New Zealand Pinot Noir, Extending Maceration Time

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dc.contributor.advisor Kilmartin, P en Carter, Danielle en 2018-07-31T23:35:08Z en 2018 en
dc.identifier.uri en
dc.description Full text is available to authenticated members of The University of Auckland only. en
dc.description.abstract Pinot Noir is increasingly important to the New Zealand wine industry and has grown to become the second largest wine in production and export after Sauvignon blanc. This thesis investigates the chemical composition of commercial Pinot Noir wines made from three different vineyards, using a five-month extended maceration practice. The first objective was to see if there were any trends relating to phenolics and extended maceration. The second objective was to see if there was a relationship between extended maceration and colour development and colour stability. The final objective was to use an acid catalysed phloroglucinolysis HPLC method to gather deeper information about oligomeric phenolic fractions. The spectrophotometer results show that both normal treatment and extended maceration wines decrease in red pigments and wine hue readings over the five months after fermentation. At the five-month point, the normal treatment wines had higher overall levels of yellow pigments, colour density, total phenolics, red pigments in absence of bleaching and total red pigments. Extended maceration wines showed larger spectrophotometric values for monomeric anthocyanins and SO2 resistant pigments. When comparing the phenolic HPLC results, the extended maceration wines had higher concentrations of gallic acid and epicatechin, and slightly lower concentrations of catechin than the normal treatment wines. The caftaric acid, p-coumaric acid and coutaric acid concentrations were highest in the normal treatment wines, with the associated caffeic acid and grape reaction product concentrations higher in the extended maceration wines. When comparing the results from the acid-catalysed phloroglucinolysis HPLC method, overall the extended maceration wines had either the same or higher concentrations of associated flavan-3-ols by five-month point. The exception was the largest phloroglucinol adduct peak, the epicatechin phloroglucinol adduct, which was higher in concentration in the normal treatment wines. Overall, the quicker normal treatment method showed good phenolic and spectrophotometric results when compared to the extended maceration wines. The research shows the need for more tests on such after bottling to see if colour and phenolic parameters change significantly with wine aging. en
dc.publisher ResearchSpace@Auckland en
dc.relation.ispartof Masters Thesis - University of Auckland en
dc.relation.isreferencedby UoA99265071911602091 en
dc.rights Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. en
dc.rights Restricted Item. Available to authenticated members of The University of Auckland. en
dc.rights.uri en
dc.title New Zealand Pinot Noir, Extending Maceration Time en
dc.type Thesis en Chemical Science en The University of Auckland en Masters en
dc.rights.holder Copyright: The author en
pubs.elements-id 750616 en
pubs.record-created-at-source-date 2018-08-01 en

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