The Berkey Creamery at Pennsylvania State University was at full throttle on a recent Friday morning.

The Nittany Lions were playing Rutgers the next day - the second of five home football games in a row, something that hasn't happened in nearly a century. That means an extraordinarily high demand for "Peachy Paterno," "Alumni Swirl," and other frozen flavors distinctive to the oldest collegiate creamery in the United States, celebrating its 150th anniversary this year.

On a usual day, the store serves 2,500 customers. On home football weekends, the number jumps to 6,000 to 10,000, said Tom Palchak, creamery manager. Beautiful weather pushes numbers to the higher side. This fall, imagine that five weeks in a row.

"We started to ramp up the inventory a full month before the first game," Palchak said.

"It's controlled chaos," said supervisor Susan Maureen Watson, 54, a longtime employee.

The creamery expects to churn out 350,000 gallons of ice cream this year, a record - up from 250,000 in 2014, Palchak said. Much of the increase is due to the publicity around the anniversary, for which the creamery produced a new flavor: "Birthday Bash," a birthday cake ice cream.

Berkey is one of 21 collegiate creameries in the U.S. They are most common among the nation's land-grant universities, like Penn State, which historically have been big on agricultural programs.

At one time, there were more creameries. Now, the only other one in the region is at the University of Delaware, and it is relatively new.

"We do well because we're in a very populated area," said Melinda Litvinas, creamery operations manager at Delaware and past president of the national University Creamery Managers Association.

"Penn State does well because it has the largest alumni base in the country. Some schools don't have the population to keep it going and bring in the business."

The idea for a creamery at Delaware came from a group of students in 2008 and it opened in 2011. It also operates an ice cream truck, the Moo Mobile, the only collegiate creamery with a mobile truck. Its signature flavor: Delaware River Mud Pie - vanilla and chocolate cookie ice cream with fudge swirls.

The university is raising money to build a larger facility and processing plant, Litvinas said. It currently sends its milk to an outside dairy plant to be processed into ice cream. The university creamery then freezes it and packages it in-house, she said.

Proceeds from the creameries, Litvinas said, help subsidize research and teaching programs and give students a chance for hands-on experience in sales, marketing, and processing.

Cornell and the University of Maryland house the next-closest collegiate creameries. The University of Wisconsin, the University of Nebraska-Lincoln, Kansas State, and Michigan State are among other schools in the business. About half of the creameries also make cheese. A handful do yogurt. Most bottle milk, too.

Penn State's creamery, with 24 full-time employees and 90 student workers, does everything, including iced tea and lemonade. But it's best known for its ice cream. The creamery rotates about 150 flavors in its store, with about 30 available at any time, and with special seasonal offerings. "Mallo Cup," "Apple Cobbler Crunch," "Pumpkin Pie," "LionS'more," and "Monster Mash" are big in fall.

Some flavors are the result of naming contests. Named after football coach Joe Paterno, "Peachy Paterno" was introduced in 1989, chosen from more than 1,000 names. Paterno's wife, Sue, picked "Peachy Paterno," Palchak said. The recipe includes a nectarine puree and, believe it or not, actual peach schnapps.

Despite the Jerry Sandusky child sex-abuse scandal that cost the late Paterno his job, the flavor remains among the top five most popular, Palchak said. The others are vanilla, death by chocolate, butter pecan, and bittersweet mint, a mint chocolate chip. But some flavors fail. The biggest disaster was carrot cake, Palchak said. The recipe had real pieces of carrot.

"That just did not go over," Palchak said. "I made 300 half-gallons and 50 tubs. I probably threw away 49.5 tubs and 280 half-gallons."

"Sandusky Blitz," named after the former defensive assistant football coach, had been successful, but was removed after the scandal broke, he said.

The creamery can boast of many famous customers, including Teresa Heinz Kerry, Martha Stewart, Coretta Scott King, and Sarah Palin. Former President Bill Clinton to this day is the only person ever allowed to mix flavors. Because of the high volume of customers, only one flavor is allowed per order. But Clinton was granted his desired mix: a "Peachy Paterno" and "Cherry Quist" cone.

The creamery also teaches others how to make ice cream. Ben Cohen and Jerry Greenfield of Ben & Jerry's fame took a Penn State correspondence course. Now, the university's weeklong ice cream short course, held the first week of January, attracts aspiring creamery operators from all over the world. The 150-student class for 2016 has been sold out since August, and there's a waiting list of 60 for the 2017 course, Palchak said.

The creamery got its start in a barn in 1865, producing butter and cheese for students who lived on campus. It survived two world wars and two depressions, was there for the introduction of refrigeration, and kept up with Penn State's rapid expansion. Berkey now is housed in the university's $48 million food science building.

The creamery got its name about a decade ago after Earl Berkey, a Somerset County butter plant operator, wrote a check for $3 million for naming rights.

The creamery used to give tours to the public but stopped after 9/11 because of security concerns. However, media tours are still allowed. Palchak took an Inquirer reporter and photographer on one that included the minus-35 degree "hardening room."

The ice cream stays in there at least 24 hours to get out any water, which can cause an iciness unpleasing to the palate.

"Now, we're going to warm up here; this is a balmy minus-25 degrees," Palchak said as he walked into a storage room stacked to the ceiling with ice cream.

"Most of this will be gone on Monday morning," he said. "All these racks will be emptied out and refilled for the next home game."

In the ice cream store, several patrons were enjoying ice cream cones though it wasn't even noon.

"This is so good, I think we're going to come back here after lunch, before we head back home," said Rob Gaetano, 50, an optometrist from Canfield, Ohio, who was touring the school with his wife and son, a high school senior.

Lauren Kirch, 22, a senior petroleum and natural gas major from Houston, is a regular, who that morning was enjoying "Apple Cobbler Crunch." She couldn't even compare her school's ice cream to other kinds: "If you're going to get ice cream," she said, "you need to come to the creamery."