The freshness and moisture resistance of food are crucial factors in packaging design, especially in the use of food paper packaging boxes. With the improvement of consumers' requirements for food quality, the function of packaging is not limited to protecting the appearance of food, but also needs to effectively extend the shelf life of food to ensure that its quality is not affected during transportation, storage and sales. How to ensure the freshness and moisture resistance of food paper packaging boxes has become an important direction of research and innovation in the packaging industry.
1. Multi-layer structure design
Many food paper packaging boxes adopt a multi-layer design, which includes an outer layer of paper material and an inner layer of waterproof and moisture-proof film or aluminum foil. The outer layer of paper provides good strength and durability, while the inner layer of moisture-proof film effectively prevents external moisture from entering the packaging box and reduces the contact between food and air. Especially in a humid environment, the inner film can effectively prevent moisture penetration and keep the food dry and fresh.
For example, for baked goods, packaging boxes often use a layer of food-grade PE (polyethylene) film or aluminum foil lining. These materials have excellent water-proof and air-tight properties, which can effectively prevent moisture and air from damaging food.
2. Airtightness
The freshness of food is not only related to the packaging material itself, but the airtightness of the packaging box is also a key factor. Food paper packaging boxes with airtight design can effectively isolate air and bacteria, reducing the risk of food oxidation and deterioration due to exposure to air. Many packaging boxes are equipped with press-fit sealing or self-adhesive sealing systems to ensure that there is no leakage space inside the packaging, thereby effectively extending the freshness of the food.
For example, fast food or ready-to-eat meal boxes often use paper packaging boxes with sealing functions to maintain the temperature and humidity of the food and prevent moisture in the air from affecting the taste and quality of the food.
3. Use of moisture-proof materials
Moisture-proofness is an important function of food paper packaging boxes, especially for foods that are easily affected by moisture and deterioration, such as bread, pastries, etc. In the design of packaging boxes, the moisture-proof layer is a key part. In addition to common plastic films, some innovative environmentally friendly materials are also used in moisture-proof packaging. For example, biodegradable moisture-proof coatings (such as plant fiber coatings) are gradually becoming a sustainable solution that can provide moisture-proof effects and meet environmental requirements.
Some paper packaging boxes use special coating technologies (such as water-based coatings) to form a waterproof barrier on the paper surface to prevent moisture from penetrating into the food through the paper, keep the food dry, and prevent the humid environment from causing the food to mold or rot.
4. Air permeability control
Although moisture resistance is essential, for some specific types of food (such as fruits or fresh vegetables), the packaging box also needs to have a certain air permeability to help the food "breathe" and release moisture. Air permeability control is achieved by adding micropores to the packaging box or using special breathable film materials. This not only prevents excessive moisture from accumulating inside the package, but also maintains the freshness of the food and prevents mold growth.
For example, some paper packaging boxes for fresh fruits and vegetables can maintain the ventilation of food and reduce the negative impact of excessive moisture on food quality through microporous breathable design.
5. UV protection
Some foods, especially those containing easily oxidizable ingredients (such as nuts, tea, chocolate, etc.), are very sensitive to UV rays. UV rays not only accelerate the oxidation process of food, but also affect the nutritional content of food. To solve this problem, modern food paper packaging boxes often use UV blocking materials, or add a UV protection functional layer to the packaging box through special coating design.
For example, packaging boxes with aluminum foil lining can effectively block UV rays and prevent food from deteriorating under sunlight or strong light.
6. Appropriate packaging size and shape
Appropriate packaging size and shape can also improve the freshness and moisture resistance of packaging boxes. Oversized packaging boxes will cause gaps in the food packaging, increase the contact between air and food, and accelerate oxidation and moisture. On the other hand, too small packaging boxes may not be able to fully accommodate food, resulting in excessive external pressure and affecting the sealing effect of the packaging. Therefore, precise packaging design can effectively reduce unnecessary space and ensure the sealing and moisture resistance of food in the packaging box.
7. Environmental protection and sustainability
With the improvement of environmental awareness, more and more consumers tend to choose packaging products with environmentally friendly characteristics. By using biodegradable pulp materials, environmentally friendly coatings and recyclable plastic films, food paper packaging boxes ensure that food is kept fresh and moisture-proof while reducing the burden of packaging on the environment. Environmentally friendly design not only meets the needs of the modern market, but also helps brands create a green and sustainable image.
