Characterization of Key Odorants in Chardonnay Seeds

Abstract

Chardonnay marc, a co-product of the winemaking industry, is a combination of skins, seeds, and stems remaining after the juice is pressed from the grapes. This co-product amounts to over half a million tons per year. Recently, Chardonnay marc has been emerging as a healthy and flavorful food ingredient. The aroma contribution of the seeds to the overall aroma of Chardonnay marc remains unknown. In the present study, 43 odorants were identified in Chardonnay seeds employing aroma extract dilution analysis (AEDA) performed on a distillate prepared by solvent extraction and solvent-assisted flavor evaporation (SAFE) distillation. Of those, 6 odorants with a flavor dilution (FD) factor ≥64 were quantitated using stable isotope dilution assays (SIDAs). The odorants included (2E,4E)-deca-2,4-dienal (fatty, OAV 8028), 3-methylnonane-2,4-dione (hay, OAV 4772), (2E,4E)-nona-2,4-dienal (fatty, OAV 1750), hexanal (green, OAV 1481), linalool (floral, citrus, OAV 28), and 2-phenylethanol (floral, rose, OAV 2). An aroma simulation model was prepared based on the quantitative data, and its aroma was a close match to the Chardonnay seed powder. Omission studies applied to the aroma simulation model showed that hexanal and 3-methylnonane-2,4-dione were the key odorants driving the aroma profile. This research established a foundation for future studies aimed at optimizing the flavor of Chardonnay marc powder.

Contribution of Key Odorants from Skins, Seeds, and Stems to the Aroma of Chardonnay Marc: A Valuable Coproduct of the Wine Industry

“…The omission experiments on Chardonay marc seeds were previously described in the work of Warner and Munafo (2022) and will be mentioned here in pursuance of comparison. Briefly, the hay-like smelling 3-methylnonane-2,4-dione and the green/fatty smelling hexanal were determined as the key odorants in the marc seeds because of the significant difference between their omission models and the full marc seed aroma model ( p ≤ 0.01) …”

“… a OAVs of the main odorants in Chardonnay marc skins, seeds, and stems when being evaluated separately. b Proportionally calculated OAVs of the main odorants in Chardonnay marc skins, seeds, and stems based on their mass balance in the whole Chardonnay marc (skins, 60%; seed, 35%, stems, 5%). c Key odorant identified in Chardonnay marc skins, seeds, and stems, as determined by omission studies. d Key odorant identified in Chardonnay marc skins only, as determined by omission studies. …”

“…Previous studies have characterized the odorants of the skin and seed components of Chardonnay marc to determine their contributions to the overall marc aroma. , In the skins, 12 odorants were found with an odor activity value (OAV) > 1, indicating they are potentially important contributors to the skins’ aroma. These included 3-methylnonane-2,4-dione (hay), β-ionone (floral, violet), (2 E ,4 E )-nona-2,4-dienal (fatty), β-damascenone (cooked apple), hexanal (green, fatty), oct-1-en-3-one (mushroom), linalool (floral, citrus), (2 E ,4 E )-deca-2,4-dienal (fatty), 2-phenylethanol (floral, rose), 3-(methylsulfanyl)­propanal (potato), 4-hydroxy-2,5-dimethyl-3­(2 H )-furanone (HDMF) (caramel), and ethyl octanoate (fruity) .…”

“…These included 3-methylnonane-2,4-dione (hay), β-ionone (floral, violet), (2 E ,4 E )-nona-2,4-dienal (fatty), β-damascenone (cooked apple), hexanal (green, fatty), oct-1-en-3-one (mushroom), linalool (floral, citrus), (2 E ,4 E )-deca-2,4-dienal (fatty), 2-phenylethanol (floral, rose), 3-(methylsulfanyl)­propanal (potato), 4-hydroxy-2,5-dimethyl-3­(2 H )-furanone (HDMF) (caramel), and ethyl octanoate (fruity) . In the seeds, six odorants were found with an OAV > 1, which included (2 E ,4 E )-deca-2,4-dienal (fatty), 3-methylnonane-2,4-dione (hay), (2 E ,4 E )-nona-2,4-dienal (fatty), hexanal (green, fatty), linalool (floral, citrus), and 2-phenylethanol (floral, rose), with hexanal and 3-methylnonane-2,4-dione being determined as key odorants in the seeds . To the best of our knowledge, no previous work has yet determined the key odorants in the skins or stems nor fully determined the contribution of each marc component to the overall aroma of the whole marc.…”

“…12 In the seeds, six odorants were found with an OAV > 1, which included (2E,4E)-deca-2,4-dienal (fatty), 3methylnonane-2,4-dione (hay), (2E,4E)-nona-2,4-dienal (fatty), hexanal (green, fatty), linalool (floral, citrus), and 2phenylethanol (floral, rose), with hexanal and 3-methylnonane-2,4-dione being determined as key odorants in the seeds. 13 the best of our knowledge, no previous work has yet determined the key odorants in the skins or stems nor fully determined the contribution of each marc component to the overall aroma of the whole marc.…”