Abstract
Aldehydes may be present in wines as a result of metabolic processes during wine fermentation or through oxidation and extraction from wood during wine aging in oak barrels. Apart from acetaldehyde, the most abundant aldehyde in wine, other aldehydes such as furfural and more recently vanillin have shown to contribute to the formation of more stable pigments. The copigmentation effect of phenolic molecules, including flavanols and anthocyanins themselves, has been previously evaluated in wine and model solutions, and even the effect of aldehydes related to wine aging has been documented at different pHs and molar ratios. The copigmentation phenomenon is observed by hyperchromic effects and bathochromic shifts of λ(max), and, in the same time, the presence of larger molecular weight pigments, potentially less susceptible to degradation, was followed up. This experimental work intended to evaluate the potential of five different aldehydes, all of which are safe for human consumption and are used in the food industry, to the formation of pyranoanthocyanin-like and polymeric pigments in the model solution.