Why are frozen berries linked to hepatitis A? Can frozen fruits still be eaten? Nutritionists say...

The Food and Drug Administration recently announced that Costco’s frozen berries were being removed from the shelves for recall, which really scared many people. How many people have eaten the 17,000 kilograms (about 9,392 bags) of frozen berries that may have been contaminated with the hepatitis A virus? Will there be any vulnerable children, elderly people or people with compromised immune systems among them? Can I still eat frozen berries in the future? These issues of food safety and choice seem to have become a concern for every household and caterer.

There are precedents for ready-to-eat fruit contamination incidents internationally.

How did hepatitis A get into packaged frozen berries? Nutritionist Lin Ya-en, chairman of the Taiwan Health and Nutrition Education Promotion Association, said that this is not the first time that similar food safety issues have occurred. There was a precedent as early as 2013. At that time, Costco in the United States sold frozen berry combination packs from Townsend Farms, infecting at least 162 people with the hepatitis A virus. An investigation at the time found that the contaminated guava seeds in the fruit combo packs came from Türkiye. In the same year, at least 1,444 people in Europe were infected with the hepatitis A virus after eating frozen berry combo packs.

This food contamination and removal incident originated at the end of last year in 2022. Because many people in the United States and New Zealand reported being infected with hepatitis A at the same time, the relevant authorities took it seriously and launched an investigation. They discovered that the culprit was frozen berry packs, and most of them came from the same supplier mentioned above.

Two key contamination pathways for packaged food

According to the historical incidents of packaged food contamination investigated in the United States and New Zealand, whether it is apple juice contaminated with E. coli or frozen berries with hepatitis A virus, most of them enter packaged foods through two ways:

1. Poor hygiene management of food processing plant personnel:

Hepatitis A virus exists in the excrement of infected individuals. If employees on the food production line do not maintain personal hygiene such as washing hands after using the toilet, changing gloves and masks frequently, or if the production factory has poor environmental control, mosquitoes, flies and insects will become carriers of bacteria and viruses, which can easily contaminate the food on the production line.

2. Water source issues for irrigation or washing food crops:

Water source management upstream and downstream of food factories often poses a concern for health and safety. For example, the E. coli-tainted apple juice incident in the United States many years ago was caused by contamination from wastewater from cattle farms upstream of the processing plant.

The control process of a food factory is no more complicated than rocket science in terms of logic. However, the food ecological chain from the place of production to the table has become increasingly complex in the past 20 years. A package of frozen berries delivered to consumers may have grown in a farm in Chile or Canada, been packaged in the United States, and then shipped to Mexico for frozen packaging. Then, it passes through transshipment stations around the world, and the wholesale packaging becomes shipping packaging and then becomes consumer-friendly packaging. It goes through several countries, dozens of processing plants, processing plants, packaging plants, centralized dispatch plants, and the hands of countless workers. The result of such convenient global transportation has also greatly increased the sanitary risks of food safety.

Nutritionist Lin Yaen said that whether frozen fruits can be eaten in the future actually depends on whether you and I can be more proactive in requiring manufacturers to provide food traceability information, be better able to distinguish the reputation and quality control of food manufacturers' brands, and be more able to choose catering and food companies that care about safety and sustainability.

Can frozen fruits still be eaten?

Many people will ask, won’t the freezing temperature kill viruses or bacteria if it is so low? Nutritionist Lin Yaen said that from a microbiological point of view, in order to kill most pathogens, it is necessary to heat the food to at least 60 degrees Celsius. However, keeping the temperature below 5 degrees Celsius can only make the bacteria inactivated, that is, make them dormant and ineffective. Once the temperature rises back to between 5 and 60 degrees Celsius, the germs will become activated again, posing a risk of infection.

This food safety incident has given us a lot of reflection. In addition to clearing away the impression that "imported goods are not necessarily the best choice", it has also reminded us once again of the importance of washing hands frequently, understanding food traceability, and knowing how to see "where food comes from". Berry foods do have their unique nutritional value, but when it comes to ensuring the hygienic safety of food sources and processing, as consumers we also need to pay more attention to these processes and play a smart role in supervision and advocacy.

Nutritionist Lin Yaen said that whether frozen fruits can be eaten in the future actually depends on whether you and I can be more proactive in requiring manufacturers to provide food traceability information, be better able to distinguish the reputation and quality control of food manufacturers' brands, and be more able to choose catering and food companies that care about safety and sustainability. There is a three-chapter-one-Q mechanism in China to help consumers make basic judgments, but how do we distinguish imported food? These may be the issues that you and I as consumers need to be concerned about, so that we can gradually eliminate the substandard food products through market mechanisms.

Food safety crisis can lead to food and agriculture education issues

Provide food and agriculture education personnel with a platform to discuss food and agriculture education issues through this food safety incident. Let us guide everyone to pay more attention to food and agriculture education from the perspective of food and the global supply chain.

A. Production and environment: processing safety, environmental cross-infection, and carbon footprint of imported packaged food.

B. Health and consumption: How to prevent and treat hepatitis A through diet, and food hygiene and safety.

C_Culture and Habits: The various ways Taiwanese people eat berries.