 IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Chemical diversity of 'special' wine styles: fortified wines, passito style, botrytized and ice wines, orange wines, sparkling wines 9 Experimental vinification of withered grapes of Vitis vinifera “Muscat of Alexandria”

Experimental vinification of withered grapes of Vitis vinifera “Muscat of Alexandria”

Abstract

AIM – The objective of the present work is to investigate wine produced from dehydrated grapes and vinified according to classical Roman manuals.

METHODS: Locally produced Muscat of Alexandria’s grapes were used for the sweet wine production, grown in the experimental vineyard of Instituto Superior de Agronomia (Lisbon, Portugal). The grapes were harvested manually slightly over-ripe and subjected to greenhouse drying. After 7-10 days dried grapes were transported to an experimental winery for various operations (e.g., grape weighing, sorting, crushing/destemming). Several maceration protocols were used comprising the addition of saltwater and white wine to whole bunches or destemmed grapes. Fermentation was conducted with the addition of commercial yeast. The standard physico-chemical parameters of wines were determined according to the OIV standards.

RESULTS: The results showed that all the samples had higher alcoholic content and residual sugar, ranging between 14.7 and 17 (% v/v), and 0.8 g/l to 18 g/l, respectively. Volatile acidity was less than 1 g/l in all wines, except in that obtained from withered grapes alone, probably due to stuck fermentations. In some of the wines, after fermentation, mousiness was clearly perceived.

CONCLUSIONS:

The obtained wines showed that it is possible to obtain acceptable products closely following the relevant protocols described in classical Roman manuals. The main problem was the detection of the mousy off-flavour that can be associated with the absence of sulphur dioxide addition to the musts before fermentation.

DOI:

Publication date: September 16, 2021

Issue: Macrowine 2021

Type: Article

Authors

Manuel Malfeito-Ferreira

Linking Landscape Environment Agriculture and Food (LEAF) Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal, Mkrtich Harutyunyan – Linking Landscape Environment Agriculture and Food (LEAF) Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal, Joana Granja-Soares – Enology Laboratory (DCEB), Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal

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Keywords

sweet wines; dehydrated grapes; historical wines; muscat of alexandria

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