Influence of different levels of sodium chloride and of a reduced-sodium salt substitute on volatiles formation and sensory quality of wheat bread

The influence of sodium chloride or of the reduced-sodium salt substitute Pansalt® (NaCl 57%, KCl 28%, MgSO4 12%, lysine hydrochloride 2%, silica 1%, iodine 0.0036%) at two addition levels, 1.5% and 3% (on flour weight), on volatiles formation and sensory profile of yeasted wheat bread was investigated. Volatiles were determined by HS-SPME/GC-MS. An increased level of NaCl was associated to a reduced formation of 2-phenylethanol, a key odorant contributing to a yeast-like note. In contrast, at the 3% NaCl level the formation of most of Maillard reaction volatile products was promoted. Accordingly, sensory analysis highlighted a less intense yeasty note in the crumb, as well as more intense toasted aroma and flavour in the crust of bread with 3% NaCl with respect to the 1.5% counterpart. Bread with 3% NaCl was also characterized by more bitter crust and more even crumb structure. Increasing the addition level of Pansalt® from 1.5 to 3% produced similar effects on bread sensory attributes than NaCl. However, the substitution by Pansalt® was not able to maintain the same level of perceived saltiness as NaCl at both addition levels. In particular, Pansalt® at 3% produced a perceptible increase in bitter taste and aftertaste in the crust.