A team of researchers from the Biotechnology and Post-harvest quality group of the Institute of Science and Technology of Food and Nutrition (ICTAN-CSIC) of Madrid has provided viable solutions to maintain the physiological and nutritional quality of table grapes in their post-harvest period through the application of non-polluting treatments. The method even allowed the fruits to maintain all their organoleptic properties a month after being harvested.
The study confirmed that the application of two non-polluting gaseous treatments with 20% CO₂, carried out for 3 days at the beginning and in the middle of the conservation of table grapes at 0 ° C, maintains the quality of the table grape clusters, specifically of the Autumn Royal variety.
Researchers also observed that at the end of the conservation, before the table grape clusters reach consumers, they present higher levels of flavonoids, such as anthocyanins and flavonols, which are compounds that have beneficial health properties.
The scientists observed that applying the gaseous treatment once or twice was effective, but determined that carrying out the second treatment improved the quality of the clusters. The research also revealed that the accumulation of the different flavonoids analyzed was regulated by the expression of key genes.
The research has also shown that the use of an analytical methodology, based on voltammetric techniques, makes it possible to easily evaluate the influence of the treatments applied on the composition of antioxidant compounds in the samples.
The study is entitled "Regulation of the flavonoid biosynthesis pathway by means of a single or double short-term CO₂ treatment in black table grapes stored at low temperature", and it has been published in the Plant Physiology and Biochemistry journal. It was carried out by doctor Irene Dominguez, from the University of Almería, and scientists Irene Romero, Noemi Morales, Maria Isabel Escribano, Carmen Merodio, and Maria Teresa Sanchez-Ballesta, all of which belong to the ICTAN-CSIC's Department of Characterization, Quality, and Safety.