FER FOCUS: Panning For Gold In Nugget Ice

It’s time to think about your icemakers. Some need replacing or soon will. Technology keeps changing as do consumer tastes. Will you stand pat on your existing specs, or will you make a change?

Cubers have been around forever, and today’s models are modern marvels of reliability, self-diagnostics and utility efficiency. Cubers work, and most of the market still uses them.

But you have other choices, too. Everywhere you go, someone is talking about chewable ice. First hitting the market back in the late 1970s to the early ’80s—mainly in hospitals looking for a handy way to hydrate patients—compressed-flake ice has grown increasingly popular. Today, six of the big icemaker manufacturers offer their own takes on compressed flake, or what many refer to as “nugget,” ice. It goes by several names, and some manufacturers put their own spins on it—chewblet, cubelet, chiplet—but it’s all soft and chewable.

So why the buzz about nugget ice? It’s not for everyone or every application. But it might be for you. 

Chew On This

“We love the fuss about chewable ice,” one manufacturer says. “We’ve commissioned independent companies to do consumer customer-intercept surveys,” mainly at convenience stores and QSRs, he says. The results? “Seventy percent of consumers prefer chewable ice. And there are two other important numbers,” he adds. “Forty percent of consumers say they would drive out of their way for chewable ice, and 55% say they would make more fountain purchases because of it.”

Nugget ice appears to be a thumbs-up in the “increases revenue” column, at least in certain segments—and, it turns out, in certain geographic areas. All of the suppliers we talked with report that the trend is strongest in c-stores and QSRs and in the South and Southeast in general, and it’s spreading from there. It figures, really. People in hot climates, especially people on the go, will most naturally appreciate the crunchy cooling effect of nugget ice. Several suppliers credit quick-service icon Sonic for driving the popularity of nugget ice, and they point out that in some areas, especially in the South and Southeast, consumers call it “Sonic ice.”

Is nugget ice for you? And if so, what do you need to think about? Well, a lot of consumers are chewers. Nuggets are good for soft drinks; some icemaker manufacturers (and nugget-ice fans) say they extend the carbonation effect of sodas. “They’re good for margaritas and smoothies, too,” one manufacturer adds. “They absorb flavors. And nuggets are easier on blender blades.” She notes, too, that higher-end operators who emphasize “perfect” cocktails are tending to go to nuggets for more consistent results in textures and flavors. On the flip side, however, slow-sipping liquors, such as whiskeys and scotches, will call for a hard, long-lasting cube.

Nugget ice also works well for other things. It’s easy to scoop, so it works well for iced displays on buffets, beer troughs and salad bars; containers can nest in nugget ice. It’s good for any operation with short meal periods; there is no point having cubes that last longer than the lunch break.

Which brings us back to melt rate. Does nugget ice melt more quickly than cube ice? Typically, yes, but not necessarily so. “Melt rate is mostly a function of surface area, of which compressed-flake nuggets have a lot,” another supplier points out. “This also means faster beverage cooling.”

Density is another factor in melt rate. Cubes are not literally solid, but they’re generally regarded as being 100% solid. Nuggets are a mixture of ice, near-frozen water and air. Some icemaker suppliers produce nuggets that are almost as dense and hard as cubes, and those nuggets don’t melt much more quickly than cubes. Other nugget makers, on the other hand, produce softer nuggets in the range of 70%-90% ice density. They chill liquids—and melt—more quickly than cubes.

Making The Leap

If nuggets make sense for you, you’ll find nugget machines are similar to cubers in some ways but different in others. First, they come in similar sizes, from countertop units to undercounters and floor models with daily production capacities ranging from under 400 lb. to more than 1,500 lb. Nugget machines come with electrical requirements similar to cubers and similar choices for air- or water-cooled versions, and those with remote or self-contained condensers, etc.

