Chinese prawn is a valuable seafood that is famous both at home and abroad. The annual catch of Shandong prawn generally accounts for more than 50% of the total catch of shrimp in the country, and ranks first in coastal provinces and cities. The maximum fishing output (1979) reached 22,000 tons.
The processed shrimps mainly include: frozen headed prawn, frozen headless prawn, frozen shrimp prawn, frozen tail prawn (Pterodactyl), and frozen butterfly shrimp. The method of freezing headed shrimp is mainly introduced. The other methods are basically similar.
1, pre-processing preparation:
a. According to the provisions of shrimp processing capacity configuration processing personnel, and in accordance with the provisions of their physical examination and technical training, learning the processing specifications, standards and related precautions.
b. Clean up, refurbish, wash and disinfect equipment and equipment required for processing.
c. Check the changing facilities, showers, toilets and disinfection facilities to meet the requirements. Equipped with complete work clothes, caps, sleeves, rubber shoes, aprons and other clothing.
d. Sanitary inspection of process water is used to ensure adequate water supply and meet sanitary requirements.
e. The necessary flushing of the cooling pipes in the quick-freezing room shall be carried out. The refrigerating rooms shall be sanitized and the refrigeration machinery and equipment shall be debugged to ensure the smooth production.
f. Clean up the processing room and packing room. Fly-flying, insect-proof, ventilation, lighting and other facilities in the workshop must be fully equipped, and the water pipelines must be unblocked.
g. Prepare adequate and qualified packaging materials and labels.
2, raw shrimp processing:
a. Acceptance and storage: After each batch of shrimps enters the factory, quality, hygiene, ice melting and packing are checked. In accordance with the requirements of the raw shrimp, should be processed in a timely manner, in order to achieve "the same day shrimp, the same day processing, the first time after the backlog." Raw shrimp that cannot be processed in time should be actively taken fresh-keeping measures, such as timely access to a fresh-keeping store at 0 to 4°C or a 1:3 ratio plus crushed ice below 3 cm. The ice cubes should be clean and the layers of ice shrimp spread evenly. Shrimp should be protected against fly maggots, light, rain, air drying and other pollution.
b. Rinse: Raw shrimps are rinsed with clean water that meets hygiene standards to remove crushed ice, sediment, seaweed and other contaminants.
c. Classification and selection: Washed shrimps should be primaries according to product quality standards, and separate raw materials such as prawn, headless shrimp, shrimp, and shrimp balls, and then process squid first, then process no head shrimp, and then process. Shrimp and shrimp balls are produced in the order of production. When sorting, raw shrimp should not be overstocked. When the temperature is high, add ice to keep it fresh. The selected shrimp body is placed in a clean container for preparation and processing separately. The yellow shrimp in the prawn and decapitated shrimp raw materials are separately stored and processed separately.
3. Processing of dry frozen headed prawn: The method of dry-sealing of headed prawn and large-scale cultured headed prawn is commonly used in seawater harvesting.
a. Process: There are scalp raw materials → washing → water control → weighing → dipping → water control → loading → freezing → refrigeration.
b. Process operation points:
Washing: The sorted shrimp raw materials should be carefully washed with clean fresh water, and the water should be cleaned every time.
Water control: The cleaned shrimps were placed in a clean sieve tray for 5 minutes.
Weighing: According to the specification of prawn, weigh out and sort out various specifications.
Dipping drugs: This process is carried out according to customer requirements. Generally, 1.25% sodium sulfite solution can be used. The shrimp body can be soaked in the solution for 1 minute and then washed with clean water for 15 seconds so that the residual sodium sulfite concentration does not exceed 10010 ↑ (-6), or 4% to 6% is used. Sodium phosphate solution, the shrimp body soaked for a few seconds, so that it forms a layer of glial film, in order to play a role in the seal, thus preventing water loss, to maintain the original freshness. Residues of sodium polyphosphate less than 0.5% are not harmful to human health. If no customer requirements can be omitted this process directly boxed frozen.
Cartoning: According to the packaging specification of head prawn, the prawn is put into a special small paper box, and plastic paper is put in the paper box. After the prawn is loaded, the plastic paper is folded up to cover the shrimp body, and then the lid is covered.
Freezing: Cartoned shrimps are immediately sent to the freezer and frozen to a temperature below -18°C.
Packing: Small boxes of shrimp are packed in big cartons, each containing 12 boxes. The names, specifications, weights, exporter's and company names, origins, and lot numbers are indicated outside the boxes. Such as spring shrimp plus brush "spring". Then feed into cold storage below -20°C.