Warning issued on traditional pickling

Nine deaths serve as reminder of food safety issues

Nine members of a family in Heilongjiang province died last month after they ate homemade suantangzi, a type of thick noodles made from fermented corn flour.

In a case that made headlines, the National Health Commission said the fatalities, which occurred in Jidong county, were caused by bongkrek acid, a respiratory toxin produced by a bacterium that contaminated the noodles.

In summer and autumn, fermented food made of rice or flour is susceptible to contamination from the bacteria, which can survive even when the food is boiled at a high temperature.

There is no specific antidote and the fatality rate from such infections can exceed 50 percent.

The commission warned the public against making or eating such foods, which include fermented glutinous rice dumplings and fermented rice noodles.

It said 14 bongkrek acid poisoning cases had been reported in China since 2010, resulting in 37 deaths and involving 84 people.

Flour and rice are not the only staples fermented in the nation's households. From vegetables to meat, Chinese have shown their creativity in making a variety of fermented and pickled foods, a tradition that is more than 2,000 years old.

In addition to preserving many different foods for long periods of time, pickling can bring out unique flavors.

Whether served as a side dish accompanying porridge or noodle soup, or used as a condiment for stewed fish or boiled meat, pickled food is an essential part of the Chinese daily diet.

In different areas, people use contrasting ingredients and methods to make this food. Common ingredients include cabbages, cucumbers, radishes, ginger and garlic, as well as proteins.

In northern areas of China, pickled food is usually marinated with a high salt content, while in the south, it is traditionally fermented with a low salt content and lactic acid bacteria.

In the northeast, after napa cabbage is harvested in late autumn, families begin to make pickled cabbage.

The cabbage is dried in the sun for two days. It is then cleaned, the outer leaves are removed and the base is cut off.

Jars used to ferment the cabbage should be thoroughly clean and dry.

Salt is placed in the bottom of the jars before a layer of cabbage is added. Alternate layers of salt and cabbage follow until the jars are full.

A heavy stone is then placed on the cabbage layer at the top. After several hours, water is added until the jars are full again.

The pickled cabbage is usually ready to eat after a month. The amount of cabbage and salt used is key to this dish, while each family has its own recipe.