A vacuum conveyor improves both productivity and efficiency at a food processing plant resulting in slimmer waistlines for consumers and fewer strained backs for workers.

YoFarm plant engineer, Peter Riebe, stands in front of the vacuum conveying system, displaying the YoCrunch topping. The conveying system is used to fill the plastic domes on top of the yogurt cups.

The packaging process is now entirely hands-free, as measured amounts of dry food are pneumatically transferred to the filler machine using vacuum conveyors, eliminating any risk of employee back strain.


Yogurt has been a longtime favorite among people trying to eat healthier or watch their waistlines. Unfortunately, for some, the creamy texture and taste are equated with a certain blandness. In recent years, manufacturers have come up with various ways to spice up the yogurt offerings found on grocery store shelves. YoFarm, based in Naugatuck, Conn., is one such company. Founded in 1984, YoFarm has always been an innovator in the food industry, both in terms of its product and its processing and packaging. In 1985, YoFarm pioneered the ready-to-eat dessert/snack category with its single-serving jelly cup.

The company created a whole new yogurt category in 1991 with the introduction of the first yogurt/granola topping combo pack. This new treat, called YoCrunch, combined the company's mild yogurt in a low-fat form with an accompanying packet of granola as a single-serve offering to be mixed together by the consumer. Extremely well-received by both the public and the industry, YoCrunch earned both product and packaging awards. The company has since added some popular variations to the YoCrunch line, with a chocolate crunch topping in 1994, a Cookies n' Cream product with Oreo cookies in 1998, and a Strawberry YoCrunch with Nestle Crunch pieces in 2003.

In 2002, YoFarm decided that its packaging process needed to be upgraded, both to keep up with growing production demands and to improve efficiency at the plant. To improve operations and productivity, the company decided it wanted to specifically automate the process of transferring the dry YoCrunch ingredients from 2000-lb. totes into the domes, the plastic containers that sit atop the yogurt cup.

For years, this had been a manual operation — it was both time consuming and labor intensive. Operators would literally scoop the granola or dry ingredient out of the enormous tote using a stainless steel bucket and carry the food over to a filler machine. The operator would be responsible for monitoring the right quantities using the cup as a guide.

In its quest to find a less laborious, safer and more efficient transfer system, YoFarm turned to Piab, Hingham, Mass., known for its industrial vacuum conveying technology, to purchase a state-of-the-art, USDA and FDA-approved vacuum conveyor system.

According to YoFarm plant engineer, Peter Riebe, "Our production capacity has increased by more than 40% over the last few years. We needed a transfer system that could keep up with increased productivity and make us more competitive and profitable, while reducing the physical strain on our employees. The C-33 conveyors had everything we were looking for in terms of functionality, hygienic safety, and quality."

Piab's C series conveyors are designed to safely and quietly transport up to 15 tons/hr of powders, granules, and food in virtually any manufacturing environment. Made of stainless steel, the conveyors meet all the standards for hygienic safety, feature corrosion-resistance, and are easy to clean.

Riebe comments, "Another benefit we received was the ability to test the flow of the products under real conditions at the testing lab."

Piab offers the use of its test facility in Hingham to all of its potential customers, running a variety of materials to determine their conveying characteristics as well as identifying any possible issues.

With two C-33 vacuum conveyors in place, the YoCrunch dry ingredients are now transferred in a safer, completely automated system. The packaging process is now entirely hands-free, as measured amounts of dry food are pneumatically transferred to the filler machine, dropped in the domes, thermally sealed, and then mated with a container of yogurt. The machines run 24/7, with no risk of human error — and the quantities are always exactly correct.

"The conveyors have taken the manual labor out of the process," Riebe said. "There is now no risk of employee back strain, as the operators just have to run the machines and monitor the process. They are much happier in their work."

Modular in design, the C-33 vacuum conveyor facilitates fast installation and requires one simple connection to compressed air. It has minimal components, small dimensions and is lightweight.

According to Riebe, "The C-33 is a very reliable, well-designed, and extremely clean system. Our employees appreciate the fact that it is simple to operate and requires almost no maintenance. And our inspectors like the fact that it eliminates almost all risk of contamination. Removing the potential for injury from the packaging process makes for a very stress-free, happy, and productive work environment."

Contact Piab in the US at (800) 321-7422 or click here.

How a vacuum conveyor works

  1. Vacuum is generated by compressed air-driven vacuum pump A. The pump can be controlled automatically. Because it has few moving parts, the pump is virtually maintenance-free.
  2. Bottom valve B is closed, and vacuum is raised in  container C and  conveying pipeline D.
  3. From  feed station E, the material is drawn into the conveying pipeline and then on to the container.
  4. Filter F prevents dust and fine particles from being drawn into the pump and escaping into the surroundings.
  5. During the suction period,  air shock tanks G are filled with compressed air.
  6. When the material container is full, the vacuum pump is stopped. The bottom valve opens, and the material in the container is discharged. At the same time, the compressed air in the filter tank is released and cleans the filter.
  7. When the pump is restarted, the process is repeated, and a new cycle begins. The suction and discharge times are normally controlled by a pneumatic or electrical control system, H.