Ice is one of the most important “foods” sold in restaurants. If you have ever run out of ice, you know just how important it is. Most ice shortage headaches are avoidable by proper equipment selection, sizing and maintenance. Problems with continual service calls are also often avoidable with proper maintenance and the help of new user-friendly accessories available on some machines. But arguably the biggest two issues to consider are the unit capacity and ice style.
There are two basic types of ice made by two different types of machine processes. The classic ice type for beverages is cube ice. Cube ice is clear and appealing for beverages. Commercial-quality cube ice differs from the type made in ice trays. Commercial ice makers produce ice in a somewhat different way than you do at home for better quality and much higher production. Flaked ice is the other main ice type. Flakes are ideal for rapid beverage cooling but tend to water down the drink too much for most customers. Flaked ice can be used in beverages but a newer “better” drink ice has been invented, sometimes called “nugget” ice. This ice is most similar to compressed flaked ice formed into small cylinders. This ice is not as crystal clear as cubes but is hard and slower to melt than flaked ice. The product is formed in an easy-to-chew sized nugget, which is desired by many customers for beverages, especially in quick-service operations. Nuggets have already been adopted by a number of quick-service chains and are likely to become more popular. The process of producing nugget ice requires less water and significantly less electricity than producing cubes, so it is less costly to make. Nugget machines are also a bit more compact and require less maintenance.
A key reason to choose one type of ice over another is its melting characteristics. Simply put, a cube tends to melt more slowly than flaked ice because it has less surface area and there is no water trapped inside like with flaked ice. The slower melting of an ice cube waters down a beverage less than flaked ice. Flaked ice, however, does have an important place in the back-of-house operation of a kitchen. Because it melts quickly, flaked ice transfers heat and chills product quickly. Flaked ice is handy for holding items like fresh seafood and chickens or for rapid chilling tasks. Nugget ice generally melts more slowly than flaked ice but more quickly than cubes. These qualities make the nuggets effective in keeping soft drinks cold while allowing the ice to last for a reasonable amount of time.
Once you choose the ice type, deciding which size ice maker you need can be difficult because there are so many variables. Ice needs are rarely the same in any two operations. Requirements generally fluctuate depending on type of operation, day of the week and season. While it is difficult to predict, there are a few rules of thumb regarding ice usage:
Restaurants: 2 pounds of flaked/cubed ice per person
Salad bars: 30 pounds of flaked ice per square foot
Quick-service restaurants: 2 pounds of cubed ice per person
Bars: 3 pounds of cubed ice per person
These usage amounts include ice melting in the bin and waste. They also factor in back-of-the-house ice uses, such as the flaked ice applications mentioned earlier.
Once you figure out how many pounds of ice you need each day, you then need to match your needs with a machine. Some of the production claims can be misleading if you don't know what to look for. Be careful to note that many manufacturers' ice-making claims are based on 50°F water and 70°F air at the ice maker. These temperatures are often unrealistic; in many areas incoming water temperature exceeds 50°F, especially in the summer when ice needs are greatest, and the air temperature in the restaurant may be higher than 70°F. Exceeding these ideal temperatures negatively impacts the machine's production capacity — usually just when you need ice most. The best way to avoid running out of ice on your hottest peak use days is to buy enough ice capacity from the start. You want to buy ice and storage capacity for your peak demand, not just your average demand.
To get a realistic idea of an ice maker's capacity, take into account the actual expected air and water temperature to ensure enough ice can be produced. As a rule of thumb, a 10°F air temperature increase may reduce an air-cooled machine's daily production by 10 percent. In addition the higher room temperature will melt ice in the bin faster, requiring more ice-making capacity to replenish and fill the bin. The use of water-cooled ice makers, especially for larger machines, can reduce the amount of heat the ice maker itself adds to the kitchen. The amount of heat generated by air-cooled machines is significant, especially if located in a small confined area or a space you may be trying to air-condition for the comfort of kitchen staff.
Air- or Water-Cooled?
The choice of an air-cooled or water-cooled machine is an important one. Ice makers use either air or water to cool their refrigeration compressor and condenser system. Each has advantages. The air-cooled condenser is cost effective and involves no added water costs. In most areas water-cooled machines must be on a closed-loop system, meaning no water can be dumped down a drain. A closed loop and cooling tower may or may not be feasible in your store, however. In addition to dispersing less heat than an air-cooled machine, the water-cooled system does have some significant advantages in machine efficiency. A water-cooled maker usually consumes less electricity than a similarly sized air-cooled machine. Water-cooled units are also quieter for areas where noise is a factor. If water cooling is practical in your operation, use it.
A variation of the air-cooled system is a remote condenser unit that offers some advantages of its own. The remote unit takes the biggest heat producing component, the condenser, out of the ice maker and your store altogether. The remote approach does not require water and removes most the heat from the service area. The condenser can be located up to about 50 feet away, perhaps on the roof. Remote ice makers are also quieter than typical machines because some of the machinery has been relocated. Tightly packed restaurants are a good application for remote equipment because of the reduced noise and heat they produce.
Regardless of whether you choose air- or water-cooled equipment, you will want to look for a machine with an Energy Star label for the best efficiency.
Other Factors in Ice Production
Two additional factors will ensure your unit will provide quality ice. First, never underestimate the importance of a water filter for your ice maker. Water filters condition incoming water, reduce the machine's necessary cleaning frequency, allow top equipment performance and improve the taste quality of your ice. Lime and mineral buildup will be greatly reduced inside your maker if you use a filter. You should install a good quality water filter and follow the directions to change it when needed.
The second consideration is maintenance. Maintaining your ice maker properly is critical to productivity, food safety and quality ice. Since many health departments consider ice a food safety concern, cleaning and sanitizing ice machines are critical. One feature you may want to consider is automatic, internal self-cleaning systems for the machine that include built-in sanitizers and cleansers. Even if you have automatic cleaning options, you should still set up and perform a regular internal cleaning and maintenance schedule or contract with a service agency to do the work for you. The most important thing to remember is to choose the machine that best meets your needs — and take care of it.
Dan Bendall is a principal of FoodStrategy, a Maryland-based consulting firm specializing in planning foodservice facilities. He is also a member of Foodservice Consultants Society International. Bendall can be reached at 301-233-5226 (email@example.com).