Effect of long-term storage on dietary fibre in different cultivars of carrots

The effect of refrigerated long-term storage (six months) on dietary fibre in raw carrots was investigated in twelve cultivars representing five different groups. In three of the cultivars the viscosity of water-soluble fibre polysaccharides was analysed as well. Further, the bulking capacity of eight cultivars was evaluated through balance experiments in rats. A decrease of certain dietary fibre components was generally observed after six months' storage. Thus, there was a considerable reduction of unsoluble fibre polysaccharides containing galactose, and in the soluble fraction of galactose and arabinose containing polymers. Simultaneously there was an increase of glucose- (cellulose) and uronic acid- (pectin) based fibres, probably due to losses of components other than dietary fibre, e.g. low molecular weight carbohydrates. This may also explain the apparent higher amount of total fibre, calculated on a dry-weight basis, generally obtained after storage. The proportion of soluble fibre as well as the viscosity of the soluble fibre polysaccharides were only slightly affected by storage. Furthermore, faecal weights and dry matter digestibilities were very similar