Pictures of company executives bowing their heads deep in apology have become near-daily fare on TV news programmes in recent days, rattling consumers who had been more worried about imports from China and a long-running row over US beef.
Before Mister Donut, operated in Japan by Duskin Co Ltd, confectionary maker Akafuku Co was found to have fudged production and expiry dates for its bean paste-covered rice cakes for over 30 years.
A confectioner selling a similar product, which saw sales sky-rocket after Akafuku's scandal, has now been reported to have extended expiration dates for its sweets and printed false ingredient tables.
The scandals, which industry watchers say have come to light from whistle-blowers, have angered consumer groups, who blame companies for duping customers in pursuit of easy profits.
There have been no recent reports consumers falling ill from the mislabelled goods, but food scares have nonetheless dismayed the public, in a land where elaborately packaged food is often given as a gift.
In 2000, more than 10,000 people suffered food poisoning after drinking tainted milk made by Snow Brand Milk Products at a plant that was later found to have violated hygiene standards.
The government would improve oversight of companies and continue releasing the names of the companies at fault, an official said, but he added there were no plans for stricter punishment, which now include fines after two warnings to correct false labelling.
"Making public the company name alone hurts the company's credibility and can help prevent the mislabelling from occurring again," said Masaya Nakamura, an official at the labelling and standards division at the Farm Ministry.
In another high-profile case, Fujiya Co Ltd admitted in January it had shipped cream puffs and other products made with stale ingredients, tarnishing its image as the children's cake maker.
In August, media went into a frenzy after a sweets maker in the northern island of Hokkaido was found to have mislabelled expiry dates for chocolate cookies popular with tourists.