chart, which gives accurate readings at any temperature by automatic correction.
- To check whether it will give the correct readings first we check using distilled water.
- Pour two drops of distilled water on the glass surface of the refractometer and close the lid.
- Look through the eyepiece pointing the device towards light and read the value at the border of the blue region and white region.
- If the value is not equal to one you need to adjust it to give accurate readings.
- To adjust, use a screwdriver to turn a knob just behind the prism till the reading gets back to 1.
- You can now use it for other readings
How to use one
- After calibration first pour the water and leave the prism to dry to reduce chances of contaminating the solution you intend to test.
- After it has dried, pour about two drops of your solution.
- Close the lid, the lid evenly spreads the liquid throughout the prism.
- Hold it towards a light source to get the readings.
Best brix, digital and portable options
There are thousands of brands around the world the same way we did to best wood chippers, but we have developed a list of top-rated brands that we trust are of good quality from our interactions with them. It is also important to note that they may not have high resale value compared to showers and bathtubs.
Anpro gives you good value for your money and it is a recommended top brand for those who like brewing beer at home. Winemakers and cider makers can also use it to test the quality of their alcohol before it is ready for consumption.
Anpro performs a sugar test giving readings for you to compare sugar content as from when you started brewing till when you find it good enough for consumption. This refractometer requires calibration before use each time for you to get accurate results.
Milwaukee digital salinity refractometer
This is an electronic option with Automatic Temperature Compression (ATC) capabilities (ability to give readings similar to those of room temperature despite the temperature readings) which makes it highly reliable. ATC makes it possible for you to use the machine severally without the need for recalibrating.
While using the Milwaukee digital salinity product, you can easily record the readings because they are highly visible as illuminated by the machine. This digital salinity refractometer also gives the temperature at which the test was conducted.
We highly recommend this option for those with saltwater aquariums at home.
Vee Gee Scientific Handheld Option
A good quality highly portable, budget pack option made with a rubber handle which gives it a sturdy and firm grip while getting the readings. It is easy to calibrate and does not come with an Automatic Temperature Compression mechanism for any temperature that you need to cater for.
However, it offers an acceptable accuracy range usable for our home readings.