A physicochemical study on the effects of oak maturation of Ġellewża and Girgentina wines

Abstract

Amongst the Maltese indigenous grape cultivars (Vitis vinifera) Ġellewża and the Girgentina cultivars are the best known which is mainly due to the production of their wines with IĠT appellations. At the time of the study, the wines produced for these cultivars were red wines and sparkling Rose’s from Ġellewża and white non-sparkling and sparkling wines from Girgentina. A few Chardonnay-Girgentina blends were also available. Through a physicochemical study of a range of wines produced by local vintners of cultivars, several characteristics emerged about these wines including the high polyphenolic content (established through Folin-Ciocalteu Colorimetric Method), especially in Girgentina relative to other white wines of the world. Spectroscopic analysis revealed anthocyanin content to be very high for a white variety which sheds interest with regards to bioactive compounds content within such wines. Within this study, an innovative method of oak maturation was employed. It entailed using high toast French oak chips (Quercus alba) where finished wines were exposed to the wood in a non-oxidative environment. Through continued physicochemical analysis and sensorial analysis, it was concluded that there was indication of compatibility of oak maturation with these local wines with Ġellewża wines benefitting majorly, being red wines. Moreover, it was established that such a method could benefit wines requiring corrections. The method of oaking used was not stipulated as an alternative to traditional oaking methods but rather a costeffective method that can be used to enhances some wines. This degree was carried out following the award of a Tertiary Education Scholarships Scheme Scholarship.