Discussion on Physiological Characteristics and Design of Transport Package of Juicy Peach (I)

[Abstract] On the basis of elucidating the peculiar physiological phenomenon of peach fruit, the adverse effect of transport vibration on fruit was analyzed, and the design of shock-proof transport package suitable for peach was discussed.
Key words: Physiological characteristics; Peach; Vibratory; Transport packaging. CLC number: F762.3; TB485.3 Document code: B Article ID: 1001-3563 (2003) 04-0069-03

Physilolgical Characteristics of Juicy Peach & Discussion
On the Design of Transport Package of Fruit
ZHANG Rui-yu
(Chongqing Technology & Business Univ., Chongqing 400033, China)
Abstract: based on expounding the special physiological characteristics of juicy peach,the adverse effects of vibrations during transportation on the fruit have beem analyzed.The shockproof package design which is suitable for juicy peach to be transported has been discussed.
Key words: Physiological characteristics;Juicy peach;Vibration;Transport package

Peach is the best product in fresh peach, sweet and tender, juicy slag, nutritious and beautiful, constitutes a collection of advantages of eating quality, and thus deeply welcomed by the market. However, due to the above characteristics, the shelf life is only 2 to 3 days at room temperature, which is just like a “short-lived” phenomenon in the market.
The long-term storage and transportation of peaches is still a problem [1]. However, research on high-quality short-term storage and transportation of high-quality fruit, and the reduction of corruption during transportation are of great practical significance. Packaging is an extremely important technical link in storage and transport. The physiological characteristics of the peach fruit, the nature of the packaging, and the transport environment The various physical and mechanical factors pose a complex influence on the proper packaging design.

1 Physiological characteristics of peach fruit

After picking peaches, under the influence of the surrounding environment, a variety of complex and interrelated biochemical reactions are continuously carried out within the peach, and packaging, transportation, and other human actions will affect it, but the principle is only Moderate adjustment and control can not be excessive interference, damage.
Peach is filled with water, has a large intercellular space, and has a thin epidermis. Ethylene release peaks and respiratory peaks occur soon after harvest, and physiological aging symptoms such as tissue softening, flocculation, browning, and loss of flavor are lost, and various foods are lost. Injury and bacterial infections are also prone to occur, leading to fruit spoilage.
Peach is different from many types of fruit. It does not have a post-harvest ripening period. Its best quality is formed on the tree, so it is impossible to produce good quality as early fruits. During the high temperature of the harvest season, the time from reaching the best quality to decaying metamorphosis is very short, suggesting that it is difficult to store and transport it after sufficient maturity. In view of the quality and flavor of the peach, the appropriate harvest period of the peach should be when the best quality is basically formed.
Because of the metabolic activity, the peach is the key to post-harvest control quality. Generally it should be reduced to 2 to 4°C as quickly as possible, but at the same time, the peach is also sensitive to low temperature, and it is easy to feel the low temperature physiological disease at about -1°C.
In other respects, peach not only has obvious ethylene synthesis and release itself, but ethylene in turn will promote its aging and deterioration, thus reducing and eliminating ethylene effectively inhibits aging-related reactions; plant growth regulator GA can also inhibit ethylene Produced; 1% ~ 2% of calcium salts can inhibit the softening of peach [2], the use of these physiological responses can be used as an adjunct to improve the effect of peach packaging storage and transportation.
2 Peach transport packaging
2.1 Effect of transport on fruit The transport environment is more complex than the static storage environment. Due to the vibration of the vehicle's power machinery and the random vibration caused by the road surface, the peach fruit in the vehicle will be affected by vibration, friction and static load [3]. Vibration is a basic factor in the transport environment. The peach fruit is a complex anisotropic viscoelastic body. Its rigidity is very small, and therefore it absorbs vibrational energy. When the externally applied vibration is consistent with the natural frequency of the fruit, resonance phenomenon occurs and the fruit is affected. More vibration damage. If only considering the physical effect of vibration on the fruit, the impact of vibration mainly depends on the magnitude of the vibration acceleration, the number of vibrations and the frequency of vibration, but because the fruit is organic, the body and the vibration will also cause physiological effects. In practice, even if some Small vibrations that do not cause harm will also increase the absorption of fruits and vegetables due to repeated actions or long-distance transportation, resulting in softening of the flesh, reduced strength, etc. [4]. If the fruit has been subjected to mechanical operation, the breath rises immediately. phenomenon. Since the breath is a heat-producing process, the stimuli that would have been in normal breathing will cause the heat release to increase further, causing the temperature to increase and the damage to increase. In the peaches supply chain, transportation is a must, but the peaches that are easily damaged by themselves are often caused more serious damage due to friction, impact, vibration, etc. during transportation. The design of reasonable and effective packaging becomes a solution to this problem. The indispensable means of the topic [5].
2.2 Peach outer packaging - Corrugated cardboard boxes
2.2.1 The structure and size of the carton The quantity of containers: There is no absolute requirement for the quantity of fruit in general. In principle, manual handling should be convenient and should not be too heavy. Taking into account the characteristics of the peach fruit and the number of transfer in circulation more, in order to facilitate the wholesale, retail, with 7.5 ~ lOkg per box is better.
Carton volume: Peach fruit is large and has a certain difference in shape and volume. Therefore, it should be manually selected and graded before packing so that the size, shape and maturity of the fruit in the same package are as consistent as possible.
Considering the diameter of 70mm, it is estimated that each kilogram of fruit occupies a space of 0.0020-0.0025m3. If a better packing method is set for the peach fruit, and the buffer packing material is used, the items are counted and the carton volume can be obtained.
Carton size: Under certain materials, different carton sizes will have different pressure resistance. As a vulnerable fruit box, the compressive strength and stacking strength of the carton must be considered first, and at the same time, economical materials and beautiful appearance are required [6].
According to the packaging object and the actual conditions of storage and transportation environment, the design of the initial set of carton types, box type and cardboard structure composition, you can check the relevant data. Because within a certain range, when the box's pressure at the periphery of the mouth is constant, the height of the box has little effect on the compressive strength. Therefore, the use of the circulation environment requires that the carton has the compressive strength calculation formula, the Kjeldahl equation, and the integrated ring pressure of the corrugated cardboard. The value calculation formula is used to calculate, and on the premise of ensuring the safety of storage and transportation, combined with the rational use of materials, the specific dimensions of the carton can be obtained.
China has a variety of standardized carton boxes available for selection. At present, the use of cartons for fruit storage and transportation is very common. In practical applications, the optimum three-dimensional ratio of some commonly-used containers is more than the existing empirical data. Using it, combined with the specific packing volume, the initial size of the cartons can also be determined. .
(To be continued)