Futuristic flash-freeze processing creates Dippin’ Dots ice cream and more in Paducah, Ky.

Processing floor fog, stainless steel frost and the occasional freezer snow flurry underscore the frigid ice cream processing temperatures found at the Dippin’ Dots facility in Paducah, Ky.

The company uses -320°F liquid nitrogen inside custom cryogenic processors to flash-freeze ice cream into tiny dots. The concept was pioneered in the late 1980s by Curt Jones, founder and president. His love of homemade ice cream and his microbiology career dovetailed to create ice cream with minimal ice crystal formation for maximum creamy mouthfeel.

Early processing in a 400-square-foot garage on the founder’s family farm soon expanded to a rented, 2,000-square-foot space in a former liquor store in Paducah. In 1995, the company opened its custom-designed 20,000-square-foot Dippin’ Dots facility and 6,000-square-foot kiosk/equipment assembly operation on a 17-acre light industrial tract on Paducah’s outskirts. A series of processing, warehouse and freezer expansions have since grown processing operations to 120,000 square feet and kiosk operations to 18,000 square feet.

Capacity and efficiency of the plant’s cryogenic processors, called CP units in-house, have likewise evolved. The company’s original CP unit made 4 gallons of ice cream dots per hour. The fifth-generation CP units now create 60,000 gallons per week – the equivalent of 3 billion tiny frozen dots.

Bulk gallon bags and single-serve packages are held in -40 to -50°F freezer space, then are shipped around the world in -100°F totes and cooler boxes. Customers store the product in Dippin’ Dots-provided freezers that hold product at -40°F prior to serving to consumers in venues, including malls, theme parks and movie theaters.

Maintaining even, deep-freeze handling is critical to prevent clumping of the free-flowing frozen pellets. “The product itself is a built-in quality control feature,” says Rick Noble, Dippin’ Dots director of operations.

The facility produces more than 40 varieties of Dippin’ Dots in ice cream, sherbet and flavored ice varieties as well as coffee product versions of dots. In May, frozen yogurt dots will roll out from the plant for franchisee and foodservice account launches. In March, a filling line already in place to create Dots ’n Cream retail ice cream half-gallon cartons began creating Dippin’ Dots Ice Cream Cakes. Both products are designed for merchandising in standard freezer cases.

“We’re continually trying to improve our process, improve our products and improve the range of markets that our products can go into. That’s all part of our long-term goals,” says Stan Jones, the company’s director of research and development. The two Jones, unrelated, are college pals and long-time collaborators. Stan Jones created the CP units and headed the Paducah facility’s original design-build as well as subsequent expansions. 

Proximity to southeast Illinois draws facility employees from both sides of the state line. The plant currently has 135 full-time employees, and adds flexibility during peak production periods with temporary workers. One full shift is dedicated to production five days a week, with a second shift for maintenance and sanitation.

Mix mode

Creation of the unique beaded ice cream creation starts with a traditional frozen dessert approach. The Dippin’ Dots facility purchases plain and chocolate 10% butterfat ice cream mix from cooperative Prairie Farms.

The plant’s single receiving bay accepts an average of four loads of mix totaling 20,000 gallons per week, and handles double that volume during peak production periods. The mix for Dippin’ Dots is treated as raw product, and is subject to in-house lab tests, including standard plate count, coliform, temperature and viscosity, explains Glen Thompson, quality assurance manager. 

Federal and state-level inspections and certifications along with third-party and in-house audits ensure Dippin’ Dots processing capabilities and ongoing HACCP certification. A rabbi visits the facility’s production six times a year for kosher certification. In addition, the company’s suppliers document HACCP programs and ingredient allergen potential.

Samples are additionally taken prior to pasteurization, at the flavoring tanks and from finished product as part of the internal audits that follow quality assurance checklists at each phase of the process, Thompson says.

Once accepted, mix is held in receiving in three 20,000-gallon silos and the plant’s original 6,000-gallon silo. Mix is pumped from receiving silos to the HTST pasteurizer on the processing floor. It is pasteurized at 175°F for 28 seconds at 6,000 gallons per hour, and then pumped into one of three 20,000-gallon silos dedicated to pasteurized storage.

The base ice cream mix for Dippin’ Dots is then pumped to a dozen 200- and 100-gallon flavor vats. Bulk flavors are measured from drums and poured manually into the vats in a 23-28 minute process. Careful timing and creative batching allows the plant to create up to seven different varieties per production shift. For instance, vats for chocolate in the morning shift to chocolate mint in the afternoon. 

