GRAND RAPIDS, Mich. (WOOD) — What is your opinion of Blue Moon? It’s a question that only Michiganders and a handful of others will actually understand.

Not the beer. Not the rare celestial event. To quote the kids, it’s ice cream! And it’s found almost exclusively in Michigan and Wisconsin, as well as pockets of Indiana and Illinois.

Blue Moon ice cream is known for its delicious yet hard-to-pin down flavor and its bright blue coloring. But how could a treat so beloved in one state have so small an audience outside of the Upper Midwest? That’s just one of the mysteries of Blue Moon ice cream.

MYSTERY NO. 1: WHAT FLAVOR IS IT?

Everyone has their own opinion, but the actual answer is locked away.

Some people say almond or marzipan. Others say marshmallow or vanilla mixed with citrus. My wife says nutmeg. My favorite response so far is just “blue.” And all of those answers make sense. The ice cream has a bizarrely bold flavor that hits different notes.

The actual flavoring recipe is considered proprietary information and is held by Weber Flavors in Illinois. A writer for Atlas Obscura spoke to Weber Flavors Vice President James Doig back in 2021.

“I have the formula here in front of me,” Doig told Atlas Obscura. “But I’m not going to tell you what’s in it.”

Weber did not respond to several requests for comment from News 8.

While Weber has the patent to Blue Moon, it’s not the only flavor maker in the game. There are plenty of companies that offer their own take on the Midwestern classic. And with each different formula, you get slightly different flavors, adding new variables to the equation.

There are plenty of theories out there, but none stranger than one presented by an old Wisconsin news outlet in 2007. They surmised that castoreum could be the secret ingredient behind Blue Moon. Castoreum, an oil that is excreted from scent glands in beavers and platypuses. It has a strong, displeasing odor but can also be used to accentuate flavors. Castoreum is approved for use by the FDA and isn’t generally listed as an ingredient because it is covered by the catch-all term of “natural flavorings.”

I don’t know about you, but I’m rooting against that one.

MYSTERY NO. 2: WHO INVENTED BLUE MOON ICE CREAM?

Another great question! We don’t really know.

According to Nara Schoenberg, who investigated the ice cream’s origins for the Chicago Tribune in 2007, there are two prevailing theories, but both have their holes.

One is called the Michigan theory, which credits Sherman Dairy Products in South Haven with being the originator. If there was a chance that was true, you’d think the family company would stake its name to it. But they don’t. At the time, they told Schoenberg that they got their Blue Moon flavoring from an outside company. Blue Moon was also reportedly around before Sherman’s started selling ice cream in the 1950s.

The other is the Milwaukee theory. That story centers on Bill “Doc” Sidon, a Jewish chemist who fled Austria in 1939 and found work at Petran Products in Milwaukee in the 1950s.

According to Atlas Obscura, Weber Flavors eventually absorbed Petran Products and Doig believes Sidon invented Blue Moon while with Petran. That makes sense considering Weber holds the patent. But Schoenberg found plenty of evidence that conflicts with that.

For one, Petran’s paperwork with the U.S. Patent and Trademark Office claims that Petran was using Blue Moon-branded flavoring as early as 1939, before Sidon had even left Europe, let alone made his way to Petran.

Secondly, Sidon’s own daughter knew nothing about it. Nancy Smuckler told Schoenberg in 2007 that Sidon never mentioned inventing Blue Moon, though she also noted he wasn’t one to brag.

Finally, some evidence with a hard time stamp: Schoenberg’s contemporaries at the Tribune found advertisements in their own newspaper from the 1930s promoting Blue Moon ice cream. So while Petran may still be involved, it’s highly unlikely Sidon played a role.

Then there’s a third theory — one that doesn’t have a ton of evidence but also doesn’t have much to dismiss: Ludington’s own House of Flavors.

News 8 spoke with Barry Neal, the third-generation owner of the family business. Neal confirmed that his family bought Miller Dairy in 1948. At the time of the takeover, the company manufactured five flavors of ice cream, including Blue Moon.

“I had a man actually come into the restaurant who had Blue Moon at other places. He said, ‘You know, it’s so sweet.’ But he’s here and he said, ‘This didn’t taste like what I expected. It’s really mild.’ I think that’s the original Blue Moon. It’s a very creamy, mild, sweet flavor,” Neal told News 8.

Was that history — or at least the desire to take credit — lost when the Miller family sold the company? It’s possible.

Neal admitted that he doesn’t know much about the flavoring process and couldn’t get into specifics about how House of Flavors manufactures its Blue Moon ice cream, but said he knows it has always played a prominent role in the company’s branding, including their mascot, Mr. Moonie.

“There are certain things that you come to expect (from a business), and they are always here. Blue Moon is an ice cream flavor that we don’t ever take off (the 42-flavor rotation),” Neal said. “It’s part of the foundation that we are built on.”

Still, not enough evidence to prove one way or the other.

MYSTERY NO. 3: WHY IS IT BLUE?

Another valid question with no real answer. Barry Neal has a theory that makes a lot of sense. He thinks Blue Moon may have been made to target kids.

“Our first flavors were vanilla, chocolate, lemon and French vanilla. There’s probably not a child that’s going to naturally order lemon or French vanilla or vanilla. That sort of left them with that blue ice cream or chocolate to order,” Neal said.

For people who think Blue Moon includes berry flavoring or cotton candy, a blue hue would make some sense. But if not, why blue?

Well, why not? If nutmeg is the secret behind Blue Moon, you can’t make it brown. It would be confused for chocolate ice cream. What about citrus? Yellow could be confused for lemon or even vanilla. Anything with a greenish hue could be mistaken for mint or pistachio.

Maybe Blue Moon is blue because there weren’t many other options?

It’s a mystery you can think about next time you grab a cone or enjoy a scoop of ice cream.