The construction of a food safety system for metal packaging is a systematic project

Theoretically, with technological advancements, the competitiveness of three-piece (3pc) and two-piece (DWI and DRD) tinplate cans for both food and beverage packaging is constantly changing.

The safety of metal packaging is a serious issue, involving many aspects—from government regulations and supervision, industry association guidance, and technological advancements in the metal packaging and related industries, to the reverse influence of food and beverage manufacturers.  It requires the concerted efforts of all parties to complete this systematic project involving food safety.

Drawing on Japan's experience, there is still an opportunity for the Chinese metal packaging industry to replace coated tinplate three-piece cans with laminated tinplate three-piece cans. Besides three-piece cans, the application of laminated tinplate also needs to overcome two major challenges caused by severe stretching and deformation: first, thin-walled drawn two-piece cans, where the deformation exceeds 70%; and second, easy-open lids, where the deformation at the rivet position is around 55%. Resisting deformation and ensuring the quality of the empty cans after use still hinges on the quality of the tinplate base material itself. When using laminated tinplate, it is important to consider its compatibility with the contents. Without this knowledge, directly using laminated or coated tinplate for can manufacturing without other remedial measures, such as adding appropriate amounts of food-grade stannous citrate, will certainly lead to a loss of the product's commercial value.

In the beverage can sector, although the two major herbal tea brands drove the "three-to-two" can conversion trend in recent years, two-piece cans have yet to gain a foothold in the Chinese market for the packaging of sensitive protein and dairy beverages. Only hot-filled three-piece cans, aseptically filled PET bottles, and paper-aluminum-plastic composite packaging (commonly known as Tetra Pak) are seen.

In terms of both technology and cost, tinplate material is fundamental to the can manufacturing industry. Generally, tinplate accounts for up to 70% of the can manufacturing cost, and material thinning is of great significance in saving can manufacturing costs.

There are numerous indicators for evaluating coatings, and Japan's control over the safety of internal coatings is worth learning from and emulating by the Chinese can manufacturing industry. Although national standards are largely similar worldwide, Japan's industry standards are higher than its national standards, and corporate standards are even higher than industry standards. This has resulted in Japan's canned food safety standards being considered among the best in the world.

The construction of a food safety system for metal packaging is a systematic project. Given China's national conditions, government departments, including those responsible for supervision and the formulation of regulations and standards, will play a leading role. These departments can learn from and draw on Japan's practices, and strengthen their awareness and knowledge in this area.

Currently, many large food and beverage brands have established their own quality inspection standards and monitoring systems, equipped with high-end testing instruments to monitor the necessary data. They generally hope that food safety can be achieved in one step when there are no technical obstacles. This driving force has greatly promoted the progress of the upstream can manufacturing and coating industries. The chairman of a famous beverage manufacturer once divided domestic enterprises into three categories: the first category includes enterprises willing to assume social responsibility and are striving to or have already aligned with world-class standards; the second category includes enterprises that follow existing national standards; and the third category includes enterprises that only care about making money without any ethical bottom line. It can be said that only when the first category of enterprises becomes the mainstream will food safety cease to be a problem.

Although current food safety in domestic metal cans faces many problems, technological progress will undoubtedly bring about innovation. Besides strength and capital investment, the people involved, the methods used, and the determination to succeed are even more important for the success of a project.