Bullet trains in China will increase the supply of fresh meals whose shelf-life is no longer than 72 hours, Beijing Morning Post reported.

The decision follows the public’s criticism that meals sold on bullet trains have a 6-month long shelf life, suggesting the use of preservatives in the food. The Ministry of Railways has insisted meals with longer shelf-lives are also safe.

This would be similar to the meals offered by airlines to passengers on flights.

Bullet train food became a hot topic earlier this month after a passenger complained online that meal box labeling showed a six-month shelf life.

This post led to online debate over fears that the meals may be unsafe and contain high levels of preservatives.

Railway authorities sought to reassure passengers that the vacuum-packed food is safe and providers are licensed.

But now the ministry has said food on sale should have a shelf life of less than 72 hours. Chilled meals will now be offered on an everyday basis, with vacuum-packed food used as emergency back-up.

Operators are also considering other options, such as buying in hot meals along the route.

Snacks on offer on high-speed trains are also viewed as having too long a shelf life. Fried dough sold at breakfast time can be stored frozen for 10 months.

And some passengers are unimpressed by the taste of long-life fare.

"The food didn't have much flavor and was hard to chew," complained one traveler online.

But producers stressed that their food is safe. "We introduced processes similar to canned food production," said a manager with one producer, Zhejiang Tonglu Guanhua food company.

The company has been providing food for bullet trains since 2009 and checks are strict, said the official.

Academics agreed with the food producers.

Based on current technology, it's possible to make freshly cooked dishes and rice preserve for longer than six months, Fan Zhihong, an associate professor of Institute of Nutrition and Food Safety of China Agricultural University told the media.

The food is sterilized and can last for a long period without preservatives, said Fan.

The ministry has also asked for less expensive meal options to be offered.

(Shanghai Daily contributed to this story)