超高压处理对冻藏南美白对虾理化指标及品质的影响

Effect of Ultrahigh Pressure Treatment on Physicochemical Indexes and Quality of White Shrimp(Litopenaeus vannamei) during Frozen Storage

以500 MPa保压5,10,20 min的南美白对虾为对象,研究其在-18℃贮藏过程中理化指标、水分含量、水分分布及存在状态和组织结构的变化。结果表明,贮藏期结束时,各组对虾理化指标(pH值和TVB-N值)均未超标;未经超高压处理的对虾头胸部出现黑变现象,超高压处理改善了对虾的外观和色泽;保压5 min和10min组对虾的硬度、弹性和水分状态变化小于保压20 min组,且这两组对虾水分损失更小,肌肉纤维排列较为致密。500 MPa/5 min和500 MPa/10 min的超高压处理条件较为合适,可适当改善对虾色泽、质地及组织结构。

The effect of ultrahigh pressure treatment of 500 Mpa for 5, 10, and 20 min on the physical and chemical indexes, moisture content, water distribution and organization structure of white shrimp Litopenaeus vannamei were investigated during frozen storage at-18 ℃. The results showed that the physical and chemical index were not exceed limits at the end of storage time;the cephalothorax shrimps untreated with ultrahigh pressure blacked during storage, the appearance and color of ultrahigh treated shrimps were improved;the changes of hardness, springiness, and water status of shrimps treated by 500 MPa/5 min and 500 MPa/10 min were less than shrimps treated by 500 MPa/20 min, and the two sets had less water loss and dense muscle fiber arrangement. As a result, ultrahigh pressure treatment by 500 MPa/5 min and 10 min 500 MPa were suitable processing conditions for shrimps for the improving of color, texture, and organization structure.