Multi-flavor Dippin’ Dots products require simultaneous use of multiple flavor vats – Banana Split uses four vats to combine banana, chocolate, strawberry and vanilla dots in one package. Vat operators carefully synch mix levels and pump speeds with production pace to keep required flavor proportions. Flavor vat mix levels are monitored with a “good old-fashioned measuring stick for less glitches” than automated systems, says Robert Reams, vat operator.

Drops to dots

The individual mix flavors are pumped through clear tubing to the CP units where mix is transformed to Dippin’ Dots. The CP unit pan sprays the flavored mix out in tiny droplets. Gravity pulls droplets into the tank of -320°F liquid nitrogen. The near-instant transformation from fluid mix to bb pellet-sized ice cream beads minimizes ice crystal formation, the  “secret” behind the creamy mouthfeel of Dippin’ Dots products.

The flash-frozen beads sink in the CP vat’s liquid nitrogen. Augers move the free-flowing, -180°F ice cream beads to the filler.  Frigid temperatures inside the CP unit create frost on the exterior of the filler line and can freeze the stainless steel feed to the filler nozzle. Preventative action includes a heat gun mounted to blow into the filler; it is activated when the equipment begins to squeak from the cold.

Inclusions such as crushed cookies for Dippin’ Dots No. 1 flavor, Cookies ‘n Cream with Oreo, are added via a manually fed hopper on the bulk filler. The company uses 4 tons of Oreo inclusions each week.

Line workers use pedal releases to drop dots and inclusions from the filler into plastic gallon bags. Bulk bags are weighed, then manually heat sealed and boxed six-gallon bags to a carton.  Experimentation with filling line efficiencies to reduce manual handling has yielded unsatisfactory results, says Noble. “It’s a process that is difficult to automate due to the extremely low temperatures.”

The cartons are placed on a conveyor and travel at an incline off the processor floor to palletizing; products are then moved to the freezer via forklift.

The bulk CP units are also used to create flash-frozen espresso dots for the company’s Dippin’ Dots Coffee line, launched in 2009. An industrial-sized espresso machine extracts espresso from Brazilian and Guatemalan Arabica coffee beans. The espresso is then immediately converted into dots.

The Dippin’ Dots Forty Below Joe Edible Coffee features the frozen espresso dots as well as frappé in caramel, mocha and vanilla flavors.  The versatile espresso dots can also be heated to create espresso or coffee-based drinks with fresh-pressed taste.

Dots on the go

In space adjacent to the bulk CP units, the plant creates pre-packaged dot products for merchandising via vending machine, single-serve freezers and school systems.

The pre-pack Dippin’ Dots line averages 6,000 3-ounce packs per day. Capacity is 8,000 packs per day, but is deliberately slowed to prevent equipment failure. “The use of nitrogen and ultra-cold temperatures tends to wear parts,” Thompson says.

A CP unit forms the dots, which are then routed to the filler. The line can also fill 50 gram, 2.5- and 7-ounce packs as required.

A new inclusion feeder for the pre-pack line to be online by the end of May will phase out the current multi-step process for inclusion-laden varieties. Without the feeder, bulk gallon bags of pre-mixed Cookies ‘n Cream with Oreo dots are transferred from the adjacent bulk filler to the pre-pack line via wheeled dry ice tote, then poured into a manual feed hopper on the pre-pack unit’s filler.

A puff of air opens the pre-formed pouches, and dots automatically drop in. Pouches are sealed and hand packed 50 to a carton. The boxes are then transferred to the conveyor system, which whisks product to palletizing and then to freezer storage.

Cake creations

The Paducah facility added ice cream cakes to its line-up in March. The newest and most labor-intensive addition to the plant’s processing capabilities, the cake line utilizes expertise and equipment already in place for the company’s retail half-gallon Dots ‘n Cream ice cream line. However, the new product has required additional staffing, as 34 line workers are involved in the assembly line-style cake creation from start to finish.

An East Coast co-packer established Dippin’ Dots cake distribution through select retail chains. Initially, Paducah cake production will be dedicated to a frozen food home delivery service partnership. Unlike the special freezer accommodations required for dots, both Dots ‘n Cream  and the cake lines can be held in standard ice cream cases.

Pre-made dots are added to ice cream mix via an inclusion hopper to create one of two cake varieties, Cookies ‘n Cream or Rainbow. The dot-infused ice cream pours out of the filler at soft-serve consistency into 6-inch round plastic cake molds at a rate of five per minute, about half of potential capacity.

A line worker uses food-grade cardboard to smooth the dot-infused ice cream at the bottom of the plastic cake mold, then uses the cardboard to create a bottom seal. “The actual temperature of the dots when introduced to the ice cream mix immediately begins to freeze the cakes from the inside,” Noble says.

