No. Plucked yam sugar sand is not boiled for a long time, the reason for simmering plucked sugar turned sand is mainly because the sugar is not completely dissolved, the following heating when the bottom layer of sugar all burned, but a part of the sugar did not receive the temperature, in the sugar syrup to move back and forth, so the boiled sugar is transparent. Yam, Dioscorea spp. of the family Dioscoreaceae. Yams are twining herbaceous vines of the genus Dioscorea in the family Dioscoreaceae. The tubers are long and cylindrical and grow vertically. Stem usually purplish-reddish, right-handed, glabrous. Leaves are simple, alternate in the lower part of the stem, opposite above the middle. Male inflorescence a spike, 2-8 cm long, suberect, 2-8 inserted in leaf axils. Capsule not reflexed; seeds inserted at middle of each locule. Flowering June-September, fruiting July-November.