The experimentally cultivated potatoes of 4 varieties, Irish Cobbler, Warba, Shimabara, and Saco were dried in a frozen state, powdered subsequently and subjected to the extraction of free and bound lipids. Constituents of the prepared lipids were fractionated, quantified, and compared by the methods of column and gas-liquid chromatographies. The results were summarized as follows
1. The total crude lipid content in potato on a dry weight basis was 0.57 % of which 0. 2 % was free lipid and 0.37 % was bound lipid.
2. The neutral lipid content in the free lipid was 14.9 %, approximately 3 times as much as the 4.5 % contained in the bound lipid, whereas the glycolipid content in the free lipid was 15.1 %, slightly less than 22.2 % contained in the bound lipid. However, the phospholipid content was 33.9 % in the bound lipid, approximately 4.5 times as much as the 7.2 % contained in the free lipid. This fact revealed that the bound lipid consisted mainly of polar lipid, while the free lipid consisted of neutral lipids, glycolipids and phospholipids in about the same proportion.
3. The main fatty acids constituting more than 90 % in the free and bound lipids were linoleic, palmitic and linolenic acids. The content of the saturated fatty acid was slightly less in the free lipid than in the bound lipid, whereas the unsaturated fatty acids were more abundant in the free lipid.
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