What Are The Advantages And Uses Of Tinplate Boxes

The Shift to Tinplate Box Packaging: Why Merchants Are Making the Switch

Have you noticed that whether you visit a large mall or a small store, the first thing you see is chewing gum? These gums have evolved from paper packaging to plastic boxes and now to the popular tin box packaging favored by many merchants. But what has led to this choice? What are the benefits of tin box packaging? Let's explore these questions by understanding what tinplate is.

 What is Tinplate?

Tinplate is an iron-tin alloy with tin as the coating. It is primarily used in the production of food packaging boxes and cans because it combines the strength and formability of steel with the corrosion resistance, solderability, and aesthetic appearance of tin. This material is characterized by its corrosion resistance, non-toxicity, high strength, and good ductility.

Tinplate is classified based on thickness and tin plating quantity. Generally, to save costs, industrial production aims to reduce the thickness of iron and the amount of tin plating while ensuring the reliability and strength of the packaging.

1. Reduced Tin Usage**: The industry has moved from hot-dip tinplate in the 1950s to electroplated tinplate, and now hot-dip tinplate is no longer used in can making in China.

2. Thinning the Base Plate**: The desire to reduce the base plate thickness is well-known. Currently, 0.15mm tinplate is used for making lids in China, and some cold-rolled plate companies have announced the ability to produce 0.12mm cold-rolled plates for the lid industry. Therefore, thinning the base plate and enhancing hardness through secondary cold rolling is the development direction for the can (lid) industry.

Now that we understand tinplate, let's explore why merchants choose tinplate boxes for packaging various products.

 1. Light Protection

Light can trigger deterioration reactions in food and cause changes in proteins and amino acids. Vitamin C is particularly susceptible to degradation when exposed to light, leading to significant losses. Research indicates that milk in transparent glass bottles loses 14 times more vitamin C than milk in dark-colored bottles. Light can also cause oxidation odors in milk and the breakdown of nutrients like riboflavin and methionine. The non-translucent nature of tin cans maximizes the preservation of vitamin C.

 2. Excellent Sealing Properties

The barrier properties of packaging containers against air and other volatile gases are crucial for preserving nutritional components and sensory quality. Comparisons of various juice packaging containers have shown that the oxygen permeability rate directly affects the browning of juice and the preservation of vitamin C. Containers with low oxygen permeability, such as metal cans, glass bottles, and aluminum foil laminates, preserve vitamin C better, with metal cans being the best.

 3. Reductive Action of Tin

The tin on the inner wall of the tinplate can react with residual oxygen in the container during filling, reducing the chances of food components being oxidized. The reductive action of tin effectively preserves the flavor and color of light-colored fruits and juices, making tin cans a better choice for preserving nutrients and minimizing browning compared to other packaging materials. This extends the shelf life and improves the acceptability of the flavor quality.

 4. Health Benefits

Most tinplate boxes for food, except for a few light-colored fruit and juice cans, use internally coated cans to enhance the container's corrosion resistance. Due to the electrochemical action of metals, a small amount of iron dissolves into the canned food during storage, existing in the form of ferrous iron, which is easily absorbed by the human body, with a content of about 1 to 10 ppm. For fruit and vegetable products, the raw materials themselves do not contain much iron. With each 350 ml beverage can containing 5 ppm of iron, each can provides 1.75 mg of iron, which is about one-tenth of the daily intake of 18 mg. If the aforementioned fruit and vegetable juice beverage cans contain rich vitamin C, the iron is more easily absorbed. Therefore, tinplate packaged food and beverages are a good source of iron, and the nutritional significance of tinplate food is more profound.

These are the reasons why major merchants have abandoned traditional packaging in favor of tinplate boxes. The benefits of tinplate packaging, such as light protection, excellent sealing properties, the reductive action of tin, and health benefits, make it a preferred choice for a wide range of products.