Food Engineering

Fabulous Food Plant: FAGE Yogurt

December 1, 2009
This brand-new, nearly lights-out plant employs state-of-the-art process control technology to produce and package a high-quality, consistent product.

Filled and capped containers of yogurt are on their way to X-ray inspection and final case closure.


FAGE Greek-style yogurt is now produced in the US with the opening of a new manufacturing facility in Johnstown, NY.

Yogurt has always been a tasty treat-whether for a healthy pick-me-up snack or a garnish for other foods. Most American consumers are accustomed to a somewhat thin consistency-even in plain yogurt-that needs to be stirred because it settles, leaving water on the top. But that’s not the case with FAGE Total Classic Yogurt. In this traditional and authentic Greek yogurt, you can stand a spoon up in it. It’s that thick and rich. The 2% product tastes a little like sour cream instead of yogurt. Mix it with fruit and it tastes like cheesecake.

As FAGE Production Manager Bernard McConaghy says, it’s a product that is very thick and creamy; nothing artificial is added. “It’s milk, it’s cream and it’s fruit,” he says. “And we ferment the yogurt with a combination of different proprietary cultures-it’s a live-culture fermentation.”

Product consistency, says McConaghy, is a result of the combination of culture, pasteurization process and the separating process. “We separate a large majority of the whey we obtain after the fermentation process. It takes approximately four pounds of milk to produce one pound of yogurt.” Creating authentic Greek-strained yogurt requires a separation process to remove excess whey and liquid. The all-natural yogurt is available in fat-free, 2, 5 and 10% fat contents, in four different cup sizes. Flavored yogurt cups have a side pouch for honey or fruits such as cherry, peach or strawberry.

Inoculation/fermentation tanks are outfitted with process instrumentation, have multiple inlets and include a CIP system with Alfa Laval mix-proof valves. Source: Webber/Smith Associates.

FAGE (pronounced Fa-yeh), which enjoys success in Greece and the rest of Europe, decided to introduce its yogurt in the US and began importing it in 1998. It wasn’t long before demand outstripped its ability to import. In 2005, FAGE USA Dairy was established with the purpose of building a state-of-the-art production facility in the US.

The company signed Webber/Smith Associates of Lancaster, PA, to provide engineering services through AE Design, Inc. and design and build an automated facility. The facility encompasses 115,000 sq. ft. and is situated on a 27-acre site at the foot of the Adirondack Mountains in Johnstown, NY. Since the plant was finished last year, demand for FAGE yogurt has increased and installation of new tanks and equipment is already in progress, as space was set aside inside the building.

Johnstown was chosen for its nearness to New York state dairy farms and favorable pricing of the raw milk supply. In a pinch, milk can be brought in from New England if there is a shortage in New York. According to McConaghy, the local water authority was very receptive to connecting the plant because the treatment facility was being underutilized. In addition, locating the plant near markets with high consumer appeal in the densely populated Northeastern US was a no-brainer.

CIP Controls for Tetra Pak systems are completely automated and connect to the plant’s distributed control system.

Lights out ... almost

What’s truly unique about this plant is the absence of manual operation except for the uncartoning of cups and trays fed into the filling and packaging machines.  McConaghy says, however, that maintenance and some material handling is still manual. Most everything else could be compared to a “lights-out” automobile assembly plant-except that you don’t see the product as it is being made. From the time hormone-free milk arrives in tank trucks to the time finished yogurt-ready for shipping-is put in refrigerated storage, the only point where product is visible to the human eye is during filling into cups by GASTI or HAMBA equipment.

After filling, Aries packaging lines (consisting of tray lid applicators, integrated Smiths Detection X-ray foreign object detectors and tray counters/labelers) finish the labeling and packaging chores, handing off product to an ABB robotics handling and palletizing system. Equipment includes carton erectors, conveyors and carton sealers.

Once palletized, two floor-guided shuttles and one automated cooling tunnel provide conveyance into a high-density Westfalia automated storage and retrieval system (AS/RS) in the refrigerated warehouse.

“We basically are a paperless plant,” says McConaghy. “Certainly we have documentation that we use and rely on that is paper-based, but all the critical plant information is electronic based. The interconnection of all these systems is critical to the plant operating well. It enables us to capture all pertinent data and to rely on that data to optimize plant operations. Our Tetra Pak clean-in-place systems are like any other production system. They are built into the schedule and are pretty much hands-off.”

An operator terminal for a GASTI filling machine employs a Rockwell user interface and connects with a distributed control system in the control room.

Process controls for consistency

What’s interesting about the yogurt process in this facility is it’s akin to brewing beer or making certain drugs-they all use fermentation. And McConaghy has some past experience in the pharma industry, so he’s no stranger to the analytics of the process. In fact, he says, because the yogurt process is very simple compared to the complexity of producing some drugs, it’s very easy to intervene in the yogurt’s fermentation and catch a problem before it changes a batch’s characteristics, undermining the taste and quality of the product.

