Rapid and non-destructive method to assess in the vineyard grape berry anthocyanins under different seasonal and water conditions*

Abstract

Background and Aims: Monitoring of anthocyanins (Anth) in winegrape (Vitis vinifera L.) is fundamental for the production of top-quality red wines. This work was aimed at testing a new fluorescence-based sensor for Anth detection in the vineyard. Significance of the Study: The present study showed a new important innovative technology for viticulture. The sensor evaluation of the large spatial and temporal heterogeneity in Anth accumulation can be useful as support parameter in the harvest date decision or for vineyard zoning of phenolic maturity. Methods and Results: Anth in grape (cv. Aleatico) bunches attached to the vine were monitored non-destructively in the field using a fluorescence-based sensor during the 2008 and 2009 seasons and under different water regimes. The ANTHRG index = log(far-red-fluorescenceR/far-red-fluorescenceG), with fluorescence signals excited with red (R) and green (G) light, was inversely correlated through an exponential function (r 2 = 0.875) to the Anth concentration derived from the HPLC analysis of berry skin extracts. ANTHRG was effective in detecting the earlier ripening process in 2009 with respect to 2008 and differences in the Anth accumulation between seasons and in relation to different water regimes. Water deficit imposed in 2009 enhanced Anth concentration in berries because of a reduction in berry size but also an increase of Anth biosynthesis. This effect was observed by both destructive and ANTHRG non-destructive measurements. Conclusions: Our results show that the employed fluorescence sensor represents a reliable, rapid and non-invasive tool for monitoring and determining Anth accumulation in situ.

Non-destructive Assessment of Highbush Blueberry Fruit Maturity Parameters and Anthocyanins by Using a Visible/Near Infrared (vis/NIR) Spectroscopy Device: A Preliminary Approach

“…Vitis vinifera (Tuccio et al, 2011;Giovenzana et al, 2014), and Prunus avium (Nagpala et al, 2013). It is noteworthy that blueberry healthy or It is important to point out that, for both cultivars, the relationship between I AD data and SSC was even lower than those detected between I AD and ANTH concentration (Table 3).…”

“…In this way, some technologies operating on visible and near infrared (vis/NIR) spectroscopy can allow checking in real-time the ripening progress of fruits (Bonora et al, 2013), monitoring the physiological changes of a great number of fruits with a high precision. Interestingly, reflectance-spectroscopy-based techniques have been successfully used for the detection of anthocyanins in fruits including grape clusters (Tuccio et al, 2011).…”

Relationship between total solid content and red, green and blue colour intensity of strawberry (Fragaria x ananassa Duch.) fruits

“…The portable sensors of fruits ripening directly applied at field levels to predict the best harvesting period (Tuccio et al, 2010). Bray (2009) explained that many constituents of quality including that those contribute to taste, aroma and antioxidant potential can be quantified by measuring reflectance of the visible regions (400 -780 nm).…”

Vineyard Practice

“…Regrettably, depth of color does not necessarily directly correlate with ease of extraction (e.g., Rustioni et al, 2011), wine color, or its stability. Advances in near-infrared spectroscopy (NIRS) may assist by soon permitting rapid (real-time), inexpensive, and accurate winery assessment of sugar, acid, and color indicators (Cozzolino and Dambergs, 2010;Tuccio et al, 2011). Even features such as skin hardness can affect the fragility of cell walls and the ease with which important skin phenolics are released (Rolle et al, 2011b).…”