Pre-Cooling Conditions
Room or forced-air cooling. Longan in plastic baskets can be hydro-cooled, although hydro-cooled longan should not be treated with SO2. SO2 fumigation damages hydro-cooled fruit skin by producing brown spots on both the inner and outer skin surface. It also results in greater SO2 residues remaining on the fruit (Suwanagul 1992). SO2 treatment of fruit to be sold as fresh is not approved in the U.S.