Effect of Amino Acid, Sugar, Ca(2+), and Mg(2+) on Maillard Reaction-Associated Products in Modified Sparkling Base Wines During Accelerated Aging.

The Maillard reaction (MR) between sugars and amino acids, peptides, or proteins is understood to occur gradually during the production and aging of sparkling wines, where it contributes to caramel, roasted, and toasted aromas. Divalent metal ions can accelerate the MR, although this has not been previously reported in wine or wine-like conditions. In this work, the effect of calcium (Ca) and magnesium (Mg) ions on the concentration of 10 Maillard reaction-associated products (MRPs) was measured in modified sparkling base wine during accelerated aging at 50 °C for four weeks. Chardonnay base wine was modified by the addition of fructose (0.02 M) and a single amino acid (lysine, glycine, cysteine; 0.01 M) in combination with Ca(2+) or Mg(2+) at zero, low (10 mg/L), or high (50 mg/L) dose levels. MRPs were quantified by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC/MS), sugar concentration was measured by enzymatic assay, and amino acids and free metal ions were monitored by capillary electrophoresis. Fructose levels did not substantially decrease during aging despite increases in all MRPs, suggesting that trace sugars or α-dicarbonyl species present in the wine matrix likely play a greater role in MRP formation than fructose. Aging duration and amino acid content had a greater effect than metal addition on the composition of the MRPs. Treatments containing cysteine and 50 mg/L Ca(2+) had elevated concentrations of benzaldehyde and furfural ethyl ether following 4 weeks of accelerated aging. This work identified key MRPs that increase during base wine accelerated aging and informs future research on the relationship between wine composition and aging markers.