Introduction to New Technology of Aquatic Products Processing (I)

1. Microwave Microwave is an electromagnetic wave, and its industrial heating frequency is 915 MHz and 2450 MHz.
Principle: In the external high-frequency alternating field, polar molecules such as water constantly twist and generate heat. Its characteristics are fast speed, uniform heating, energy-efficient, clean and hygienic, and strong heating selectivity. Its main uses are temperature thawing, heating and cooking, sterilization and disinfection.
Second, ozone ozone is allotrope of oxygen, at room temperature is a lavender gas, there is a slight odor, it is called ozone.
Principle: Ozone has extremely high oxidizing power and easily oxidizes lipoproteins in the cell wall of bacteria, thus destroying cells.
Features: Can be used in both air and water. Easy to operate, fast speed; good effect, no residue, good safety. For production water, aquaculture water disinfection, cold storage disinfection, sterilization and deodorization between processing. Equipment for ozone generator, photochemical, electrochemical, corona discharge method.
Third, high pressure sterilization pressure refers to 400 ~ 600 MPa of static pressure.
Principle: The cell deforms and breaks down at 600 MPa; the high pressure changes the conformation and passivation of the enzyme, and changes in the pressure response result in changes in the biochemical reaction.
Features: The flavor, nutrition and color of the processed product hardly change (cold sterilization), sterilization is completely uniform, and energy consumption is low. Application: The gel strength of surimi increases and the paste is bactericidal. The device is a high voltage generator.
4. Microcapsules Microcapsules are microcapsules with a diameter of 5 to 200 μm, and have micro-containers or packages of polymer wall shells.
Core material: gas-liquid-solid three-state, flavors, vitamins, minerals, preservatives, enzymes and other additives.
Wall materials: polysaccharides, proteins, glues and other macromolecules.
Features: Prevent oxidation, isolate active ingredients, control release (pressure, temperature, moisture, pH, etc.) and distribute evenly.
Preparation: spray drying, interfacial polymerization, molecular embedding.
Applications: Preservatives for fish products, sustained release ethanol, chewing gum, and open feed.
V. Frozen Association
1. Concentrate, dry, pulverize, thaw: The water in the dilute solution is frozen and the ice crystals are separated so that the solution is concentrated.
Features: It is good for heat-sensitive materials, avoids the loss of aromatic substances, better than evaporation, film concentration, and crystallization.
2. Freeze and crush: freeze the material below the freezing point and use the brittleness of the material to crush it.
Features: Applicable to oily materials containing more water (turtle), no deactivation phenomenon.
3. Drying (FD): The material is first frozen and removed under high vacuum conditions by direct conversion of ice to steam.
Features: Almost no biochemical denaturation, maintaining the original shape, conducive to rehydration.
4. High-pressure snap-freezing: The use of pressure release quickly passes through the maximum ice crystal formation belt, so as to achieve true quick freezing, and vice versa, high pressure rapid thawing can also be achieved.