What is Reverse Osmosis and Should I use It?

Sep 1, 2023 | About Maple Syrup, DIY Maple Syrup, Our Company, Products and Customers

Reverse osmosis is something that has become ubiquitous in the maple syrup industry. But what is reverse osmosis (or “RO” for short) and should you use one in your hobby maple syrup operation? Read on to find out!

What is Reverse Osmosis?

Simply stated, reverse osmosis is a system that separates water molecules from other substances found in liquids. Reverse osmosis systems can be found in many household water purification systems, in municipal water and wastewater purification systems and in desalination systems. In these examples, water is put through reverse osmosis to remove toxins and unwanted particulates from water so that it can be safe for use.

Reverse osmosis is also used in the food industry to consolidate liquids like fruit juice, to extract whey protein from milk and concentrate milk, and to concentrate maple sap. In these examples, a reverse osmosis system removes water from liquids that contain yummy and nutritous things like sugars, vitamins and minerals so that those yummy things can eventually be sold as value-added food commodities like frozen fruit juice concentrate, evaporated milk, whey protein powder and maple syrup, cream candy and sugar!

Anyone who has ever made maple syrup in any context knows that it takes time and energy to do so. For professional maple syrup makers, time and energy are synonymous with money! As early as 1946, maple syrup producers began using reverse osmosis to decrease the amount of time and energy that went into making maple syrup, thus saving on labor and fuel costs.  USDA testing in the 1960s and 70s was eventually followed by widespread adoption of reverse osmois in the commercial market for maple syrup, which is where we are today.

Typically, basic reverse osmosis units for maple remove half of the water from maple sap. Maple sap is about 2% water (also called 2 brix) when it comes out of the tree, and needs to be 67% – 69% sugar (or 67-69 brix) to be considered sellable maple syrup. When half of the water is taken away from sap with 2% sugar, it becomes concentrated sap with 4% sugar in it. A second pass through a basic reverse osmosis system can make that 4% sugar solution an 8% solution! While that is still far away from the 68% or so percent it needs to be to be considered syrup, one pass through RO cuts your time and energy needs in half, while two passes allow you to make the same amount of maple syrup in 1/4 the amount of time and with 1/4 of the energy. Not bad!

Should I use Reverse Osmosis in my DIY Maple Syrup Operation?

The advantages of reverse osmosis to the professional maple syrup maker are obvoius. That the cost of acquiring, running and maintaining reverse osmosis units is more than offsett by savings in labor and energy is demonstrated by the widespread use of such systems in the industry. But what is reverse osmosis to a hobbyist? Should you use one?

The simple answer is that it’s entirely up to you! Some people are not going to want to complicate their maple syrup hobby by purchasing a plug-in appliance. And that’s ok!

Others are going to worry about the quality of syrup that results from using reverse osmosis. Our take on that is that while there are people who claim that syrup made using reverse osmosis isn’t as tasty as syrup made without it, we are skeptical. (After all, there are also people who say they can taste the difference between syrup made with wood, oil or electricity. We think that’s dubious.)

On balance, we think reverse osmosis is an exciting addition to a maple syrup hobby because it has the potential to remove one of the biggest obstacles to making maple syrup in the first place – time! There are hobby sized reverse osmosis systems on the market, and one pass through one of them cuts boiling time in half!

Reverse osmosis can also make the most of the hobby sized evaporator or pan you’ve invested in by allowing you to double the number of taps you have without making an evaporator upgrade. In the context of the products we carry, purchasing our Sugar Cube Z.B. means you can comfortably go from a 50 tap to a 100 tap operation with the Sapling Evaporator rather than upgrading to the Mini-Sportman Evaparoator Kit. That’s a savings of $4,561 even before you figure in the cost of erecting or buying a sugar house!

One final benefit that our reverse osmosis system – the Sugar Cube Z.B.– offers is that it kills yeast and bacteria in sap so that it can be stored longer between boils. If you are the kind of hobbiest that can’t boil every single weekend, or wants to take a vacation in March, you might consider the Sugar Cube Z.B. as a way to have your cake and eat it too!

A Sugar Cube ZB reverse osmosis system


How to Tap a Maple Tree

How to Collect Maple Sap

How to Store Maple Sap

How to Make Maple Syrup

How to Filter Homemade Maple Syrup

How to Store Your Homemade Maple Syrup

How to Make Maple Cream

How to Make Maple Candy

How to Make Maple Sugar

Sign Up for Our Newsletter