Key operating steps and precautions for the production line of hard biscuits.

The hard biscuit production line is a highly efficient automated equipment specifically designed for the production of hard biscuits, and is widely used in the food processing industry. It features a novel design, compact structure, and high degree of automation, completing the entire process from feeding to rolling, shaping, waste recovery, drying, oil spraying, and cooling in one continuous operation. The main equipment of the production line includes a dough mixer, forming machine, control cabinet, baking oven, oil spraying machine, and cooling machine. The dough mixer is used to uniformly mix the raw materials; the forming machine uses molds to shape the dough into various biscuit shapes; the baking oven uses a mixed heating method (direct combustion and hot air circulation), with automatic constant temperature and pressure control to reduce energy consumption, and is equipped with safety protection devices such as emergency stop switches and automatic alarms; the oil spraying machine evenly sprays oil onto the biscuits; and the cooling machine quickly cools the biscuits for easy packaging.
Key operating steps and precautions for the hard biscuit production line:
1. Dough Mixing and Processing
Low-temperature mixing:
Use a constant-temperature dough mixer (temperature ≤20℃) to prevent the fat from melting and causing the dough to become too soft.
Mixing time should be controlled between 8 and 15 minutes, until the dough is smooth and does not stick to the mixing bowl.
Resting and relaxation:
The dough needs to rest for 20-30 minutes, covered with a damp cloth or plastic wrap to prevent the surface from drying out.
Rolling and folding:
The dough is rolled into a uniform thin sheet (3-8mm thick) using a roller press, and repeatedly folded 3-5 times to form a multi-layered structure.
Ensure consistent rolling speed and thickness to avoid dough shrinkage or breakage.
2. Forming and Stamping
Stamping machine operation:
Adjust the mold pressure to ensure clear and undeformed stamping, and promptly recycle and reuse the scraps. Regularly clean the molds to prevent dough residue from affecting subsequent shaping.
Roller cutting machine operation:
Adjust the cutting blade spacing to ensure uniform biscuit size (error ≤ 1mm).
Check the conveyor belt speed to prevent biscuits from sticking together or overlapping.
3. Baking and Cooling
Oven parameter settings:
Temperature: Upper layer 220~250℃, lower layer 200~230℃ (hot air circulation mode).
Time: Adjust according to biscuit thickness (5~15 minutes), until the surface is golden brown and the inside is thoroughly cooked.
Check the baking status every 15 minutes to avoid localized burning or undercooking.
Cooling treatment:
Immediately transfer to a cooling tunnel (air cooling or natural cooling) after baking to prevent residual heat from causing the biscuits to soften.
Cool to room temperature (≤30℃) before packaging to prevent moisture accumulation inside the packaging.
4. Packaging and Quality Inspection
Automated packaging:
Adjust packaging machine parameters (such as sealing temperature, cutting speed) to ensure good packaging sealing.
Regularly check the quality of the packaging film to avoid leaks or damage.
Online quality inspection:
Use metal detectors and weight sorters to remove unqualified products (such as metal impurities, broken biscuits).
Manually sample and inspect the appearance (shape, color, cracks) and texture (crispness).