Effect of storage under CO2 atmosphere on the volatile, amino acid and pigment constituents in red grape (Vitis vinifera L. var. Agiorgitiko)

Volatiles of whole red grapes (Vitis vinifera L. var. Agiorgitiko) were isolated by using head-space technique. The grape prior to analysis were exposed for a period of 10 days under carbon dioxide atmosphere. This technique is currently used by wine-makers before the grapes are crushed and is called 'carbonic maceration'. The chemical composition of total volatiles was compared to this of control sample obtained from the same variety of grapes and stored for the same time period under normal atmosphere conditions. The composition of the amino acids and anthocyans, before and after carbon dioxide treatment, was also investigated. Significant differences in the constituents between the two groups were observed regarding the composition of the amino acids and anthocyans, as well as the volatile constituents, where 114 compounds were identified in the carbon dioxide treated sample, compared to 60 of the control sample