Radio frequency-assisted hot air drying of pacific white shrimp ( Litopenaeus vannamei ): drying kinetics, product quality and composition evaluation

The influence of radio frequency-assisted hot air drying (RFHAD) on the drying kinetics, product quality and composition of Pacific white shrimp was evaluated and compared with radio frequency drying (RFD) and hot air drying (HAD). The results demonstrated that RFHAD showed faster drying rate and also ensured better product quality in terms of texture property, astaxanthin content, color quality, rehydration rate and microstructure of shrimp. Furthermore, RF wave could significantly reduce the formation of bitter amino acids (p < .05) and showed no significant difference in the content of umami amino acid. However, secondary structure changes were observed in RFHAD shrimp with a decrease in β-sheet and α-helix contents and increase in β-reverse fold, and RFHAD noticeably decreased the onset temperature, peak temperature and thermal enthalpy (ΔH) values of shrimp, which showed lower thermal stability. Therefore, the RFHAD method is a fast and efficient drying technology for shrimp with high-quality characteristic.