Detailed Explanation of Key Technical Points in the Quick-Freezing Process for Exported Shrimp Meat

1. Process flow

Raw material acceptance → Raw material storage → Raw material thawing → Shrimp peeling → Acceptance → Washing → Soaking → Blanching → Cooling → Size grading → Freezing → Ice glazing → Metal detection → Boxing → Refrigerated transport

2. Operational key points

2.1 Raw material acceptance QC (quality control team) must inspect quality to prevent blackened shrimp. If blackened shrimp are found, promptly report back to the importer for handling. Keep a "Raw Material Acceptance Record" for each batch of raw materials.

2.2 Raw material storage: Store by container batch number at below -18°C. Temperature must be strictly controlled to ensure raw material quality.

2.3 Raw shrimp thawing: Thaw with running water, generally for 1.5h, but note that in summer the shrimp must not be completely thawed, to prevent blackening caused by excessively high temperatures. At the same time, maintain the temperature at <25°C, mainly using air conditioning to control the temperature.

2.4 Shrimp peeling: Pay attention to the shape of the shrimp body; do not cause man-made defects such as broken pieces or broken tails. Peeled shrimp must have the sand vein removed, and foreign matter must also be checked for.

2.5 Acceptance: Dedicated personnel must carry out acceptance and pay attention to product quality. (No foreign matter, shrimp legs, shrimp shells, shrimp whiskers, residual sand veins, etc.) QC personnel must conduct random inspections promptly, keep "Acceptance Records", and require workers to rework non-conforming products until they meet the specified requirements.

2.6 Washing: Wash with running water (stir by hand 20 times), soak in ice water (<5°C) for 10s (seconds), then soak in disinfectant water for 10s, then rinse twice with clean water, and finally wash once with running water. Operators must change the water after washing each basket as required. The purpose is to wash away impurities adhering to the surface of the shrimp meat.

2.7 Soaking: Each barrel contains 200kg shrimp meat, 100kg ice, 100kg water, 5.6kg salt, and 5kg shrimp treatment; the soaking time is 18h, and a dedicated person must stir once every hour: ① to make the shrimp meat soak thoroughly; ② to prevent the shrimp meat from heating up and developing off-flavors. Add ice promptly according to the degree of ice melting, and use air conditioning to control the temperature of the quasi-hygienic zone, maintaining the temperature at <8°C.

2.8 Blanching: Blanching machines generally use steam heating, with the temperature controlled at (98±2)°C and a blanching time of 3~5s, which should be determined according to the size of the shrimp. The blanching water must be changed every 2h. After blanching, the odor should be normal, with no undesirable off-odors, and the muscle should be firm and elastic. It should have the inherent fresh flavor, texture, mouthfeel, and elasticity of this type of shrimp.

This process is completed by QC; every barrel of shrimp meat must be evaluated once to ensure that the product quality passes after sale and does not lead to customer complaints.

2.9 Cooling: Cool with running water; as with blanching, change the water every 2h to prevent an increase in microorganisms. At the same time, control the cooling water temperature at <16°C, then soak in ice water (<5°C) for 20s, and finally cover with ice to ensure the shrimp body temperature is sufficiently low.

2.10 Size grading and sorting: Specification refers to the number of center tails per pound. The number of shrimp tails contained in different specifications is detailed in Table 1.

Table 1 Comparison table of shrimp tail counts for different specifications

Specification MLML2LM

Tail count 270220170130

Specification 2L3L4L5L

Tail count 105857060

Specification 6L7L8L9L

Tail count 50403020

2.11 Freezing: Station 6 people at the feeding port: 1 person to wash the material, 1 person to pour the material, and 4 people to spread the material. At the same time, sort out defective products and foreign matter. The freezing temperature is -24°C~-31°C, and the center temperature of the frozen product is -18°C.

2.12 Ice glazing: The temperature of the ice-water mixture is 0°C~3°C, the draining time is 2~3s, and the workshop temperature is <25°C.

First ice glazing: ice glazing rate 13%~14%; second ice glazing: ice glazing rate 26%~27%.

2.13 Metal detection: Detect each bag without omission. Every 0.5h, QC must test the machine with a metal test piece and keep a "Metal Detector Record".

2.14 Boxing: Each box contains 10 bags, each bag 1kg, and the batch number, production date, and best-before date must be marked.

2.15 Refrigerated transport: Store and transport at below -18°C, and ship promptly.