Abstract
The relationship between cooking properties of different varieties of potato (Solanum tuberosum), Danshaku and Meikuiin, and their structure of non-starchy polysaccharides including cell wall polysaccharides was investigated.
Non-starchy polysaccharides were fractionated by successive extractions with water, hot water, 0.5 % ammonium oxalate, 5 % sodium hydroxide, 24 % potassium hydroxide and 90 % dimethyl sulfoxide.
When compared these two varieties of potato, the proportion of pectic substances, water-, hot water- and ammonium oxalate-soluble polysaccharides, showed higher in Danshaku and that of hemicellulosic substances, alkali-soluble polysaccharides, showed higher in Meikuiin.
The results of the structural investigation of water-soluble polysaccharide were reported.
Water-soluble polysaccharide from Meikuiin contained two kinds of α-1→6 glucan and that from Danshaku consisted of complicated structural polysaccharides, which have 5- linked-arabinose, 2-linked-rhamnose, 4-linked-galactose and 2, 6-linked-galactose residues.
Dextran-like polysaccharides obtained from Meikuiin can play an important role in preventing breakdown of potato tissues during cooking.