“We do critical monitoring of the product from reception (typically seven to eight tank trucks of milk per day) through fermentation, and because of the variables we analyze, we can almost always adjust based on the quality characteristics that we see at the fermentation point and after.” He adds, “We don’t [just] necessarily validate process data for regulatory compliance issues, we monitor analytical process data to ensure there are no surprises-a fermentation batch does not behave as expected.”

After incoming milk has been tested in the on-site lab for bacteria, pH, solids, color and odors, it’s automatically pumped to one of four 26,000-gal milk silos. Coriolis flowmeters verify volumetric and weight information obtained from truck weigh scales. Whole milk is segregated from skim milk. Everything in the plant is pasteurized before being processed including water, milk and cream, and each is tested and inspected to be sure of the pasteurization’s efficacy.

The plant relies primarily on Tetra Pak and Rockwell distributed control systems, which not only control the process, but also control the plant’s automated CIP systems. According to McConaghy, the plant is highly instrumented, and the controls maintain product quality and ensure consistency. Micro Motion Coriolis flowmeters are used throughout, and a lot of the instrumentation comes from nearby Anderson Instruments, as well as Ashcroft and Mettler-Toledo. Alfa Laval mix-proof valves are used to handle CIP processes. In the CIP room, one system handles the pasteurized side of the plant and another handles the unpasteurized side.

The control room monitors every process detail, and operators watch pumps, speeds, valves, pressures, flow, level, etc.-all in real time. Depending on the product, a batch process can take anywhere from several hours to a few shifts. Analytical instrumentation also provides the operators and control system with vital information on process variables, allowing fine tuning during the process. Samples are collected and analyzed by the lab staff just off the control room. While all the analytical tests prove the numbers are right, there’s nothing like a taste test to verify product quality, and McConaghy assures that this is done on a regular basis.

In addition to process controls, the control room has access to a building management system provided by Siemens. It provides monitoring of the central plant utilities and control of HVAC equipment. This system can monitor boilers and chillers that already come equipped from the manufacturer with a control system just by tying into it. Operators also have access to a perimeter monitoring system where not only are staff movements checked, but where truck deliveries of milk are noted along with the silos that receive their milk. The system includes 40 cameras mounted in strategic areas of the plant and controlled gates.

This walkway in the interstitial space can be used for maintenance and access to process equipment. Source: Webber/Smith Associates.

Design challenges

Because FAGE produces an all-natural product, it settled on a design that resembles a biotech plant. The 40-ft. inoculation silos were customized with multiple inputs for culture and enough process instrumentation for a pharma reactor. The automated process controls, instrumentation, CIP and aseptic filling machines add to the complexity of this modern plant but are needed to produce a relatively simple product very well.

This complexity produced some real challenges for getting the project started and keeping it going-through a cold New York state winter. According to Gary Smith, Webber/Smith principal, engineering and design were executed during January through June 2006. FAGE arranged for process design directly with Tetra Pak’s headquarters in Sweden.

Challenges to the project included:

• Process design-The process design was not complete prior to the design of the facility, which posed two problems. One was the coordination of utilities to support the process equipment and the other was that process piping would be suspended from the building structure in some places.

• Weather-With construction beginning in September 2006, weather was a serious concern. Foundations had to be in and steel going up before the worst of the cold weather set in.

• Communication-Headquartered in Athens, Greece, FAGE undertook the construction of the Johnstown plant as its first US project, having no prior experience working with a US company for this type of project.

• Logistical concerns-Finding sufficient space for the construction staging area was particularly difficult due to limited workspace to comply with storm water pollution prevention plan regulations. In addition, coordination of air handlers and mechanical piping installation in conjunction with the slab on grade placement and metal wall panel installation posed the greatest logistical challenge.

• Schedule-Scheduling challenges involved getting structural steel on site within three months of award of contract, completing installation of the welded stainless steel (SS) underground plumbing, enclosing the building for winter, building the substation and completing the mechanical/electrical/plumbing (MEP) rough-in to allow the walk-on ceilings to be installed.

On-time completion

All challenges were met by contractors and sub-contractors to deliver an on-time, world-class yogurt manufacturing plant. While use of an interstitial space in a dairy plant is considered normal, some in this facility should be noted. The SS tube system allows the process piping to be attached to the ceiling grid, rather than having to penetrate the ceiling and attach it to roof members. Because New York winters are so cold, air handling units can be located in this space rather than the roof, making maintenance much easier.

The mechanical systems were designed with energy efficiency in mind. All air-handling units are designed with economizers, and variable-speed drives (VSDs) are used on most fans and pumps to reduce energy usage. Boilers have VSDs and stack economizers to pre-heat boiler feed water.

While the facility was built in 16 months, the popularity of FAGE Total yogurt has been placing more demands on the plant. While this is a nice problem to have, McConaghy sees a lot of room for internal expansion without having to push out the four walls. But the facility has room on the site to accommodate an expansion, should that need arise.