The raw material for the production of fresh processed must have ad hoc characteristics specific for that purpose. Melon and watermelon cubes must have an intense colour, a high content of soluble solids, be crispy, mustn’t ooze juice, must last several days intact, etc., but, most importantly, must have a good flavour. A project of the Foundation for Agrarian Innovation of the Ministry of agriculture and the Pontifical Catholic University of Chile researched, for several years, various production and conservation factors that influence the potential quality of the cubes. The research defined the main parameters that the raw material for the production of high quality cubed melons or watermelons, which are detailed in the following table, must meet:
Cubed Melon Watermelon
| Parameter | Value or Characteristic | Value or Characteristic |
| Pulp's colour a* | Intense orange (a* ≥ 15) | Bright red (a*≥25) |
| Thickness: | Pulp: 2,0 – 3,0 cm | Shell: 1 a 2,0 cm |
| Soluble solids content | 12º - 15 º Brix | 10º - 12 º Brix |
| Pulp's firmness | ≥ 20 Newtons | ≥ 10 Newtons |
| Duration in cold | ≥ 21 days | ≥ 21 days |
| Damage by cooling at 0ºC | None to mild | None to mild |
| Industrial Performance | ≥ 50% in weight | ≥ 45% in weight |
| Cubes lifespan | ≥ 5 days | ≥ 3 days |
| Fruits and cubes Aroma/flavour | Good (5) to Excellent (7) | Good (5) to Excellent (7) |
The integration of the desirable attributes identified in the picture, plus certain characteristics for each fruit (e.g. a small seminal cavity in the melons and the absence of seeds in watermelons), forced researchers to produce and evaluate a wide range of varieties of both species to objectively select the most suitable ones for processing them into cubes. Numerous pre-and postharvest studies conducted have allowed researchers to identify different varieties of melon, such as Diva (Origene), Fiji (Harris Moran) and Magenta (Nunhems), as well as varieties of watermelons such as the Ashira (Origene), Hummingbird (Seminis) and maximum (Origene), which meet these requirements and are recommended for the production of cubes. Moreover, since the seed companies have recognized this market's importance, the genetic improvement of melons and watermelons will result in new varieties that will be more suitable for fresh processing.
It should be emphasized that the qualitative characteristics of the varieties depend on several factors such as the region where they are produced, the crop's season, cropping system, maturity index, etc.
The value and characteristics identified in order to reach the raw material's optimum quality are commonly obtained in the Summer season in semi-arid Mediterranean climate areas like the ones in many countries of the Mediterranean basin, eg. Spain, France, Greece and Italy, and specific regions of America, for example, the central region of Chile and the State of California in the United States. In the past, these countries were forced to import the raw material to produce consistently high quality products. Obviously, Chile, due to its climatic condition and off-season production in relation to the Northern Hemisphere, can produce materials that meet the identified requirements during the austral Summer months, from December to March, making it an obvious source of high quality fruits for processors in the Northern Hemisphere countries, such as Canada and the United States.
In conclusion, the research project has helped define the objective characteristics that the melon and watermelon, as raw material, must meet to be able to obtain high quality fresh processed products. It also identified several varieties that meet these characteristics, spread innovation in Chile, and generated the necessary knowledge for exporting high quality raw material to processors in North America.
More information:
Christian Krarup
Ing. Agr., M.Sc., Ph.D. Senior Lecturer
Faculty of Agriculture and Forestry Engineer
Pontificia Universidad Católica de Chile
T: 56-2-686-4126[email protected]
