Key Quality Assurance Stages in a Toor Dal Plant:
- Raw Material Inspection: Selection of high-quality, matured, and properly dried raw Toor to ensure consistent milling quality.
- Cleaning and Pre-cleaning: Removal of foreign materials such as dust, stones, sand, and other debris using magnets, screens, and aspirators.
- Dehusking and Splitting (Milling): Modern milling techniques, such as dry milling or wet milling, are optimized to minimize breakage, with high-efficiency plants achieving 76-78% recovery of head pulses.
- Grading and Sorting: Using machinery for size grading to ensure uniformity. Color sorting (Sortex) is critical to remove discolored, damaged, or infested grains.
- Polishing (Optional): While some premium products are unpolished, others may be polished with edible oil or water to increase shelf life, or sometimes artificially with harmful agents like Metanil yellow (which QA must detect).
- Moisture Control: Ensuring the final product has a moisture level around 13-14% or lower (often <10% for export) to prevent fungal growth and spoilage.
- Packaging: Using, durable, moisture-proof packaging to protect against moisture and pests.
- Safety Testing: Regular laboratory analysis to check for adulterants (like Khesari dal), heavy metals, chemical residues, and to ensure nutritional consistency (approx. 22-24% protein).