There is provided a novel carbohydrate: having neither a carbon-carbon double bond nor a carbonyl group and represented by a molecular formula C6H10O5 showing a retention time of 11.0 +/- 0.2 minutes when maltose and fructose as reference materials show retention times of 8.8 minutes and 12.5 minutes, respectively, the retention times being measured by high performance liquid chromatography using a column having, as a filler, a strongly acidic ion exchange resin which is a styrene-divinylbenzene copolymer with a degree of crosslinkage of 8% and has a sulfonic group bonded to sodium as an ion exchange group, at a column temperature of 40 DEG C and a flow rate of water as an eluent of 1 ml/min and showing intramolecular carbon chemical shift values obtained by carbon nuclear magnetic resonance of 70.54 +/- 1 ppm, 95.37 +/- 1 ppm, 75.09 +/- 1 ppm, 68.86 +/- 1 ppm, 77.99 +/- 1 ppm and 64.15 +/- 1 ppm. This novel carbohydrate is useful as an antioxidant.
