Longan is a seasonal fruit commonly sold in summer. After harvesting, farmers or food manufacturers may treat longan with chemicals to prolong it's shelf-life. Sulphur dioxide is one of the chemicals used to prevent skin browning and post-harvest disease of longan. This treatment is a common practice in some countries, like Thailand and China. However, exposure to sulfur dioxide may cause allergy 1 in susceptible individuals. To reduce intake of sulfur dioxide, the following precautionary measures should be undertaken.
When we buy longan:
- Buy longan only from reputable shops
- Avoid buying longan with unreasonably low price
When we store longan:
- Separate longan from other food, like raw meat, to prevent cross-contamination
- If refrigeration is applied, consume refrigerated longan within 2 weeks
- If refrigeration is not applied, consume longan within a few days
When we eat longan:
- Discard any damaged longan
- Wash longan thoroughly and gently rub longan under running water before eating
- Avoid washing more than enough longan in one go
- Avoid biting the husk of longan
- Wash hands thoroughly after handling longan and before eating
- After removing the husk, eat the flesh as soon as possible
- Avoid eating too much and take a balanced diet
When we handle leftovers:
- Discard any flesh left out at ambient temperature for more than 2 hours
- Refrigerate and consume the flesh as soon as possible
1. Sulphur dioxide can induce allergic reactions like asthma in some individuals.
Photos are provided by Consumer Council