The aim of this study was to optimize the conditions for subcritical water treatment of krill, as expressed with a single parameter: the severity factor (logR0). Raw krill was treated under subcritical water conditions at various logR0 values (1.54-3.75) by varying the treatment temperatures (120-180°C) and times (0-10min) in two different sizes of batch-type vessel (10 and 117mL). The logR0 value could efficiently describe changes in various properties of the obtained liquid extracts and solid residues. The most desirable shrimp-like flavor intensity and highest sensory preference were obtained for logR0 values of 2.75-3.01. The results also proved that severity factor can be used as a single parameter to control subcritical water treatment conditions in differently sized batch-type vessels to produce shrimp-like flavor extract and residue from krill.