Cake molds are then transferred to a conveyor for a trip through the -200°F freezer tunnel. The rapid internal freezing combined with the tunnel creates an ice cream cake with creamier-then-regular ice cream texture, Noble says.

The day’s run of Rainbow Confetti Cake hard freezes in the tunnel at a rate of 17 minutes, 50 seconds per cake. The ready-to-decorate “blanks” are held in dry ice-filled shipping containers to await decorative touches.

Line workers remove cakes from plastic molds for the decorating process; the food-grade cardboard acts as a holder. Employee-operated mechanical icing equipment smoothes butter cream frosting on cake exteriors. Cakes are inspected for frosting gaps and touched up as necessary.

The cake is then passed to a “dollop” machine, where an employee guides application of decorative frosting around the cake top’s edge. The next worker sprinkles a colorful mixture of Rainbow flavor Dippin’ Dots onto the cake top. Next, “stringers” of blue and red frosting are hand-applied to the cake top by two more line workers.

Cakes are then placed in pre-formed bakery-style cake boxes, run through the metal detector and date coded. Cake boxes are shrink-wrapped, packed eight to a shipping carton, and sent via conveyor for palletizing, freezer storage and distribution.

Freeze for all

The ultra-cold 380,000-gallon-capacity storage freezer is kept at between -40 and -50°F. A two-door entry system leads from palletizing and distribution areas to a staging area. Once inside the insulating pocket, a second set of doors permits full entry into the freezer, where palletized products are stored on racks and forklifts leave tracks in the snow generated by the occasional updraft.

The freezer uses a pallet racking system to optimize storage space, much more accessible than the facility’s original pit freezer. The non-mechanical freezer pit harnessed the liquid nitrogen gases from the CP units; product pallets were lowered and lifted with a crane. When the pit’s capacity began to be strained and product retrieval impractical, the pit replaced with a 90,000-gallon capacity freezer. Freezer space has since expanded, first to 180,000-gallon capacity, then to the current 380,000-gallon capacity.

Dippin’ Dots products are shipped via commercial carrier in custom-designed, pallet-ready shipping containers. Each holds 360 dot gallons at -100°F with a four-day supply of dry ice in a bunker compartment. Dry ice is also used in one-way lined freezer cartons. The plant uses an average of 45,000 gallons of liquid nitrogen per week and an additional 20,000 pounds of dry ice.

Use of liquid nitrogen and dry ice requires close attention. In addition to the cold, oxygen displacement is a real hazard. “Keeping airflow moving is a top priority. A return air system and exhaust fans keep air flowing.  We also have oxygen monitors to warn us if oxygen levels drop below the required level,” Noble says.

Employee safety is also ensured with a well-organized safety program. Department-specific safety meetings are held weekly for all employees, and include GMP training for all employees; new production staffers also receive GMP safety training.

The facility ships domestically and worldwide to countries, including Mexico, Canada, Australia, the Philippines and Kuwait. Upon delivery, Dippin’ Dots products are stored in company-supplied freezers to maintain -40

At a Glance: Dippin' Dots, Paducah, Ky.

Year plant built: 1995
Description of additions/renovations: Original 17,000-gallon capacity “pit” freezer  chilled with liquid nitrogen replaced with traditional above-ground freezer (1997); new silos, pumps, HTST pasteurizers, bulk cryogenic processors, freezer expansion (2004); freezer, warehouse, shipping expansion (2006); pre-pack filler line added (2007), espresso press (2009).
Size: 126,000 square feet on 17-acre tract, including 18,000-square-foot kiosk/equipment assembly shop.
Number of employees: 170 total, 135 production
Products: Dippin’ Dots ice cream, sherbet, yogurt, cake and coffee.
Total processing: 60,000 gallons of ice cream dots per week.
Milk receiving: One bay, average four loads Prairie Farms ice cream mix per week (20,000 gallons a week, doubles during peak production); four silos-three 20,000 gallon, one 6,000 gallon.
Pasteurization: One HTST pasteurizer, 6,000-gallon per hour; three pasteurized mix silos, 20,000 gallons each.
Production lines/types: Five custom cryogenic processors (CP); four bulk lines fill 26,000 1-gallon bags per day. Pre-pack line fills 6,000 3-ounce pouch packages per day, 8,000-pack capacity; alternate size capability. 
Finished product freezer: 380,000-gallon capacity, -40 to -50°F; 17,000 square feet.
Kiosk production: 18,000-square-foot shop for construction of kiosks, carts, stands and other point-of-purchase sales equipment.
Dry storage capacity: 20,000-square-foot dry storage warehouse for ingredients, packaging, other dry good.
Unique equipment: Fifth-generation custom cryogenic processor units use liquid nitrogen to flash freeze ice cream mix droplets.