Kim Dong-seon's Burger Losing Its Charm vs Fresh 'Big Mac' [Spoiling Burgers]③

6 Hamburger Franchise Decay Experiment
3rd Week Status Recheck After October 7
Five Guys and Burger King Covered in Mold

Amidst a spectacle of blue and white mold spreading thickly, only two hamburgers remained vividly intact. The protagonists were none other than McDonald's Big Mac and Lotteria Bulgogi Burger.

The Asia Economy Food & Beverage Team has been observing the signature burgers from six hamburger chains?McDonald's, Mom's Touch, Lotteria, Burger King, KFC, and Five Guys?left at room temperature for three weeks. Most of the hamburgers showed rapid decay.

Five Guys Covered in Blue Mold

The condition of the Five Guys Bacon Cheeseburger after 3 weeks since starting the hamburger rotting experiment.

The fastest decaying hamburger was Five Guys' Bacon Cheeseburger. From the 7th day, one week into the experiment, white mold appeared on the bun, beef patty, and tomato, and the cheese began to melt, marking the earliest visible changes.

As of the 28th, the top of the bun was covered in blue mold. By the second week, the bun was still more visible than the mold, but now over 70% of the surface was covered in mold. The mold's form also changed. The fluffy mold started clumping due to moisture inside the container, making the appearance hard to recognize. On the meat patty, large gray mold patches resembling clouds appeared, creating a vivid display of blue, white, and pale mold colors. Interestingly, the melted cheese that had dripped remained intact.

'Mold Powder' Sprinkled Burger King Whopper... Accelerated Decay

The condition of the Burger King Whopper after 3 weeks since starting the hamburger rotting experiment.

By the second week, following the Bacon Cheeseburger, the most noticeably decayed products were KFC's Zinger Burger, which uses chicken patties, and Mom's Touch's Cyburger. However, the rankings shifted. Burger King's Whopper, which showed little change during the first week, developed mold for the first time in the second week, and now the top of the bun was completely covered in white mold. It looked as if sugar powder had been sprinkled, with mold growing densely without gaps. Moisture gradually accumulated, and droplets began forming on the plastic container. Looking at the bottom of the bun, moisture and mold had formed between the bun's folds. Since the bun had shrunk and covered the patty and vegetables, the interior could not be checked, but there was no sign of mold between the buns.

With the rankings reversed, Burger King's advertisement naturally came to mind. In 2020, Burger King USA released a 45-second global commercial on its official YouTube channel showing a Whopper covered in mold after 34 days. The English tagline "The beauty of no artificial preservatives" emphasized that the Whopper was made with eco-friendly ingredients. In the video, after 34 days, the entire burger?including the bun, vegetables, and patty?was covered in dark blue mold. Asia Economy plans to directly compare the Whopper's appearance on the 34th day of the experiment, next month on the 9th, with the Whopper shown in the advertisement.

After 3 weeks of the hamburger rotting experiment, the state of Mom's Touch Cyburger (left) and KFC Zinger Burger (right).

The Cyburger looked similar to its state in the second week. However, the dark blue mold on the bun and chicken patty grew larger like a mushroom-shaped atomic bomb. The inside of the experimental container was filled with moisture, and droplets were dripping. The Zinger Burger maintained almost the same appearance. Mold, which had concentrated on the chicken patty, spread to the bun, but one side was particularly badly spoiled while the other side still clearly showed the chicken surface, maintaining its original form.

McDonald's Big Mac Retains Its Volume... Will It Prove 'Hamburgers Don't Rot'?

Condition of McDonald's Big Mac (left) and Lotteria Bulgogi Burger (right) after 3 weeks since the hamburger decay experiment began.

The so-called "immortal" McDonald's Big Mac and Lotteria Bulgogi Burger still showed slow external changes. The Big Mac bun's volume was surprisingly maintained, and unlike other products, no moisture formed on the container walls. It seemed to remain dry. On the 8th day of the experiment, a small white mold about the size of a fingernail appeared on the lower patty and bun, and it remained the same.

If this continues, the rumor that "hamburgers don't rot" might not be baseless. The Bulgogi Burger showed no significant visual changes from the second week, although small mold spots on the patty edges had spread to the bun. Lotteria's Bulgogi Burger showed decay spreading mainly on the bun touching the plastic bottom. However, the patty and the top bun still maintained the hamburger's appearance as in the early stages of the experiment.

Regarding these experimental results, a representative from FG Korea, which operates Five Guys in Korea, said, "The daily supply of fresh ingredients such as vegetables and the absence of freezers in the kitchen seem to have greatly influenced the speed of hamburger decay," adding, "We will continue to focus on the freshness of ingredients and food hygiene management."

As the hamburger decay experiment enters its third week, the studio's temperature ranged from 16 to 22 degrees Celsius, and humidity ranged from 37% to 84%. Asia Economy will continue to observe under the same conditions which hamburger visually resists decay the longest.