Canned food is not actually "junk food"; it's been misunderstood.

Mentioning canned food, many people associate it with “high in preservatives” due to its long shelf life and ready-to-eat nature, even thinking it is less healthy than fresh ingredients. Indeed, canned food often has a long shelf life, even up to three to five years, which leads many to label it as “junk food.” But is that really the case? In fact, canned food is truly misunderstood.

Canned food not only extends the preservation time of food while retaining its nutritional value, but in some cases, it even offers advantages over fresh food. Its “preservation secret” does not rely on preservatives, but rather on unique processing techniques and sealing technology.

China has been the world's largest producer and exporter of canned food for many years, with its output accounting for about a quarter of the global total. However, various misconceptions about canned food still persist. Today, let's uncover the truth and give canned food a fair evaluation.

Canned food really has no “preservatives”

Because they're simply not needed

GB 2760-2024 “National Food Safety Standard for Uses of Food Additives” officially came into effect on February 8, 2025, which explicitly stipulates that preservatives shall not be used in canned foods. This policy not only marks a leap forward in China’s food industry technology but also shatters the long-standing misconception about canned food’s “reliance on preservatives.”

According to the “National Economic Industry Classification and Code” formulated by the National Bureau of Statistics, canned products are mainly divided into meat and poultry cans, aquatic product cans, fruit and vegetable cans, and other canned foods. They all share one common characteristic: a very long shelf life, mostly 2-3 years.

Actually, this is not surprising, after all, the original intention behind the invention of canned food was to extend food shelf life.

With technology advancing today, the production and processing of canned food have also become increasingly modernized. The secret to long-term preservation without added preservatives lies in the production process.

GB 7098-2015 “National Food Safety Standard for Canned Foods” stipulates that canned food is a commercially sterile canned product made from raw materials such as fruits, vegetables, edible fungi, livestock and poultry meat, and aquatic animals, processed through steps such as processing, canning, sealing, and heat sterilization. Semi-finished products after canning and sealing must be sterilized within 2 hours. The current mainstream method is heat sterilization, which, by adjusting time and temperature, achieves commercial sterility while maximizing the retention of the food’s nutritional components. It is generally divided into two types: low-temperature sterilization and high-temperature sterilization.

·Low-temperature sterilization is 80~100℃, also known as atmospheric pressure sterilization, with a duration of 10~30 minutes, suitable for fruit cans and some vegetable cans with higher acidity (pH below 4.6). For example, canned yellow peaches, canned pineapples, and canned mandarins, which can keep the fruit intact and taste close to fresh fruit; pickled cucumber cans and tomato paste cans also require low-temperature sterilization.

·High-temperature sterilization is 105~121℃, also known as high-pressure sterilization, with a duration of 20~90 minutes, suitable for meat, aquatic products, and most vegetable cans with lower acidity (pH above 4.6) and non-acidic properties. For example, canned luncheon meat, braised pork cans, and sardine cans; sweet corn cans, green bean cans, and chickpea cans also undergo high-temperature sterilization, which softens the food texture while retaining complete dietary fiber.

With the development of food processing technology, new techniques such as modified atmosphere sterilization and microwave sterilization have emerged. These methods offer shorter sterilization times and better results, which are more beneficial for preserving the food’s original color, flavor, and nutrition.

After such sterilization treatment, microorganisms have no chance of survival. After high-temperature sterilization, it also needs to be cooled below 40℃, at which point a negative pressure forms inside the container, and the lid seals more tightly, making it difficult to open. Throughout this entire process, no microorganisms survive inside the can, and external microorganisms cannot enter, thus eliminating the need for preservatives.