Analysis of primary, secondary and tertiary aromas in Vitis vinifera L. Syrah wines with an extemporaneous production cycle in two regions of São Paulo – Brazil, using GC-MS

Abstract

Context and purpose of the study – The aromatic perception is one of the main factors that influence the consumer when determining the wine’s quality and acceptance. Numerous factors (soil, climate, winemaking style, cultivar) can influence the volatile compounds. Some of these compounds are released directly from the grape berries while others are formed during the fermentation and aging processes. However, little is known about the quality and aromatic formation of Syrah variety in the winter cycle cultivated in São Paulo. This study aimed to characterize the primary (originated from the grape), secondary (fermentation) and tertiary aromas (evolution) of these wines, showing the wine potential from new producing regions in São Paulo state.

Material and methods – The microvinifications were made using the traditional method. The Syrah variety (clone 174 ENTAV – INRA ® on rootstock 1103P – clone 768 ENTAV – INRA ®) was conducted in double cordon VSP system, with winter harvest in Indaiatuba (low altitude and hot climate) and São Bento do Sapucaí (high altitude and cold) – Brazil. The analyses of volatile compounds were carried out in the main stages of the vinification process (must extraction, after alcoholic fermentation, after malolatic fermentation, before packaging and after 6 months in bottle). The samples were collected and frozen at -80 ° C until analysis. An Agilent 7890 GC system coupled to 5977 MS detector equipped with a Supelcowax column (30m x 0.25mm x 0.25μm film thickness) was used.

Results – Vines from the Indaiatuba region presented an average production of 7 bunches per plant. The bunches showed average weight of 76.5 g and size of 10.9 cm. Berries had 11 mm diameter and weighed 1.5 g. Must presented total soluble solids of 20ºBrix, total acidity of 105 meq.L-1, pH 3 and 1084 density. 24 primary aromas were found, such as lavender and apricot, 42 secondary aromas such as cooked apple and roses, and 17 tertiary aromas such as butter and honey. The vines of São Bento do Sapucaí presented an average of 9 bunches per plant. Bunches with an average weight of 101.8 g and length of 13 cm. Berries had a diameter of 12.5 mm and a weight of 1.5 g. Must presented total soluble solids of 21.5ºBrix, total acidity of 100 meq.L-1, pH 3 and 1090 density. The must had 29 primary aromas, such as mint and pear, 36 secondary aromas, such as honey and rose-orange, and 20 tertiary aromas such as wintergreen and mint.