 Then the lychee fruits are drained into a bucket for 4-8 hours at 10~15°C, then cool to 8-10°C and drain for another 10 hours.The sugar contents are adjusted to 22° Bx by dilution with water then mixing thoroughly together with 100mg/L sulfur dioxide and 80~120mg/L activated liquid pectinase.Freeze the treated lychee juice to get the condensed juice that is full of sweet and sour flavor.