Differential consumption of malic acid and fructose in apple musts by Pichia kudriavzevii strains

Abstract

Aims: To assess the capability of Pichia kudriavzevii strains isolated from wine, cider, and natural environments in North Patagonia to produce ciders with reduced malic acid le v els. Methods and results: Fermentation kinetics and malic acid consumption were assessed in synthetic media and in regional acidic apple musts. All P. kudriavzevii strains degraded malic acid and grew in synthetic media with malic acid as the sole carbon source. Among these strains, those isolated from cider exhibited higher ferment ative capacit y, mainly due to increased fructose utilization; ho w e v er, a lo w capacity to consume sucrose present in the must was also observed for all strains. The NPCC1651 cider strain stood out for its malic acid consumption ability in high-malic acid Granny Smith apple must. Additionally, this strain produced high levels of glycerol as well as acceptable levels of acetic acid. On the other hand, Saccharom y ces cere visiae ÑIF8 reference strain isolated from Patagonian wine completely consumed reducing sugars and sucrose and sho w ed an important capacity for malic acid consumption in apple must fermentations. Conclusions: Pichia kudriavzevii vii NPCC1651 strain isolated from cider e videnced interesting features f or the consumption of malic acid and fructose in ciders.