Critical Control Points in Potato Flakes Production¶
Company: Hongji Agriculture Co., Ltd.
1. Product Description¶
Potato Flakes is a cooked product in the form of snowflake flakes or powder, made from fresh potatoes that undergo acceptance inspection, storage, stone removal and washing, steam peeling, secondary washing, visual inspection, hydraulic conveying and slicing, blanching, cooling, cooking, mashing, drying, flaking and grinding, sieving, magnetic iron removal, weighing, packaging, and metal detection. The processing aims to minimize the destruction of potato cells and preserve the nutritional components as well as color, aroma, and taste.
2. Process Flow Chart¶
Receiving & Inspecting Potatoes (removing soil, dirt, foreign materials)
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Steam Peeling (0.8–1.5 MPa, 15–45 s)
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Dry Brush Peeling → Post-Washing → Visual Inspection → (Peel/Waste Disposal)
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Hydraulic Slicing (8–12 mm)
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Blanching (65–83°C, 15–35 min) → Cooling (≤30°C)
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Cooking/Steaming (Steam 0.3–0.4 MPa, 92–99°C, 15–45 min)
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Mashing (Additives: mono/diglycerides <0.5%, citric acid ≤0.01%)
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Drying (Steam 0.8–1.2 MPa, drum 120–240°C, moisture ≤9%)
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Flaking & Grinding → Sieving (16–40 mesh)
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Magnetic Separation ⚠️ CCP (magnetic force ≥8000 GS)
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Weighing & Packaging
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Metal Detection ⚠️ CCP (Fe≤1.5 / No-Fe≤2.4 / SUS≤3.0 mm)
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Storage and Dispatch
3. Detailed Process Parameters¶
| Process Step | Key Parameters |
|---|---|
| Stone removal & washing | Screw-type washing machine + stone remover; swirling water rinse; spray rinse |
| Steam peeling | Steam pressure 0.8–1.5 MPa, 15–45 seconds; PLC automated |
| Dry brush peeling | Nylon brushes; line pressure 0.8–1.5 MPa; compressed air 0.6–0.8 MPa |
| Visual inspection | Manual trimming of eyes, green/black parts, rot, residual skin, foreign materials |
| Hydraulic slicing | Water-jet slicing, 8–12 mm thick |
| Blanching | Steam + water mixture, 65–83°C, 15–35 minutes |
| Cooling | Counterflow cooling water, ≤30°C, 15–35 minutes |
| Cooking | Steam 0.3–0.4 MPa + atmospheric pressure, 92–99°C, 15–45 minutes |
| Mashing | Spiral feeder through mash screen (slow speed to prevent cell breakage) |
| Additives | Mono- and diglycerides < 0.5%; citric acid ≤ 0.01% |
| Drying | Steam 0.8–1.2 MPa, drum 120–240°C, film 0.2–0.25 mm, moisture ≤ 9% |
| Flaking & grinding | 4–8 mm snowflake flakes; grinding speed 10–40 Hz; sieve 16–40 mesh |
4. Critical Control Points (CCPs)¶
4.1 CCP-1: Magnetic Separation¶
| Item | Detail |
|---|---|
| Hazard | Physical (metal fragments) |
| Control point | Double-layer magnetic iron remover at vibrating sieve outlet |
| Critical limit | Magnetic force ≥ 8000 Gauss |
| Monitoring | QC checks magnetic strength every 10 days; replace magnets below 7000 Gauss |
| Operator cleaning | Every hour for first 3 hours, then every 4 hours; increase to hourly if debris > 3 mm appears |
4.2 CCP-2: Metal Detection¶
| Item | Detail |
|---|---|
| Hazard | Physical (metal fragments) |
| Critical limits | Fe ≤ 1.5 mm; No-Fe ≤ 2.4 mm; SUS ≤ 3.0 mm |
| Monitoring | Check detector sensitivity and proper functioning every 4 hours using test pieces |
| Corrective action | Alarmed products isolated for investigation and recorded |
5. Magnetic Iron Remover Maintenance¶
- Quality control checks magnetic strength every 10 days; replace magnets below 7000 Gauss.
- Operators clean magnets every hour for the first 3 hours of operation, then every 4 hours. If metal debris larger than 3 mm appears, increase cleaning frequency to once per hour until normal.
Cleaning Procedure¶
- Prepare clean cloth, alcohol spray, zipper bags, plastic tray, and 15 kg scale.
- Disinfect hands with alcohol spray.
- Zero the scale with the tray, weigh magnetic rods carefully.
- Clean impurities from the sleeve and rods with cloth and alcohol.
- After drying, reweigh and return rods.
- Collect debris > 3 mm in labeled zipper bags with date, time, shift, batch.
- Record pre- and post-cleaning weights and net weight in the magnetic rod cleaning log.
6. Packaging, Weighing, and Metal Detection¶
- Weighing: Sterilized bags coded and placed on packaging machine clamps; 25 kg ± 20 g net per bag.
- Date printing: Batch changes daily at 00:00; printing failures require on-site verification by supervisors and QC.
- Packaging: Composite inner bags + kraft paper outer bags; inner bag air removed and sealed with rubber bands; outer bag folded 4–6 cm and sealed by hand-held machine.
- Metal detection: Sealed products pass through a metal detector; qualified products sorted by batch, shift, and pallet number; alarmed products isolated for investigation and recorded.
This archive is part of the Hongji Agriculture Technical Documentation Series. For more information about our vertically integrated potato supply chain — from seed breeding and cultivation to processing and global export — visit our official B2B website: https://hjpotatoflakes.com
References¶
- ISO 22000:2018. Food Safety Management Systems.
- Codex Alimentarius. General Principles of Food Hygiene (CXC 1-1969).
- Hongji Agriculture Technology Co., Ltd. 2026. "Critical Control Points in Potato Flakes Production." Hongji Agriculture Knowledge Center.