Lychee Safety Inspection
Detect artificial colors, sulfur treatments, and growth chemicals in Lychees
Inspection Guide
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Lychee Purity Inspection Guide
Lychees are often treated with dyes or sulfur to maintain their bright red appearance.
1. The Dye Rub Test: Use a wet white tissue or cotton ball to rub the surface of a bright red lychee. If pink/red color transfers, it is artificially dyed with Rhodamine B.
2. Water Bleed Test: Soak lychees in a bowl of water for 5 minutes. If the water turns pinkish or reddish, the fruit has been colored.
3. Aroma Check: Smell the fruit. A natural sweet scent is safe. A pungent, sulfurous, or chemical smell indicates sulfur dioxide treatment or chemical ripening.
4. Skin Texture: Natural lychees are bumpy and slightly rough. An unnaturally glossy, oily, or waxy coating may indicate a chemical wash to prevent dehydration.
Quick Safety Tips
- Rub with wet cotton to check for artificial dyes
- Soak in water - check for color leaching
- Avoid unnaturally bright, neon-red fruits
- Reject fruits with a chemical or sulfurous odor
What CANNOT be Verified (Lab-Only)
Invisible Risks (Lab-Only):
* Pesticide Residue: Modern pesticides used in lychee orchards can only be detected via GC-MS or HPLC analysis.
* Sulfur Dioxide Levels: While high levels are detectable by smell, low residual amounts require specialized chemical titrations.
Chemical Concerns
Step 1: AI Visual Scan
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