What is your term for a frozen ice beverage? Slush (or Slushie, Slushy, Slushee), Icee, Smoothies, Slurpee or Slush Puppie? There are actually some significant differences among these products. However, many of them can be served in a piece of commercial foodservice equipment known as a “granita machine.”
Granita machines are commonly found in convenience stores and concession stands as frozen beverages are key items for both audiences. But granitas are not just for sugary kids drinks. Granita machines are also commonly used for adult alcoholic beverages such as frozen margaritas.
But let’s not get ahead of ourselves. Let’s explore how the restaurant and foodservice industry came to call a frozen beverage machine a “granita machine.”
What is Granita?
Whatever you call it, nearly all frozen beverages owe at least a small debt to something called “granita.” This is often referred to as “Italian Ice” more commonly. Granita shares some common ancestry with sorbet and sherbet. They are all closely related in terms of how they are made. The ingredients and proportions vary.
A traditional granita is composed of sugar, water and any number of flavorings. Its texture is a bit more granular than sorbet. And many granita recipes involve coffee or coffee flavoring.
Food historians trace granita back to ancient Arab, Greek and Roman traditions of chilling drinks with snow and ice. In her book “Pomp and Sustenance:Twenty-Five Centuries of Sicilian Food,” author Mary Taylor Simeti suggests that the invention of granita could have even been an accident.
“The passage from sarbat and water, chilled in a container of ice, to granita was only a question of time, perhaps the chance invention of a housewife distracted by a passing vendor or a crying child.”
What she is implying is that if the sweet wines or juices common of that era were left in ice too long, they became slushy. Thus, granita was born.
Birth of the Granita Machine
In the restaurant and foodservice world, frozen beverage machines are often referred to simply as granitas. They come in many varieties but all generally do same things.
First, let’s clear up a potential misconception about 2 of the most popular frozen beverages. The Icee and the Slurpee from convenience store 7-11 are a bit different than other, similar frozen beverages. These frozen beverages are typically made from carbonated beverages. This complicates things a bit. It means that a pressurized CO2 (carbon dioxide) tank must be used. So the dispensers for these types of beverages are specialized and more difficult to maintain.
But all frozen beverage dispensers share some key features.
The Bowl or Tank
Sometimes referred to as the tank, the place where the frozen mixture is stored is most commonly referred to as a “bowl.” Granitas can come in different sizes. But even that can mean different things. First, is the size of the bowl. You can get bowls as small as about a gallon. But most commercial machines feature larger bowls of 2-4 gallons each.
But granita machines can come with multiple bowls on a single machine. You can have a double or triple bowl granita. Each can hold a different flavor or different beverage. And this is important for buyers of commercial restaurant equipment. Often, you will see a machine listed as holding 4 gallons. But if it is a double bowl granita, that doesn’t mean you get 4 gallons in one bowl and 4 gallons in the second bowl for a total of 8 gallons. Instead, it means that each bowl holds 2 gallons and you have a total of 4 gallons for the entire unit.
An auger is a screw-like piece that pushes or pulls the frozen beverage through its threads as they turn. You might think that its primary purpose is to mix the beverage. However, its true purpose is to keep the semi-frozen liquid moving over the cooling surface. It is a delicate balance. On the one hand, you need the beverage to be enough of a liquid that it can be dispensed. But you also don’t want it to be totally liquid either. It needs to maintain that semi-frozen consistency.
Nor do you want the mixture to be totally frozen. This can be a disaster and has been the end of many a granita machine. If the mixture becomes too solidly frozen, the auger can become stuck. In some models, this can cause damage to the motor that turns the auger. If this happens, the machine may become inoperable.
Vollrath recently introduced a granita that uses a magnetic drive motor for its auger. The magnetic drive prevents damage to the auger or motor in the event of a freeze up.
The Compressor & Cooling Drum Surface
Much like a refrigerator or freezer, a granita contains a compressor. To learn more about compressors in refrigeration, check out our article on the placement of compressors on commercial foodservice equipment. In short, a compressor works to pull heat out rather than put “cold” in. The liquid is dredged over a cooling surface by the auger to keep the beverage in a semi-frozen state. The movement keeps the liquid from freezing solid.
If the compressor fails, the mixture will quickly become just liquid. As we review in the aforementioned article, air flow is key to compressor health. Keeping all the parts clean of dust and insuring adequate air flow is critically important in extending the life of your granita unit.
Nozzles & Spigots
You have to be able to easily serve the frozen beverage from your granita machine. This happens through the serving spigots. These simple devices involve a couple of important parts including the handles and gaskets.
It is important to consider the height of the spigot and the size of the glass or container into which the beverage will be dispensed. If you are using extra tall cups, be sure that you have the clearance under the spigot to accommodate them.
It’s All About the Mix
Making the perfect frozen beverage is all about balance. If your mix is off, you may end up with a drink that is too watery or too frozen. However, with a few simple tips, you can be sure to create the perfect frozen beverage every time.
The first consideration is the sugar content of your mix. If you are not using a commercial, ready-made mix you will want to measure your sugar content very closely. Typically, you want the sugar level of your mix to be around 15% (a range of 13%-17% is acceptable). If you go below this range, your mix may become too frozen. If you go too high on your sugar levels, then your mix may not freeze at all.
To help get the sugar proportions just right, you can use an instrument called a refractometer. Wine makers frequently use refractometers to measure the sugar content of the grapes used to make wine. It can be very helpful in creating custom granita mixes.
The next consideration is alcohol. Alcohol is considered an anti-freeze. Proper balance of alcohol in your mix is critical. When making an alcoholic granita mix, you should only replace about a quarter (1/4) of the water content with alcohol. Using more than that will not allow the mix to freeze properly.
Some mixes contain dairy products such as milk. This requires a little special care and attention. You need to be sure that the unit temperature is set high enough to insure food safety of your milk-based mix.
Cleaning & Maintenance
Like most things in a commercial foodservice environment, a granita machine needs to be cleaned regularly. The beverages dispensed by a granita often contain a lot of sugar. When you combine this with a moist environment you have a good platform for mold.
Many granita models have a cleaning or washing mode. This can be helpful in keeping up with maintenance. Unfortunately, these washing modes are not enough to completely clean your unit. Some amount of manual work will be required to keep the unit properly maintained.
Hopefully, this is obvious, but before you begin a full cleaning, make sure your unit is turned off and unplugged. Always follow the manufacturer’s guidelines for cleaning your granita machine. In general, you want to be sure that you are thoroughly cleaning all the silicone parts. This may include the auger and blades as well as the spigot and all the feeder tubes if present.
The bowl(s) itself are typically removable. Keep in mind that this is the area where the product is stored and must be carefully cleaned to avoid residue that could contaminate the product. Most manufacturers recommend simply washing with warm, soapy water. And of course, be sure to rinse thoroughly.
As we mentioned above, be sure you are cleaning any fans, filters, and coils to remove excess dust. Too much dust can reduce the efficiency of the unit and shorten its lifespan.
Go Pour Yourself a Cold One
Now that you have learned about the basics of a granita machine, you get to the fun part. Go enjoy a tasty frozen beverage.
With some very basic care and maintenance, your granita machine should provide you with years of faithful service.
It’s hard to believe that a humble beverage that may have been invented by accident has spawned a whole new generation of frozen beverage enthusiasts. And now you can tell them about the history of the legendary granita!