Unravelling the nitrogen profile of the new descendant varieties of Monastrell. Preliminary study

Abstract

The amino acid composition of grape must is a critical factor influencing both fermentation dynamics and the sensory attributes of wine. Amino acids act as essential nitrogen sources for yeast metabolism, directly affecting fermentation performance and the production of secondary metabolites. Beyond their nutritional role, amino acids serve as precursors for a wide range of volatile compounds, including higher alcohols, esters, and aldehydes, which are key contributors to wine aroma.

This is a preliminary study on the amino acid content of the new red grape varieties descendants of Monastrell (Calnegre, Carmolí, Gebas, MS104, Myrtia and Quípar) developed at IMIDA and its parental varieties (Monastrell, Cabernet Sauvignon and Syrah). The analysis were carried out by HPLC over two vintages (2024 and 2025), following the methodology proposed by Gómez-Alonso [1] with some modifications.

The results showed a lower synthesis of aminoacids in 2024 due to meteorological conditions. Even so, MS104 reached higher aminoacids amount in 2024 and Monastrell was not affected. Quípar, Myrtia, MS104, Carmolí, Monastrell, Cabernet and Syrah shown a particular aminoacids profile over the two studied seasons in contrast to Gebas and Calnegre in which there is no consistency over the two seasons. Concerning the fermentation performance, it was observed that Cabernet Sauvignon and Quípar were great proline accumulators, Gebas, Calnegre y Myrtia were medium proline accumulators and finally Monastrell, Syrah, Carmolí and MS 104 were low proline accumulators. About proline/arginine ratio, Cabernet Sauvignon reached the highest ratio, over 100, in contrast to Monastrell, MS 104, Myrtia and Syrah that were between 4.6 and 1.5.

In conclusion, the different grape varieties showed different characteristic aminoacids profile, which could affect the development of diverse aromatic characteristics in wines. Relate to the fermentation performance, Cabernet Sauvignon may require additional nitrogen due to its high proline-to-arginine ratio, whereas Monastrell, MS 104, Myrtia, and Syrah exhibited more favourable ratios that generally supported proper alcoholic fermentation. Even with this results, it is necessary to extend these studies over more years to establish stronger conclusions.

References

1. Gómez-Alonso, S.; Hermosín-Gutiérrez, I.; García-Romero, E. (2007). Simultaneous HPLC analysis of biogenic amines, amino acids, and ammonium ion as aminoenone derivatives in wine and beer samples. J. Agric. Food Chem., 55 (3) 608–613.