Effect of Secondary Sterilization on the Quality of Roasted Whiteleg Shrimp（Litopenaeus vannamei）

摘要

This study was carried out to investigate the effects of secondary sterilization on the quality of roasted shrimp( Litopenaeus vannamei)with high nutrients. Roasted shrimps were vacuum packaged, with 100 g in each bag, and subjected to secondary sterilization for 30 min at 70, 80,90, 100, 110 and 120 ℃, or for 10, 20, 30, 40 and 50 min at 90℃. Then, the color, textural properties, sensory quality and pH were measured, and whether they were commercially sterile was evaluated. The results showed that with the increase of sterilizing temperature, L*, a*and b*values all decreased. And with the increase of the duration of sterilization, L*slightly decreased, while a*and b*slightly increased. In addition, with the increase in sterilizing temperature, the hardness, gumminess, chewiness and springiness of roasted shrimps increased at first and decreased subsequently, while the adhesiveness kept increasing, and the cohesiveness and shear force slightly declined. With the increasing duration of sterilization,the hardness, adhesiveness and chewiness rose, the cohesiveness and shear force declined, the gumminess decreased at first and increased subsequently, while the springiness increased at first and decreased subsequently. The pH of roasted shrimps varied in a complex pattern when sterilizing temperature was increased, but increased with the increasing duration of sterilization. The results showed that the roasted shrimps secondarily sterilized at 90℃ for 30 min have the best sensory quality, and are commercially sterile.