Post-harvest compositional changes of yacon roots (Smallanthus sonchifolius Poepp. & Endl.) as affected by storage conditions and cultivar

POSTER - Yacon (Smallanthus sonchifolius Poepp. & Endl.; Figure 1) is a little-known native root crop of the Andes, which is typically cultivated in family gardens and field margins at altitudes between 1,500 and 3,200 m asl. The main constituent of yacon roots are oligofructans, which are polymers of fructose linked by ß-(2->1) glucosidic bonds, a carbohydrate the human body has no enzyme to hydrolyse. Therefore oligofructans are an ideal dietary sugar for diabetics. To increase the relative sweetness of the roots, these are preferably consumed after they have been exposed to the sun for several days. The juice of the roots can also be concentrated into a syrup. In recent years, rural farming communities began to extend the cultivation and processing of yacon to produce an alternative sweetener for the booming health food market. As oligofructans in yacon tend to depolymerise into reducing sugars (glucose, fructose, sucrose) fairly quickly after harvest, post-harvest compositional changes of the root are a concern to producers and processors alike.