| Stomolophus meleagris (Jellyfish) is one of the most important fishery resources in China, which has the high economic, nutritional and medicinal value. It is widely distributed in China and it has a long history. However, there are still many problems in the traditional processing technology and the preservation of instant production of jellyfish. The content exceeding of Alum (Aluminum potassium sulfate) and preservation of instant products are problems greatly needed to solve.Ultrasonic wave and irradiation are respectively used in this study to improve the salting processing and the preservation of instant production of jellyfish. The following contents are studied:The effect of ultrasonic wave during the salting processing of jellyfish, the using of optimal ultrasonic wave technology in the improvement of jellyfish-salting. Studies of the desalination of instant production and the using of irradiation in the preservation of instant production are also studied. This paper aims to broaden the research field of jellyfish and provide a valuable scientific basis for the industrialization development of jellyfish.The main results are as follows:Firstly, biological characteristics of jellyfish and their processing status and ultrasonic technology and radiation technology are described.Secondly, the effect of ultrasonic processing technology during the salting of jellyfish is described. Different ultrasonic frequency, ultrasonic power and ultrasonic period is respectively studied during the salting of jellyfish. The optimal conditions are determined by single factor and orthogonal experiments. The results indicate that the optimal conditions are as follows:Ultrasonic frequency is 26.4kHz, ultrasonic power is 400W and ultrasonic period is per 5min/12h. Under these conditions, the quality of structure characteristic parameters of preserves such as hardness, elasticity and resilience are obviously increased, the number of microorganisms is obviously decreased. Ultrasound treatment can improve the quality of cured products of jellyfish, and at the same time it can effectively inhibit the growth of microorganisms.Thirdly, the improvement of traditional salting methods are studied. The optimal ultrasonic conditions are used in the improvement of processing technology. The results indicate that under this condition, the dose of alum is reduced to 80%, and the period is reduced to 13 days from 15days, which has a lower Alum residual than the commercial production. Microbiological test results show that the total number of microorganisms is inhibited under the 100CFU·g-1, and within the product shelf life (6 months), the total number of microorganisms has been under the 1000CFU·g-1, the pathogenic bacteria are not detected.Forthly, the research and development of new salting jellyfish and instant products are descripted, this chapter is divided into two parts:in the first part rehydration of salted jellyfish is studied. The main results are as follows:After Soaked in water(30℃, pH7.5)for 2 hours'rehydration, the percent of water is increased from 64% to 70%, and the percent of NaCl is reduced to 1.35% and alum reduced to 0.75%, while there is no significant change of the texture and content of solid-state protein. I n the second part, the preserved time of jellyfish is studied. Production is placed in water(60℃,40s) and dehydration of centrifuge(optimal conditions:4000r/min,5min).After vacuum packaging, the productions are exposed in irradiation for sterilization. The results indicate that the optimal conditions are as follows:Irradiation condition(5kGy,18h) gives the best preservation effects during the preservation of the following 180 days. the quality of institutions index the instant products are stability, and the solid-state protein content maintained at 78%, total number of microorganisms is under 1×103 CFU·g-1, the pathogenic bacteria are not detected, This paper provides a valuable scientific basis for the industrialization development of salted jellyfish.
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