The table grape production has significantly increased in the last years – from 15.7 million tonnes in year 2014 to more than 27 million tonnes in 2018. In Slovenia, the production of table grapes is insignificant, although the environmental, technological and market conditions are suitable. The production of high-quality table grapes demands a lot of manual work and consistent an implementation of technical measures, such as leaf removal, shoot thinning, grape cluster thinning, fertilization, spraying, irrigation and setting plastic foil or nets for protection. Harvesting of table grape at certain grapevine cultivar requires several grape pickings. Parameters that must be considered are largely connected to visual and sensory profiles, as well as to the refractometer measurements of the total soluble solids – for the edible ripeness, grapes must have at least 16 °Brix. For packing, the grapes must first be cooled down to 4 °C and all inadequate berries have to be removed. Afterwards, they are packed in a paper or cardboard package, which is combined with a piece of sponge. After the harvest, table grape tends to rot very easily, therefore have to be stored at 0 °C and at the relative air humidity of 95 %. In the past, SO2 was used to control the development of the diseases on stored grapes. However, it has been gradually replaced by UV-treatment, since SO2 has negative impacts on the grape quality, human health and the condition of the equipment. At a 3.6 kJ/m2 dose at 4 °C, UV-treatment has no visible impact on the chemical properties of the grapes. SO2 can also be replaced by O3 – a prospective antimicrobial substance, used to prevent the decaying of the grapes, or by packing in a controlled environment, which prevents the stems from turning brown and preserves the visual and sensory profiles of the grapes.
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