Tea packaging technology and method analysis

As one of the three largest non-alcoholic beverages in the world, tea is hailed as a drink of the 21st century and is favored by the world for its natural, nutritional, and health quality. As a special product, incomplete packaging often damages the shape, color, fragrance, and taste of tea. To achieve long-term storage and transportation, tea must be effectively packaged.

1. Tea packaging technical requirements
Tea contains a variety of ingredients, such as light acid, tea Ning, tea, aromatic oil, protein, acid, lipid, vitamins, pigments, pectin, enzymes and minerals. These components are vulnerable to deterioration due to moisture, oxygen, temperature, light, and environmental odor. Therefore, when packaging tea leaves, the effects of the above factors should be weakened or prevented. The specific requirements are as follows.

1.1 moisture
Moisture in tea leaves is the medium of Tea biochemical changes. Low moisture content is conducive to the preservation of tea quality. The water content in tea leaves should not exceed 5%. For long-term preservation, 3% is the best. Otherwise, the acid in tea is easy to decompose, and the color, fragrance and taste of tea will change, especially at a high temperature, the deterioration speed will be accelerated. Therefore, in the packaging, you can choose to use moisture-proof performance, such as aluminum foil or aluminum foil steaming plating film as the basic material of the composite film for packaging materials for moisture-proof packaging.

1.2 anti-oxidation
Excessive oxygen content in the packaging may lead to the oxidation deterioration of some components in tea. For example, it is easy to oxidized to deoxidized vitamin C, and further the pigment reaction occurs in combination with amino acids to make the tea taste worse. Therefore, the oxygen content in tea packaging must be effectively controlled below 1%. In terms of packaging technology, inflatable packaging or vacuum packaging can be used to reduce the presence of oxygen. The vacuum packaging technology is to put the tea into a soft film packaging bag with good air tightness, and eliminate the air in the bag during packaging, resulting in a certain degree of vacuum, and then seal the packaging method; inflatable packaging technology is to discharge air while filling in nitrogen and other inert gases, the purpose is to protect the color, fragrance, taste of Tea remains unchanged, to maintain its original quality.

1.3 anti-high temperature
Temperature is an important factor affecting tea quality changes. The temperature difference is 10 ℃, and the chemical reaction rate is 3 ~ 5 times. At high temperatures, tea may aggravate the oxidation of containing substances, resulting in rapid reduction of effective substances such as polyphenol and accelerated deterioration of quality. According to the implementation, tea storage temperature below 5 ℃ is the best effect. 10 ~ At 15 ℃, the color of the tea is slow, and the color effect remains good. When the temperature exceeds 25 ℃, the color of the tea changes rapidly. Therefore, tea leaves are suitable for preservation at low temperatures.

1.4 Shading
Light can promote the oxidation of chlorophyll, lipid and other substances in tea, increase the odor substances such as pentaldehyde and Propylene Aldehyde in tea, and accelerate the aging of tea. Therefore, when packaging tea, shading is required to prevent the photocatalytic reaction of other components such as chlorophyll and lipid. In addition, ultraviolet rays are also an important cause of Tea deterioration. Shading packaging technology can be used to solve such problems.

1.5 gas Blocking
The fragrance of tea leaves is easy to lose and susceptible to external odor. In particular, the residual solvents in the composite films, the electronic ironing processing, and Hot Sealing processing will affect the flavor of tea, this affects the fragrance of tea leaves. Therefore, when packaging tea leaves, you must avoid escaping the flavor from the packaging and absorbing the odor from the outside. Tea packaging materials must have certain gas blocking properties.

2. Tea packaging method
As a special product, due to its own restrictions and objective conditions, tea packaging is different from packaging of other general products. Currently, the following methods are commonly used for tea packaging.

2.1 Metal Tank Packaging
The metal can is ideal for tea packaging because it has excellent anti-damage, moisture-proof and sealing performance. Metal cans are generally made of tin-plated sheet steel, and can be shaped in a square or cylindrical shape. Their covers are single-layer and double-layer. From the seal up, there are two kinds of General tank and sealing tank. In terms of packaging technology processing, generally the tank can adopt the packaging method of sealing the deoxidizing agent to remove the oxygen in the packaging. The sealing tank is mostly filled with inflation and vacuum packaging. Metal cans provide better protection against tea than composite films, and have a beautiful appearance and high elegance. The disadvantage is that the packaging cost is high, and the weight ratio of packaging to goods increases the transportation cost. The exquisite metal tank is suitable for the packaging of high-grade tea.

2.2 cartons
The carton is made of white paper, gray paper, etc. After printing, the packaging of the carton prevents breakage and the shading performance is also very good. In order to solve the problem that the tea aroma is volatile and not affected by the external odor, the tea is packed in polyethylene plastic bags and then loaded into the tray. The disadvantage of carton packaging is that it is easy to suffer from moisture. In the past few years, paper-plastic composite packing boxes have been used to overcome the problem of Box moisture, this kind of packaging material is made of the packing box using the inner layer of the plastic film layer or the card coated with moisture-proof Coating. It not only has the function of packaging the composite film bag, but also has the protective and rigid properties of the packing box. If a plastic bag is used as a small packaging bag, the protection effect is better.

2.3 plastic molding container Packaging
Plastic containers such as polyethylene, polypropylene, and polyvinyl chloride have the characteristics of being generous, beautiful, and good packaging and display effect, but their sealing performance is poor. They are often used as outer packaging in tea packaging, the packages are encapsulated in composite film plastic bags.

2.4 Composite Film Bag Packaging
Plastic composite film has many advantages, such as light weight, non-damage, good thermal sealing, and suitable price, and is widely used in packaging. There are many kinds of composite films used for tea packaging, such as moisture-proof glass paper/Polyethylene/paper/aluminum foil/polyethylene, double-axis tensile Polypropylene/aluminum foil/polyethylene, polyethylene/polypropylene/polyethylene, etc, the composite film has excellent air resistance, moisture resistance, fragrance protection, and odor prevention. Most plastic films have 80% ~ 90% light transmittance. To reduce the transmittance, ultraviolet suppression can be added to the packaging material or the light transmittance can be reduced by printing and coloring. In addition, the composite material can be used as the basic material of aluminum foil or vacuum aluminum plating film.