Whether a home ice maker or a doctor, you’ve wondered at least once if your homemade ice cubes have been tampered with. After all, it can be cheaper to cut ice than buy it, which is why some people have reported seeing cuts in price rather than purity when purchasing ice cuts with natural mineral salts such as sodium metasilicate (MSM).  

Luckily for home brewers, we know better than most how to tell if the ice cut with MSM or anything other than common salt. Even though it might seem like there are only a couple of different ways of cutting ice at home, there are more. Keep reading to learn about five methods you can use to tell if your homemade ice is being tamed with anything other codeable like sodium metasilicate. 

Smell the Ice 

Some people think that all you need to know to tell if ice cubes are cut with SMS is to smell the ice. That might be true for a doctor or scientist, but for the average home brewer like you and me, this is not the case!  

If you’re smelling the ice, you’re not smelling the salt, and you’re smelling whatever chemical the ice maker used to make the ice. Several compounds can be added to ice that change its smell and taste, most of which smell like chemicals. If you’re smelling chemicals, you can’t be sure your ice is pure. If you’re smelling nothing but the typical smell of plain, un-cut ice, you can be reasonably certain your ice is pure. If you’re not smelling anything, don’t be surprised. This is likely because the ice you’re making isn’t cut with SMS. 

Look for Coloring Agents 

We can see the ice through an ice cube, right? Like in the picture above, right. And if the ice maker isn’t cutting the ice but is colouring it, we’ll see through it. Unfortunately, this isn’t the case. If you’ve peeled back an ice cube to see what the ice is made of, you know that the ice is not coloured.  

While it’s true that colouring agents are used in some ice cuts, it’s also true that many ice makers don’t use any colouring at all. If you’ve noticed your ice is coloured, but the ice cubes still seem to pass the test with the other methods we’ll discuss, you can be reasonably sure your ice is pure. 

Test for Bacteria with an API Test 

If you’re a doctor, you might be able to tell if ice is cut with minerals. But even if you are one, you probably aren’t. This is why there are other methods we can use to test ice for purity.  

An API test is the most accurate way to try ice for bacteria. In this test, the ice is filled with microbes—which means, in this case, we’re talking about bacteria—and then it’s melted down and inspected for any signs of contamination. Several companies offer this service, but the most popular one is probably Chill Guard, which charges around $6 for one ice cube. Ice cut with sodium metasilicate and filled with bacteria will give you a false-positive result. This is why it’s essential to have other methods to rule out the ice being pure. 

Check for Crystal formation and hardness 

Now, this might be the best way to tell if ice is cut with minerals if you’re a doctor or a scientist. If you can determine if the ice is formed by something other than water like this method can, you can be reasonably sure your ice is pure. You can check for crystal formation and hardness by taking the ice out of the freezer and putting it in the refrigerator for a few hours.  

If the ice has formed crystals, it probably wasn’t cut with pure sodium metasilicate. If the ice has begun but isn’t hard, it probably wasn’t cut with pure sodium metasilicate. It’s worth noting that some ice cubes will not form crystals in the freezer, and it’s these impurities that we can use this method to tell apart from impurities in the SMS ice. 

Other Ways to Test Ice for Pureness 

Suppose you want to take your ice testing to another level. In that case, you can try to identify if your ice is cut with magnesium carbonate. Although this method is a bit more complicated, it’s easier than identifying impurities in the MSM, since magnesium carbonate is one of the few minerals commonly used in ice cubes.  

To place magnesium carbonate ice, you’ll need a few things: – Water – A refractometer or hydrometer – A freezer – A freezer thermometer. Fill a glass jar with water, then place the pot in the freezer until it’s frozen. After the water has been completely frozen, please remove it from the freezer and place the jar on a level surface. Next, pour the water from the level surface into a bowl until it’s at least half full, and then place the bowl inside the freezer. Next, immediately check the temperature of the ice, and note the reading. After the ice is completely melted, retake the temperature and note the difference. 


Ice is one of the most common beverages people consume. Still, many home brewers are unaware of the dangers of purchasing ice from a store. Many restaurant ice machines use salt, a cheaper and more dangerous substance. Thankfully, there are several ways you can tell if your ice is cut with sodium metasilicate or other impurities. Make sure to follow these tips to ensure your ice is pure.