Identification of the major drivers of 'phenolic' taste in ... - GWRDC

More documents

Recommendations

Info

AWRI: Identification Of The Major Drivers Of ‘Phenolic’ Taste In White Wines 68 Figure 8-2. Flow chart of different pressing treatments to obtain white wine of different phenolic levels (2011 Vintage)
AWRI: Identification Of The Major Drivers Of ‘Phenolic’ Taste In White Wines 8.3 Analytical Methods 8.3.1 UV Spectra and Somers Measures (2010 and 2011 wines) Analyses of the finished wines were carried out following bottling. The UV spectra were recorded in 2 mm matched quartz cuvettes using a Varian Cary 300 UV-Vis spectrometer. Total phenolics, total hydroxycinnamates and flavonoid extractibles were calculated as per Somers and Ziemelis (1985) (Appendix A.1). 8.3.2 Phenolic Composition by HPLC (2010 wines only) A detailed analysis of the phenolic composition of the 2010 wines was determined using HPLC-DAD analysis following evaporation of the alcohol and a four-fold concentration under reduced vacuum (Section A.3). Peak identification was carried out by comparison of UV spectra derived from a sample that had been analysed by HPLC-MS/MS. Peak area was extracted from the chromatograms and expressed in equivalent mg/L of a related parent phenolic compound. All hydroxyphenolics/benzoic acids/flavanol were expressed in gallic acid equivalents (GAE), all hydroxycinnamates and grape reaction products (GRP) derivates as ferulic acid equivalents (FAE) and flavonols as quercetin-3-glucoside equivalents (Q3GE). 8.4 Sensory Methods 8.4.1 Wines from 2010 vintage Tasters Thirteen tasters (five males and eight females) were trained for this study. All were experienced in the descriptive analysis of aroma and flavour, and the palate sensations of bitterness, astringency and acidity. Ten of the tasters had previously been involved in taste and texture profiling of phenolic fractions taken from commercial white wines. Taster Training Training was conducted over six sessions. The first three sessions involved attribute generation, attribute definition and refinement, with the latter also involving identifying attribute redundancies. During these sessions, two wines made from whole bunch pressed and free run juices (low phenolics) were tasted and compared with two wines made from either hard pressing juices or those that had undergone extensive skin contact before fermentation (high phenolics). Standards for astringency, viscosity and bitterness (Appendix B, Table B-4) were also presented. A commercial white wine made with extensive pre- and 69
Page 1 and 2:
Identification of the major drivers
Page 3 and 4:
AWRI: Identification Of The Major D
Page 5 and 6:
Page 7 and 8:
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18: AWRI: Identification Of The Major D
Page 67: AWRI: Identification Of The Major D
Page 113 and 114: RT (min) AWRI: Identification Of Th
Page 115 and 116: RT (min) AWRI: Identification Of Th
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139:
show all

Identification of the major drivers of 'phenolic' taste in ... - GWRDC

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?