Effect of Key Technology on Texture of Ready-to-eat Crayfish in Soft Packaging

Abstract

In order to explore the effect of key technology on crayfish product quality, crayfish was used as raw material through texture analysis, low field nuclear magnetic resonance and sensory evaluation methods. The water-retaining agent (1%, 1.5% phosphate-free water-retaining agent and 1.2% sodium bicarbonate+4% trehalose), drying conditions (temperature: 70, 80, 90 ℃. Time: 0.5, 1, 1.5, 2 h) and sterilization conditions (100, 115, 121 ℃, 15 min) on its moisture, texture properties and sensory scores were researched, while to optimize the processing technology of flexible packaged ready-to-eat crayfish and explore the relationship between moisture and texture. The results showed that the addition of water-retaining agent (1.2% sodium bicarbonate+4% trehalose) increased the content of non-flowing water and free water in crayfish meat, significantly improved the water holding capacity of crayfish meat, and reduced crayfish meat hardness (P<0.05), and with the increasing of drying temperature and time, the moisture content of crayfish meat decreased significantly (P<0.05), and the hardness and chewiness increased. While too high sterilization temperature destroyed the internal fiber structure of crayfish meat, resulting in poor chewiness of crayfish meat. The results also showed that the water content of crayfish meat products significantly affected the quality of crayfish products, and the optimum processing conditions of ready-to-eat crayfish were determined, that was, the sensory quality of crayfish meat was better when adding water-retaining agent (1.2% sodium bicarbonate+4% trehalose) and drying at 70 ℃ for 1 h and sterilizing 15 min at 115 ℃, and increased pyrazine compounds which had the unique flavor of fried crayfish. The research results could provide theoretical reference for the quality improvement and industrialization of ready-to-eat crayfish in soft packaging.

Keywords

• crayfish
• water retention agent
• drying
• sterilization
• texture properties
• water distribution
• volatile flavor substances