Application of near infrared (NIR) spectroscopy for rapid quality assessment of grape mashes

1. Auflage 2015
ISBN: 978-3-8440-3589-6
Verlag: Shaker

Buch, Englisch, Band 2015,40, 168 Seiten, PB, Format (B × H): 148 mm x 210 mm, Gewicht: 252 g

Reihe: Schriftenreihe des Lehrstuhls Lebensmittel pflanzlicher Herkunft

The parameters commonly examined upon receival of grapes at wineries are insufficient for comprehensive quality assessment. Grape quality is mainly determined by the ripeness and phytosanitary status of the grapes and is indicated by changes in chemical composition. Ergosterol, being essentially contained and specific for the vast majority of fungi, including grape-rotting moulds and yeasts, was established as an objective and reliable marker for grape rot. However, conventionally required laboratory wet chemical analyses for comprehensive grape quality assessment are tedious, time-consuming, and costly. In contrast, near infrared/visible (NIR/VIS) spectroscopy represents a rapid alternative. An industrial spectrometer, especially designed for on-line process implementation, was applied in laboratory configuration to evaluate the feasibility of the prediction of ergosterol and 12 further quality-associated parameters in grape mashes. Ultimately, we have evaluated the feasibility of an on-line assessment for real-time analysis of grape mashes by NIR/VIS spectroscopy at production scale upon their receival at two wineries during three vintages. Models suitable for semi-quantitative prediction of 10 parameters were established as being valuable for multifactorial, holistic assessment of the composition of grape deliveries. Specialisation of the calibration models showed the potential for further improvement of the predictions. On-line NIR/VIS spectroscopy is promising for rapid and objective assessment of grape quality upon receival at wineries, which may enable improved systems for payment and quality management. Further acceptance criteria may be developed and food safety may be improved by detecting and rejecting spoiled grapes potentially containing mycotoxins.

Autoren/Hrsg.

Porep, Jan Ulrich