UMass-Trained Engineer Serves up Sweet Solution for Ice Cream Manufacturer

January 10, 1997


AMHERST, Mass. - A UMass-trained engineer has served up a technically sweet solution for a western Massachusetts ice cream manufacturer.

The Friendly Ice Cream Corp., makers of a beloved treat in New England and the northeast for some 61 years, has always prided itself on exceeding governmental standards for producing high-quality ice cream. Eighteen months ago, the company sought to make improvements on its Wilbraham production line: its wax-coated boxes were occasionally overfilled. The situation presented a mystery: the same experienced ice cream makers controlled the process in the same way, using the same prime ingredients, every day.

Friendly’s brought on Cher Nicholas, then a UMass graduate student, to make some suggestions. Nicholas had entered the UMass graduate program in mechanical and industrial engineering after seven years in industry. She took on the overfilling question as the basis for her master''s project, working with Friendly’s senior industrial engineer Ron Gathro - himself a UMass grad. Nicholas’s professor, quality engineering professor Lawrence Seiford, says that such projects provide an opportunity for the University to reach out to nearby industries - and for industries to tap into the University’s resources.

"It''s a win-win situation, for the University and for industry," says Seiford. "It''s a form of outreach. Industry gets the task done, and the students get exposed to real life situations in industry."

Ice cream-making at Friendly’s is still very much a craft, so Nicholas began by talking with plant operators at every step along the line at Friendly''s production facility, asking how the manufacturing equipment worked, and how the process varied from day to day. Nicholas credits Friendly''s employees with being willing to help, from documenting daily occurrences to brainstorming on where exactly the problem might lie. Together they learned that teamwork can go hand-in-hand with technology.

Nicholas worked on the puzzle using a series of sophisticated mathematical techniques taught by Seiford. (Nicholas received her bachelor''s degree in electrical engineering from the University in 1981). While Nicholas gained valuable professional experience in this area, Friendly’s saw the project as an opportunity to invest time and energy in creating an even better product for its customers.

"They were open and willing to go on these journeys; these mathematical tools are great, but you can''t solve the problem without a team," Nicholas said. AIt really involved an attitude and willingness to see things differently."

She created a series of computer software files using statistical process control (SPC), which evaluates the amount of variation in the manufacturing process. "The implementation of an on-line SPC system enabled us for the first time to really assess the variation in the system," Nicholas said. It was this knowledge that encouraged her to use another mathematical tool called Design of Experiments, or DOE, which characterizes and quantifies the causes of the variation.

"U.S. manufacturing can use these tools to help solve real problems in industry," Nicholas says. "SPC and DOE can help improve quality, which is important because it''s a very competitive marketplace out there."

The variations revealed by SPC - which can be costly and difficult to manage - were challenging. So Nicholas went on to use DOE, which reveals which of the variable factors is most significant. Nicholas and the workers at Friendly''s focused on five variables, including air pressure and the refrigeration system.

The sophistication of DOE cuts down on experimentation time radically, and it allowed Nicholas to learn in just 16 experiments what, under old-fashioned methods, would have taken more than 32,000 experiments.

Results pointed to the air pressure system as being critical: "By the end, we could really characterize everything in terms of its impact on the final weight," says Nicholas, Aand no other factor influenced the product''s final weight as much as air pressure."

Understanding the source of the variation, she then went on to build a mathematical model called RSM (Response Surface Methodology), which defines the critical relationships. AAfter applying these mathematical tools, we have a more stable process, improved process yields, and reduced variation in the system," she said. "The key point was Cher''s technical skill and dedication," said Gathro, of Friendly''s. "The air-pressure problem was very subtle." Nicholas''s master’s project had only entailed bringing SPC to the manufacturing process, Gathro said, A but once she found that a problem existed, she chose to pursue the application of these other mathematical tools." The company addressed the situation by installing SPC computer terminals right on the production floor, so that ice cream makers can monitor the process closely, and make quick adjustments as needed.

Nicholas graduated in May and began working at Tambrands, in Palmer, where she is also helping to develop manufacturing processes and products using mathematical tools.