Direct Treatment of Isada Krill under Subcritical Water Conditions to Produce Seasoning with Shrimp-Like Flavour

摘要

Characterization, sensory evaluation, and astaxanthin stability of isada krill under various subcritical water conditions were investigated to optimize the quality of krill extract and residue for producing food seasoning. Raw krill (82 % wet basis moisture content) without additional water was treated in a pressure-resistant vessel for 10 min at a temperature range of 100-240 degrees C. The yield of water-soluble protein was maximized by treatment at 200 degrees C and decreased with treatment at higher temperatures. The degradation of large molecules and the concomitant production of small molecules depended on the treatment temperature. Astaxanthin in the krill was unstable at temperatures higher than 140 degrees C. The odour intensities of krill extract and residue increased with higher treatment temperature; however, the highest intensity of pleasant shrimp-like flavour was obtained by treatment at 140 degrees C. Subjective preference scores were the highest for extract and residue obtained at 140 degrees C. Thus, treatment at 140 degrees C is the most promising method for production of seasoning with shrimp-like flavour from isada krill.