The photocatalytic sterilization and preservation performance of riboflavin-sensitized TiO2 nano-composite photocatalyst (TiO2@rib) on peeled Pacific white shrimp.

A riboflavin-sensitized food-grade TiO2 composite photocatalyst (TiO2@Rib) was synthesized. The sensitization extended its light absorption into the visible region and narrowed the bandgap to 2.36 eV. TiO2@Rib possessed excellent water solubility (∼4868 μg/mL). TiO2@Rib exhibited a high capacity for generating singlet oxygen and hydroxyl radicals. Refrigerated shrimp treated with TiO2@Rib achieved the highest sensory evaluation score. It effectively suppressed the increase in the freshness indicators during storage, including total volatile basic nitrogen (29.88 ± 0.20 mg/100 g), pH (7.81 ± 0.09), total viable count (5.67 ± 0.03 log CFU/g), and malondialdehyde (166.12 ± 2.28 nmol/g) on day 6. It also effectively inhibited the oxidation of proteins and lipids, with total protein and sulfhydryl contents of 16.03 ± 1.15 mg/g and 0.092 ± 0.002 mmol/gprot, respectively. Additionally, water loss in refrigerated shrimp was effectively restrained. Therefore, TiO2@Rib-mediated photocatalytic sterilization and preservation extended the refrigerated shelf-life of shrimp to 6 days.