1. Appearance is a signal, not the legal value
Clear oil can be a useful observation, but it does not directly state the percentage of polar compounds. Darkening and odour may also be affected by food particles, seasoning and oil type.
Use sensory observations as triggers for checking or replacement, not as proof that the oil is below the limit.
2. The 25% figure has a defined scope
Notification No. 283 says edible plant or animal oils and fats used to fry or cook food for sale must not contain more than 25% polar compounds by weight.
Notification No. 347 applies the same maximum to reused oil used by food producers for frying, coating, stir-frying or as an ingredient. It is an oil requirement, not a blanket certification of the finished-food lot.
3. A fry count cannot replace the result
Three or five uses do not describe cumulative time, temperature, food load, fresh-oil top-up, shutdowns or filtration. Different histories can therefore sit behind the same count.
A useful record follows the fryer or oil system and its actual conditions rather than recording an isolated tally.
4. Durian raw material changes the oil load
Ripeness, moisture, slice thickness, coating and fine particles can change the frying pattern and oil burden.
Thai origin context should connect supplier, orchard or collection source, receiving date and raw-material lot. A province name alone cannot replace test evidence.
5. Screening belongs inside a decision system
Thailand's Department of Medical Sciences published its PolarCheck screening innovation on 1 September 2026. Easier screening does not, by itself, create lot evidence.
An SOP should define sampling point, sample temperature, test-kit lot and storage, instrument checks, authorised readers, decision limits and confirmation for borderline or unusual results, following the real device's intended use and instructions.
6. Oil deterioration and acrylamide are separate controls
Polar compounds track oil deterioration. Acrylamide is a process contaminant associated with raw materials and heating. Passing one control does not prove the other has passed.
Keep separate evidence streams in the risk register, linked to the same lot identity and thermal history.
7. Seven-layer Reused Frying Oil Evidence File
This is an organising framework, not a standard or certification.
- Oil identity: type, supplier specification, lot and opening date
- Fryer history: equipment, vat, time, temperature, load and idle periods
- Food load: SKU, formula, slice size, moisture and debris
- Oil management: top-up, filtration, transfer and mix-up prevention
- Sampling trail: point, time, sampler, temperature and sample identity
- Measurement trail: device or kit lot, instructions, performance check, result and confirmation
- Decision lifecycle: warning rule, replacement or disposal, deviation, corrective action and review
8. Editorial and claim boundary
This article explains rules and evidence architecture. It is not a test result, legal opinion or ready-to-use SOP for a particular factory.
Siam Diamond Journal does not claim that Siam Diamond makes fried durian, reuses frying oil, owns a PolarCheck tool, has polar-compound results or has passed an inspection by any cited authority.
