Biogenic amines as an indicator of rye leaven quality during production and storage

Rye leaven, the basic constituent of sour rye soup ('żurek' or white borsch), was obtained through three methods of initiating lacto-fermentation of rye flour. Optimal concentrations of NaCl (1.5%) and garlic (0.5%) were selected by utilizing the response surface methodology. During the production and storage of leaven at 10 °C and 20 °C, the secalin proteins of rye flour degraded significantly and the concentration of free amino acids increased, making the rye leaven an environment potentially conducive to the formation of biogenic amines. Putrescine (max. conc: 116.7 mg kg^-1) and tyramine (max. conc: 63.4 mg kg^-1) were the amines that occurred in the largest amounts in the leavens. The final concentration of histamine (after 150 days of storage) did not exceed 22 mg kg^-1. Regardless of the method of initiation of fermentation, the products that contained fewer biogenic amines better retained their sensory characteristics (r ≤ -0.89, p < 0.05) and had a higher number of lactic acid bacteria (r ≤ -0.66, p < 0.05).