Effect of inoculation strategy with autochthonous Oenococcus oeni strains on aroma development in Rioja Alavesa Tempranillo wines

Abstract

The potential use as malolactic starters of four indigenous strains of Oenococcus oeni was evaluated under different inoculation regimes. Among others, the fermentative capacity of strains, their degree of implantation, the main oenological parameters as well as their ability to modulate the aromatic profile of wines, were analysed. Main results elucidated that co-inoculation led to the prompt consecution of malolactic fermentation (MLF), highlighting the performance of indigenous Oenococcus oeni P2A strain and commercial O. oeni Viniflora OENOS strain which finished the process 20-30 days earlier compared to batches that undergo sequential inoculation. Moreover, inoculation strategy did also have an important influence on the volatile profile of wines. Coinoculated wines significantly showed less concentration of volatile compounds. Main reduction was detected in higher alcohols and acids. Lower concentration of acids and higher alcohols may prevent the masking of desired aroma attributes. Indeed, in co-inoculated wines, the perception of ripe fruit aroma was highlighted over the others, and was extensively perceived by panellists in comparison with their respective sequentially inoculated wines. Above all, it was elucidated the suitability of the strain P2A, resulting an advantageous alternative to significantly reduce the overall winemaking time as well as to better control the fermentative process.