On June 2, 2026, Taiwan media UDN (United Daily News) reported, "When a certain Taiwanese woman returned from her trip to Japan, she noticed many people buying a particular souvenir at Fukuoka Airport. When she posted on SNS that some people were buying more than 20 of these items, it received a great response from many netizens."

According to a post by a Taiwanese netizen on SNS Threads, when returning from Fukuoka Airport, she saw many tourists buying large quantities of Yamaya's "Mentaiko France." Mentaiko France is a product featuring a generous filling of Yamaya's karashi mentaiko (spicy pollack roe) in a special bread made with a blend of rye and stone-ground flour, and is sold for approximately 80 New Taiwan Dollars (about 400 yen) per piece. It is a popular product in Fukuoka, sometimes selling 1,000 pieces a day, and the woman who posted also bought a box of 5 as a souvenir, which turned out to be very popular.

In response to this post, other netizens commented: "You absolutely must buy Mentaiko France at Fukuoka Airport," "I also bought it when I went last time," "It's truly delicious," "I bought 4, but I should have bought more," "I go to buy it every time I visit Japan, but it's always sold out," and "When you return to Taiwan and warm it slightly in a toaster, the aroma comes out and it becomes even more delicious."