Another question we asked manufacturers was about sizing the machine for production requirements, and, apparently, it was a strange one—like asking your parents why the sky is blue. Given that nuggets are usually less dense than cubes, which means a given volume will weigh less, we thought the number of pounds an operator would need per day might be different. But no, all of the suppliers said. The ice-type differences aren’t enough to change the sizing of your icemaker. If you’re using 8 oz. of cube ice in a 12-16-oz. drink now, you’ll use a similar, if not identical, amount of nugget ice. So if you’re using 1,000 lb. of cubes per day, you’ll be looking at the same production machine for nuggets. Some of the suppliers have calculators on their websites. 

There might be one caveat to the calculation, however: One maker noted that if you’re running self-serve dispensers, you might find customers will fill their cups higher with nugget ice. But again, this might not be enough to make a difference in your machine sizing.

Lower Utility Consumption

As for energy and water, nugget machines use less. Way less. Typically they use about 35% less water—say, 12 gallons of water per 100 lb. of nuggets vs. 18 gallons for cubes—and 10%-15% less electricity. Because the Energy Star icemaker standard was updated in 2013 and now addresses nugget makers, several models are Energy Star qualified.

To understand why a nugget machine uses less water and energy, consider how it works compared with a cuber. A typical cuber system runs water over an evaporator grid where it freezes in layers until cubes are formed. The system then uses a form of heat to release the cubes into a bin. Any residual water, as well as sediment that’s pushed out of the water as it freezes, drops into a sump. The icemaker might flush the sump, either after each cycle or on a periodic basis.

In contrast, a nugget machine runs water into a cylinder-shaped evaporator. Details vary from maker to maker, but they all work similarly. Water freezes on the inside wall of the cylinder and a rotating auger scrapes the ice off in flakes and pushes it toward an orifice or nozzle. At that narrow point, any excess water is squeezed out, and the ice is compressed and extruded into its final nugget shape. The process is continual, not batch-based. There’s no dump, and the need for flushing is reduced. The result: Less water and energy is used.

Different Maintenance And Lifecycle

This doesn’t mean you can run to the bank with all of the savings. There are some tradeoffs for potentially higher drink sales and reduced utility consumption. Nugget machines might tend to be a little more expensive up front, and they need different kinds of maintenance.

“If a typical cuber lasts 10 years, a nugget machine might last eight,” one manufacturer estimates. “If you maintain either machine properly, each type could last twice as long.” The moral of the story: Following maintenance schedules is important.

Another consideration is filtration, says Scott Hester, v.p. at Refrigerated Specialist Inc., Mesquite, Texas. “You need filtration to control sediment and scale. Granular solids will grind away at water seals, bearings, augers and evaporators.” Filtration is even more important in nugget makers than in cubers because nugget machines don’t do the dump and flush.

Without proper scheduled maintenance, the evaporator/auger/gear assemblies are most likely to pay the price, Hester says. But the refrigeration deck on a nugget machine is more bulletproof than on a cuber, he says, and without a hot-gas defrost cycle like cubers use to release the cubes, nugget machines put less stress on compressors. Instead, that stress shows up in the evaporators. 

“The big maintenance issues are not daily but more related to the ‘deeper clean’ issues,” one of the suppliers says. “Any ice machine needs a professional cleaning at least once every six months. … For most brands, but not all, you have to do the auger-motor bearing inspections every six months, too,” he says of the compressed-flake machines. “If you don’t, you can be looking at a catastrophic failure, and then your nugget machine is down.

“Generally, cubers tend to be more cost effective up front, and then operating cost-effectiveness leans toward nugget machines,” he figures. Another supplier notes that the sump systems on cubers require a fair amount of cleaning attention to avoid biofilm (e.g., slime and mold) issues, and the closed-cylinder systems on nugget machines are less vulnerable to those problems. They’re not impervious, but they’re less problematic.

In any case, and especially if you have any doubts that the maintenance schedule might get neglected, Hester recommends leasing instead of purchasing to standardize the cost of the unit per month over time. 

Check out the Gallery for details on specific models from the five big makers.