The role of hot and cold tanks in the production of seafood sauce

To produce hoisin sauce, the following equipment is required: a steamer, mincer, hot and cold vats, roller mill, filling machine, sealing machine, and an ultra-high temperature instant sterilizer.

The key ingredients include white sugar, soybeans, slag water, rice, vinegar, garlic, soy sauce, MSG, oil, and sodium benzoate. The production process involves several critical control points:

1. **Ingredient Preparation**: Add vinegar, oil, and soy sauce at the start of cooking. Crush garlic and mix it with bean curd residue, passing it through a grinder with water before adding it to the cooking pot.

2. **Cooking Process**:

- Add sugar when the mixture reaches above 70°C.

- Introduce sodium benzoate and MSG 5 minutes before the end of cooking.

- Control the temperature rise rate to 1.5°C/minute from the start of ingredient addition to boiling.

- Maintain boiling for 45 minutes at a steam pressure of 0.20–0.25 MPa, using a reflux pump to circulate the sauce while keeping the pot lid closed.

3. **Grinding and Cooling**: Ensure the sauce is finely ground with no graininess. Cool it to 65°C in stainless steel hot and cold tanks before filling.

4. **Filling and Sealing**:

- Securely close lids during filling.

- Return any leftover sauce to the pot for re-cooking.

- Limit the net weight to 500 grams per can, ensuring cleanliness and proper sealing to prevent leakage.

5. **Labeling and Packaging**:

- Ensure clear and accurate inkjet printing and labeling.

- Match carton labels with can labels for consistency.

**Cleaning Procedures**:

- **Pre-production**: Clean equipment and pipes with tap water for 20 minutes, followed by boiling water at ≥90°C for 10 minutes.

- **Post-production**: Clean equipment and pipes in sections, rinsing with tap water for 5 minutes, then disinfecting with a 1/1000 sodium hypochlorite solution, soaking overnight.

**Quality Requirements**:

- Color: Dark brown

- Aroma: Rich sauce flavor

- Flavor: Slightly sweet

- Solids content: >50%

- Total bacterial count: <100 cells/100 ml

This process ensures the production of high-quality hoisin sauce with consistent flavor, aroma, and safety standards.