LOTS AND LOTS OF MOZZ

Dairy Field, Nov 2004 by Dudlicek, James

Leprino's Lemoore West plant stands as a symbol of quality and efficiency.

Perhaps the most amazing thing about the world's largest mozzarella cheese factory is that it was built with expansion in mind.

Leprino Foods Co.'s Lemoore West facility in Lemoore, Calif., already can process 6 million pounds of milk a day, but the company is ready to double that if necessary. The $300 million plant, on a 100-acre site just off Highway 41 about 45 minutes south of Fresno, follows a linear design that allows production to be enlarged in increments of 3 million pounds. At some stages of production, expansion can occur within the existing walls, according to Bob Delong, Leprino's senior vice president of production operations.

The plant turns that milk into more than 600,000 pounds of mozzarella and cheese blends every day - reportedly enough to cover about 800,000 pizzas in several forms, including Leprino's patented QLC® (Quality Locked Cheese) frozen shreds. The facility also manufactures lactose powder and whey protein concentrate.

With constant demand from Leprino's many customers, including the country's best-known pizzeria chains, time and efficiency are of the essence. "We can take a load of milk and have it on a pizza in six hours," plant manager Steve Becker remarks.

Opened late last year, Lemoore West is one of nine plants Leprino operates around the United States and is a companion plant to the company's Lemoore East facility a couple of miles away.

The Lemoore West plant is integrally linked by an access corridor that runs about 1,500 feet from end to end. That's a lot of ground to cover, so let's get started.

Taking it All In

The raw-milk supply for Lemoore West is managed by Dairy Farmers of America (DFA), which collaborates with California Dairies Inc. to ensure delivery obligations are met. The milk comes from farms in Tulare and Kings counties, dairies of some 1,000 head each in the richest milk production area in the United States.

The plant's six drive-through bays can receive up to 1 million pounds of milk per hour from trucks arriving on a continuous basis. The bays are also used to load products like sweet cream for shipment across the country.

Upon arrival, raw milk is tested for temperature, pH and antibiotics. When it tests clean, the milk is offloaded into six silos, each with a capacity of 1.2 million pounds, or 150,000 gallons. Constructed on site, the silos rest on 6-foot-thick concrete footings, required to comply with California's earthquake codes, says Mike Reidy, senior vice president of procurement, logistics and business development. Automatic sampling equipment draws raw milk for component testing.

Two agitators in each silo keep everything moving, with raw milk pumped out for pasteurizing followed by cleaning in place. "It's a challenge to wash them because of their size," Becker says of the silos. "You have to slowly heat them up or it could result in structural fatigue."

Controlled by touch screens, two HTST pasteurization lines handle 182,000 pounds of milk per hour. Milk is than standardized to the desired fat level with an infrared system that analyzes the milk every 30 seconds for its fat-to-protein ratio, Becker explains. Sweet cream pulled off the raw milk is stored and sold.

The starter room features an HTST system linked to eight starter processor tanks and two starter media mix tanks. Starter, developed using a mother culture from the lab, is added to the pasteurized milk inline on its way to the cheese vats, where rennet is added.

Curds ...

A fully automated system controls the 20 cheese vats, 10 each under the guidance of two plant operators. The computer-integrated manufacturing system, or CIM, keeps a detailed record of every batch that passes through the vats, including lab results. Leprino developed the control system, which links operations at all of the company's plants with the corporate office in Denver, from where everything can be monitored and process data easily analyzed.

After 20 to 25 minutes of ripening and setting, the cultured milk forms a gel-like consistency, Becker says. Once the gel-like mass is achieved, the curds are cut by the agitator blades. Curds are then cooked followed by a predraw of some of the whey from the vat. Finally, after a short period of settling, the remaining whey is pumped off.

"This is the 'art' part of it," Becker says, "how long you have to cook it to get the right compositional level."

Curds are then moved onto the dewheying and matting conveyor, or DMC. Distributed across a belt, the curds gradually form into a mat as whey continues to be expelled and acid develops. "This is one of the most critical steps. You do the fine-tuning here," Becker says.

Drained whey is sent off to be clarified and separated for later use. The curd mat is transferred into a cookerstretcher of Leprino's own design, which heats the curd and continues to drain off liquid. "It melts the cheese and stretches it as if you were making it by hand," Becker says.

Salt is added before the evolving cheese is sent to the block molders. Flowing through a pipe in a "molten" state, the cheese is conveyed into a hopper that feeds to an auger that pushes the cheese into the carousel block molder from below. The molder creates blocks of 6, 10 or 20 pounds, which are pushed out of their molds by metal fingers into a brine flume.