Development of a new procedure for the determination of the reactivity of brandies used in wine fortification

• Type: Article in International Scientific Journal
• Date: 2021

Authors

Azevedo, J (Author) Other; Pissarra, J (Author) FCUP; Amaro, F (Author) Other; Luis F Guido (Author) FCUP; Joana Oliveira (Author) FCUP; Lopes, P (Author) Other; de Pinho, PG (Author) Other; Nuno Mateus (Author) FCUP; Victor de Freitas (Author) FCUP

Journal

Title: OENO One

Vol. 55

Pages: 161-172

ISSN: 2494-1271

Publisher: Vigne et Vin Publications Internationales

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Other information

Authenticus ID: P-00V-B8T

DOI: 10.20870/oeno-one.2021.55.3.4676

Abstract (EN): The main purpose of this work was to describe and validate a new methodology for the determination of a brandy reactivity index (BRI) towards flavan-3-ol compounds in wines (catechins and condensed tannins) and to correlate this index with the amount and type of aldehydes present in those brandies. This new method consists of two main reactions: a) the ability of aldehydes to react with C8 and/or C6 positions in the phloroglucinol ring of a catechin present in excess (A ring); b) further reaction of the remaining free catechin with p-dimethylaminocinamaldehyde (DMACA) yielding to the formation of a blue compound that can be quantified by Visible spectroscopy at 640 nm. The impact of different experimental conditions such as reagent concentrations and reaction time on BRI were also evaluated. The method was validated through the determination of repeatability (intra-day variability) and reproducibility. The repeatability was considered acceptable with a CV of 11.87 %. The analysis of the reproducibility variance S2R (11.59), the reproducibility limit R (9.5) and the reproducibility coefficient of variation, CVR (15.25 %) postulates BRI methodology to be reliable and robust. Using the developed methodology, the BRI of fourteen different commercial brandies and some pure standards aldehydes were determined. The aldehydes present in brandies, and the content of total aldehydes were determined by GC-MS and then correlated with the BRI. In general, it was observed a direct correlation between the BRI and the concentration of total aldehydes, in particular acetaldehyde.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12