Astaxanthin Extract from Shrimp (Trachypenaeus curvirostris) By-Products Improves Quality of Ready-to-Cook Shrimp Surimi Products during Frozen Storage at −18 °C

The effects of astaxanthin extract (AE) from shrimp by-products on the quality and sensory properties of ready-to-cook shrimp surimi products (RC-SSP) during frozen storage at −18 °C were investigated. Changes in 2-thiobarbituric acid reactive substances (TBARS) value, sulfhydryl groups, carbonyls, salt-soluble protein content, textural properties, color, and sensory quality over specific storage days were evaluated. The AE from shrimp by-products contained 4.49 μg/g tocopherol and 23.23 μg/g astaxanthin. The shrimp surimi products supplemented with 30 g/kg AE had higher redness values and greater overall acceptability and texture properties after cooking (p < 0.05). AE showed higher oxidative stability in RC-SSP than the control, as evidenced by lower TBARS and carbonyl content, and higher sulfhydryl and salt-soluble protein content. AE from shrimp by-products had positive effects on the antioxidant activity and color difference of RC-SSP, and could be used as a potential multifunctional additive for the development of shrimp surimi products.