Research On Sterilization Technology Of Ultra-low Temperature Combined With Magnetic

With the improvement of living standards，more and more attentions are being paidto not only food hygiene, food safety but also food nutrition and sensory quality.Therefore, food sterilization technology has become the hotspot in the field of researchand application for food science. Meanwhile, how many nutrients as well as natural foodcharacteristics would be kept after sterilizing process is now becoming an importantindicator to evaluate sterilization technique. In this research, we study the effect ofultra-low temperature combinig with magnetic force treatment on survival rate ofmicroorganism. Then we came up with the optimal processing conditions, based onwhich we applied this new technology for bactericidal treatment on the instant shrimp tostudy the impact of such treatment on the texture of shrimp and theresults were as followed:1. Study on the sterilization effect of ultra-low temperature techniques on threedifferent microorganismsIn this research, bactericidal effect of ultra-low temperature was studied by treatingbacterial, mildew and microzyme under temperature of-60℃～100℃. Results showedthat, the optimal conditions were determined as treating them under-110℃for35minuteswith freeze-thaw circle for3times, through which sterilizing effect reached the best.2. Study on the sterilization effect of magnetic sterilization techniques on threedifferent microorganismsIn this research, bactericidal effect of magnetic force was studied by treatingbacterial, mildew and microzyme with different magneic intensity and processing time.The result show that: the optimal condition were determined as treating them withmagnetic intensity of380V for30minutes. Under such condition, sterilizing effectreached the best.3. Study on sterilization effect of ultra-low temperature techniques combinedwith magnetic sterilization techniques on three different microorganismsIn this research, bactericidal effect of ultra-low temperature combining magneticforce was studied by treating mildew and microzyme with different temperature, magnetic intensity and processing time. Results showed that, the optimal condition ofbacterials were determined as treating it under-110℃for35minutes together withmagnetic intensity of342V for20minutes, and the optimal condition of mildew andmicrozyme were determined as treating them under-100℃for35minutes together withmagnetic intensity of380V for20minute. Under such conditions, sterilizing effect ofreached the best.4. Research on application of sterilization technology using ultra-lowtemperature combining magnetic force in instant shrimp productBased on the research of fresh shrimp processing, the optimal processingparameters could be determined as followed: pre-blanching time to be60s,blanching time to be30s, concentration of color fixiative to be0.05%, dryingunder60℃for0.5hours during the first phase, drying under40℃for4.5hoursduring the second phase. Instant shrimps of cumin flavor or red alcohol obtainedwere much more popular. The application of ultra-low temperature combiningmagnetic sterilization treatment in instant shrimp helped ensure the products tomeet the national standards of food safety. Furthermore, according to data fromtexture analyzer, such sterilization treatment had no negative effect on shrimptexture.