Preservation of corrugated cartons
(1) Paper-based processing and preservation technology Paper-based processing and preservation technology refers to adding raw materials or additives with fresh-keeping functions to the original paper-making raw materials when manufacturing fresh-keeping packaging paper. After the packaging is produced, the fresh-keeping functional raw materials or additives that are added during the packaging of the agricultural crystals will exert their freshness. Paper-based processing and preservation technology The most common method is the use of Chinese herbal medicine as a papermaking additive. For example, herbal slag is used as an additive for fresh-keeping packaging paper.
The paper-based processing preservation technology is characterized by the preservation of the cardboard (sheet) before forming. Including raw material processing (denaturation or modification) in the original sense to add additives with functions such as preservation, preservation, sterilization, etc., it is also possible to add or change the original material composition. In a strict sense, the paper-based processing and preservation technology is a category of paper packaging materials and belongs to the development and manufacture of special packaging paper.
(2) Integral infiltration of fresh-keeping technology Integral infiltration of fresh-keeping technology involves the infiltration of liquid ingredients with different preservation effects in the packaging of the paperboard. After being packaged, the components penetrated in the package will exert different preservation effects when fresh produce is packaged.
The whole infiltration fresh-keeping technology mainly utilizes the water absorption of paper, and at the same time, the substances with fresh-keeping function are dissolved into the internal gaps in the paper. The key to this technology is to select different infiltration material components for different agricultural products. These substances include special materials such as hydrophobic, eucalyptus, and antioxidants.
(3) Paper surface treatment and fresh-keeping technology Paper surface treatment and fresh-keeping technology mainly refers to coating on the paper surface (or covering the technical block diagram of the fresh-keeping corrugated cardboard box of Fig. 2 and other materials) or surface spraying. The purpose is to increase the tightness of paper packaging and reduce the evaporation and loss of moisture or other easily evaporating substances (components) of fresh produce, so as to achieve the effect of freshness preservation. For example, leafy vegetables or spices are used in this way to extend shelf life.
figure 2
The spraying of the paper surface is mainly coated with colloidal or oily substances on the surface of the packaging, so that the paper packaging can increase the rigidity and strength, and at the same time, the water evaporation rate of the fresh agricultural products can also be reduced to achieve the purpose of preservation.
(4) Hole arrangement fresh-keeping technology Hole-arrangement fresh-keeping technology refers to the arrangement method of the ventilation holes in paper packaging. Including the size of the pores of the paper itself and the arrangement of the vents specially provided on the package.
Paper's own pores are difficult to change after cardboard is made, but in order to use existing papers to produce fresh-keeping packaging with a certain porosity (transmittance), it is necessary to rationally select papers of different densities or to combine papers with different porosity or Composite use. The vent holes on the packaging are used to produce holes with different sizes and orientations for the permeability of the agricultural products that require higher air permeability during packaging. For example, fruits and vegetables packed in corrugated boxes have special ventilation holes for long-distance transportation and storage. It is the easiest and most economical method to open the vent directly on the package, but it will affect the strength and life of the package.
(5) Additional structure preservation technology
This technology is to achieve the preservation by adding accessories in the carton. For example, in the interior of the packing box, there are corners, pads, partitions, etc. that have special functions (oxygen absorption, ethylene absorption, moisture retention, mildew proofing, etc.). These attachments or additional structures can be individually formed into a single functional accessory (carton accessory) or can be made into a multi-functional series of carton attachments. When used, choose according to different products and circulation, storage environment, shelf life.
2. Types of fresh-keeping corrugated cartons (1) Anti-bacterial fresh-keeping corrugated cardboard and cartons Fresh-keeping of fresh fruits and vegetables is important for the control of environmental conditions such as temperature, humidity, and air in packaging containers. For example, maintaining a moderately low temperature can inhibit the respiration of the contents. Maintaining proper humidity can reduce evaporation of water, and the ethylene gas emitted from the contents should be eliminated to suppress aging. In addition, another important reason that is harmful to the preservation of fruits and vegetables is the wilting and decay of fruits and vegetables caused by the contamination of pathogenic microorganisms. Therefore, how to take measures to curb the proliferation of microorganisms in order to achieve the purpose of anti-bacterial preservation is also a problem that cannot be ignored. The antibacterial and preservative corrugated cardboard is coated with a layer of antibacterial antiseptic on the surface of the liner of the paperboard, and the antiseptic has no effect on food hygiene. Its composition as shown