Foodservice operators use soft-serve equipment to dispense ice cream, frozen custard, frozen yogurt and sorbet. Key commercial markets for these units include quick-service restaurants, such as frozen treat shops, bakeries and cafés, and full-service restaurants, such as family dining, buffets and casual dining. Schools, colleges and universities, airports and business cafeterias typically have soft-serve equipment in the noncommercial markets.
These systems work by freezing liquid ice cream mix under agitation, then dispensing directly from the freezer into a cone or cup. Soft-serve machines can hold product in this frozen state for long periods until staff dispense portions.
The various types of soft-serve equipment include single flavor; twin twist, or two separate flavors that staff can serve separately or twist together; shake; and combination units that will serve cones and shakes.
Capacities for single-serve soft-serve equipment are about 3.5 gallons, or approximately 100 3.5-ounce servings, per hour. Twist units can produce 15 gallons, or about 425 3.5-ounce servings, per hour per side, for a total of 30 gallons, or 850 3.5-ounce servings, per hour. At the top end, units are available that produce up to 50 gallons per hour. Footprints range from 157/8 inches by 24 ¼ inches to 26 inches by 36½ inches.
The majority of the foodservice segment utilizes gravity-fed machines, which store and refrigerate the mix in the hopper on the top of the freezer. A mix feed connects the hopper and the cylinder. As gravity pulls the mix into the freezing cylinder through the bottom of the mix feed tube, the unit draws in air through the top of the tube. Once in the cylinder, the air blends into the mix by the beater shaft. Once the product freezes, staff can dispense it. The auger on the beater shaft pushes the product out of the cylinder. Because this machine type limits the amount of air in the product, after four hours, the product can get dense and the viscosity more difficult to control.
Pressurized machines, which freeze the product the same way once the mix and air enter the cylinder, also are available. These machines use a transfer system that pumps the mix from a container located in a refrigerated compartment up to the cylinders. While the mix moves up to the cylinder, metered air gets incorporated into the liquid mix. In some instances, the beater shaft may rotate at a slower speed than the gravity machines. Pressure inside the cylinder forces the frozen mix out of the cylinder.
Overrun, or the amount of air introduced into the product, differs with these two machines. While gravity systems typically run at 42 percent overrun, pressurized units run at 60 percent. The greater the overrun, the higher the profit. Pressurized units can more accurately control the ratio of air to product.
Soft-serve machines generate a great deal of heat due to the use of a strong compressor. As a result, these units often come with either air- or water-cooled condensing systems similar to those in refrigeration systems.
Some units feature Wi-Fi, internet logging capabilities to track ice cream production and other computerized features that give operators more control over the end product. A microprocessor controls some of these units’ latest functions. These control interfaces have icons on touch screens for simple operation. A newer option is a heat-treat feature, which allows the machine to operate for two weeks without being disassembled for cleaning.
Safety features are standard within the control. Most machines will automatically warn users if mix is running low, and some keep track of the number of servings. Operators can set the timer to automatically start the machine so the product is ready to serve at a predetermined time. Some units can log cleaning times and report cleaning schedules via email. Self-diagnostic tools help the service technicians diagnose malfunctions. Some machines include an automatic shutoff feature if the unit is not cleaned properly.