Winter is coming. Who can resist some steamy hot cured meat claypot rice or flavourful instant noodles with ham and sausages?
Before indulging in these mouth-watering dishes, be reminded that processed meat is not just high in sodium and fat, but also nitrate and nitrite, which are converted into N-nitroso compounds (NOCs), substances that are classified as Group 1 carcinogens by the International Agency for Research on Cancer (IARC) under World Health Organization (WHO).
Nitrate can be naturally found in a lot of vegetables and fruits. During processing, however, nitrate and nitrite are artificially added as preservatives to keep the fresh appearance and taste of processed meat.
Nitrate itself is not poisonous, but its metabolite, nitrite, is bad for health. The amine in food reacts with nitrite to form N-nitroso compounds such as nitrosamine which is proven to be carcinogenic. That said, a person who consumes cured meat frequently is at higher risk of cancer.
Apart from cured meat, nuts and dried goods also contain a carcinogen, a toxic secondary metabolite (mycotoxin) called aflatoxin.
Food products that are not stored properly will be easily contaminated by aflatoxin and produce toxins. Examples include peanuts, seeds, corn and other grains. The aflatoxin in them cannot be destroyed by high heat so it is especially important to purchase vacuum packed food products from reputable retailers. Dry goods should be stored in cool places before they get moldy. Toss them immediately when they pass their expiry dates.
The Centre for Food Safety has recently tested 140 cured meat samples for their chemical and nutrition content. Fortunately, they have all passed the test. Even so, it is not recommended to consume a large amount of cured meat regularly.
Choose handmade cured food products wisely because they are not monitored and the amount of their additives is unknown.
Cooking methods do matter. Always make sure the ingredients are thoroughly cooked. Frying or barbecuing produces carcinogens. Consider broiling, boiling or steaming instead to minimize carcinogens.
This article appeared in the Hong Kong Economic Journal on Nov. 28
Translation by John Chui
[Chinese version 中文版]