Presentation is important: packaging and packaging for export cherries

By Trio Kimün SPA: Francisca Barros, Militza Ivelic, Jessica Rodríguez

Before the start of each cherry season, we are faced with the decision of purchasing packaging materials for our fruit. Packaging plays a fundamental role when sending the fruit to the different destination markets and must meet basic requirements such as: protecting the product from damage, preserving it during the logistics process (stable to thermal changes and humidity), communicating and inspiring the consumer with an attractive design and presentation.

The fruit industry has made important technological developments and changes related to packaging automation and packaging innovation to comply with the legislation and regulations of the destination countries, ensure efficient operation and logistics in the different stages of the production chain such as harvesting, selection and classification, cooling and transportation, as well as maintaining and prolonging the shelf life of the product.

The first contact of the receiver of our cherries occurs at the moment of opening the container, so the shape, structure and presentation of the pallet are important aspects to consider (Figure 1). To achieve proper palletizing, special care must be taken in the following points:

-Characteristics of wooden pallet bases: dimensions according to the requirements of the destination market, dry wood certified according to NIMF No. 15 (standard that regulates wood packaging for the international market and describes phytosanitary measures to reduce the risk of introducing pests related to wood packaging (SAG)).

Pallets must be designed taking into account the box to be used, ensuring that it is well supported on the boards in order to achieve good stacking. In addition, the separation between the boards must allow adequate air circulation between the pallet and the vertical vents at the bottom of the box. We must remember that, although cooling in pre-cooling tunnels is done through horizontal or header vents, on the ship the air movement is vertical.

-Quality and posture of the corner pieces: Corner protectors are usually made of cardboard in the shape of a V with a 90-degree angle, which serve the function of unifying a load and also being a protective element for the vertices of the pallet, so their quality must be such that it provides the necessary resistance for this purpose. As for the appearance of the corner protector, white corner protectors have been used mostly, although there are also “kraft” corner protectors, colored ones (in combination with one of the colors of the box design, (Figure 2) and printed ones (highlighting the exporter's brand).

–Straps and strapping: The strap is the palletizing element that allows the different components (boxes/pallets/corners/racks) to be joined together, forming a large unit. The strapping material used is mainly white polypropylene (PP) or polyester (PET). They are also available in green or transparent (Figures 1, 2 and 3), in the latter case, allowing the graphic of the boxes not to be covered. Regarding strapping, the number of vertical and horizontal straps and their respective positions must be considered. In the destination market we have been able to observe the arrival of pallets with 7 to 14 rows of horizontal straps, affecting their final stability. 

A common mistake to observe regarding the position of the straps is that they cover the ventilation holes of the boxes. (Figure 6)

-Grills: To protect the top of the pallet and allow for firm vertical strapping, wooden or perforated plywood grids, perforated cardboard with corner pieces (Figure 4) or simply pieces of corner pieces are used. Make sure that the perforations coincide with the vents in the boxes to ensure vertical air flow.  

-Separators: To ensure pallet stability, especially in 2.5kg bottom and top boxes, which is a common format for the Asian market, some exporters use plywood or cardboard separators with holes that vary in number depending on the box (Figure 5). It is important to consider blocking vertical vents as much as possible.  

Pallet stability and presentation problems at destination are generally due to more than one factor. In relation to factors that have to do with the selection of materials and pallet assembly, we can mention: weak corner pieces, lack of strapping, problems with box strength, the “Easter tree” problem (side of the lid longer than the bottom (figures 8, 9 and 10)), poor stacking of boxes as the pallet increases in height, inadequate stacking at the base of the pallet (Figure 6), position of box handles facing outwards (in 2.5kg packages), box strength failures (Figure 7). Based on aesthetic problems in the pallets, we can mention the disordered position of labels on the boxes, a mixture of boxes with different graphics on the same pallet (Figure 3). Another element to consider is that our receivers also do not like the mixture of calibers within the same pallet because this makes it difficult to sell.

Regarding the boxes used for cherries in the Asian market, there are different formats, designs and materials. Corrugated cardboard boxes have been used mainly for the Chinese market (in some cases micro-corrugated board is used for the lids), there are also some versions in plastic and solid chipboard. In the case of corrugated cardboard boxes, these can be self-assembling or machine-assembled. The resistance to stacking and the ventilation of the box (ventilated area) are factors to be analyzed when choosing the box die to be used, considering that we must cool and store the fruit at low temperatures and high relative humidity. On the other hand, we must not forget the ease and speed of assembly (manual and/or automatic system) considering the labor problems we have faced in recent seasons.

The most commonly used format is the 30x50cm 5kg box (bottom and lid), followed by the 2.5 and 2kg formats (bottom and lid) or suitcases where the packaging has a handle to hold it. There are also MASTER boxes of 400x300cm, where 2 boxes of 2.5kg are placed, as well as 600x400cm boxes, which contain 2 or more suitcases (depending on the format and height of the head) and are normally flexographically printed (similar to a printing stamp), to reduce their cost.

For this particular market, graphics and print quality are important factors to consider, considering that giving cherries for the Chinese New Year is a highly appreciated gift, and where small boxes (2-2.5kg) have become a symbol of luxury (Figure 11). High-quality graphics printing is achieved either through preprint or offset printing techniques.

Regarding the themes of the box graphics, the most common ones are animals (many of those included in the Chinese horoscope), cherries (fruits, flowers and trees) and motifs related to Chile (mountain ranges, araucarias, “moais”, native animals, etc.) or a combination of these themes. 

When selecting the colors to be used, it must be taken into account that these symbolize different values for Chinese culture. Thus, yellow/gold colors symbolize wealth and social position, while red represents happiness, joy, good luck. These two colors are the most used in the designs of our boxes.                                                                                

To further highlight the graphics on the boxes, the different printing technology providers have incorporated graphic solutions or finishes such as Deep Off, UV varnish, foil and metallic cardboard that make a difference by providing different textures and sensations (Figure 12). On this last point, it is worth noting that all these finishes increase the price of the packaging, so it is important to first value the benefit and verify that the gift packaging (2-2.5 kg box or suitcase) is better paid for per kilogram of packed fruit. As this is a high-end packaging, obviously the fruit that should be inside must be of premium quality.

Another important material to highlight is the modified atmosphere bag, which must be heat sealed in order to achieve the concentration of gases for which it was designed and to allow the fruit's shelf life to be extended, reduce weight loss and the risk of rot developing.  

Inside the bag, which is usually gusseted, a moisture-absorbing paper is placed and the fruit is placed on top of it. The objective of this material is to absorb the humidity of the bag, especially in the packaging where the fruit carries water from the processing line.

To automate the packaging of fruit, innovation has been achieved through the development of laminated film that is sealed to trays or “punnets” (from 500g to 2lb) generating a modified atmosphere. There is also the possibility of the Flow Pack system in which the tray is individually wrapped by the film designed with the required permeability to generate the atmosphere.

Packaging and the materials they are made of are interrelated, so their correct design and selection, based on technical and economic criteria, is of fundamental importance to ensure that the product reaches its destination in the correct conditions for marketing.