COMPOSITION OF NATURAL FATS AND OILS 201 



Petroseliiiic acid (6,7-octadecenoic acid), which is an isomer of oleic 

 acid, is largely concentrated in the seed oils which belong to the family of 

 Umbelliferae. It has been shown to make up 60% of the total fatty acids 

 in fennel. It is found in such widely diverse umbelliferates as pars- 

 |gy^ 206,207 anise, -°^ carrot, celery, parsnip, chervil, caraway, fennel, and 

 coriander.'"* 



Erucic acid (13,14-docosenoic acid) is another unsaturated acid impor- 

 tant in such specific food fats as rapeseed oil. It is present to the extent of 

 40 to 57%-^""-^'" in this oil. Large amounts are also present in mustard- 

 seed oil {Brassica spp.), wallflower seed oil (Cheiranthus spp.),^^^ and Jamba 

 seed, or rocket salad oil (Eruca sativa) ,^^*--^^ and in the seeds from the 

 nasturtium (Tropaeolaceae). Nasturtium seed oil offers a good source of 

 erucic acid, since this acid makes up 80-90% of the total. ^^^'^^^ It is known, 

 furthermore, that 40% of the neutral fat consists of the simple triglyceride, 

 trierucin. Still another group of unsaturated fatty acids may be found in 

 the seed fats of the Flacourtiaceae. These consist of such acids as hydno- 

 carpic, chaulmoogric, and gorlic acids, all of which contain a cyclic penteno 

 group. Because of the reputed activity of chaulmoogra oil in the treat- 

 ment of leprosy, this group of acids has received considerable attention. 



Table 12 includes data on the composition of the fats containing these 

 unusual unsaturated fatty acids. 



(c) Fats Containing a Large Proportion of Saturated Short-Chain Acids. 

 In most cases the saturated acids comprise only about 10% of the fatty 

 acids of the vegetable fats. However, a somewhat higher content (15- 

 25%) of the saturated acids (chiefly palmitic) occurs in several plant fami- 

 lies such as Malvaceae (cottonseed), Solanaceae (tomato and tobacco), 

 Anacardiaceae (cashew and pistachio), and the Bomhaceae (kapok). Such 



206 T. P. Hilditch and E. E. Jones, /. Soc. Chem. Ind., 46, 174-177T (1927). 



207 E. Vongerichten and A. Kohler, Ber., 42, 1638-1639 (1909). 



208 Scherer, Dissertation, Strassburg, 1909. Quoted from T. P. Hilditch, The Chemical 

 Constitution of the Natural Fats, 2nd ed., Wiley, New York, 1947, p. 413. 



209 B. C. Christian and l'. P. Hilditch, Biochem. J., 23, 327-338 (1929). 



210 T. P. Hilditch and H. Paul, /. Soc. Chem. Ind., 54, 331-336T (1935). 



211 T. P. Hilditch, T. Riley, and N. L. Vidyarthi, /. Soc. Chem. hul, 46, 457-462, 462- 

 467T (1927). 



212 J. J. Sudborough, H. E. Watson, P. R. Ayyar, and N. R. Damle, J. Indian Inst. 

 Sci., A9, 26-43 (1926). 



213 T. P. Hilditch and E. E. Jones, J. Soc. Chem. Ind., 46, 467-469T (1927). 



21* H. P. Kaufmann and H. Fiedler, Fette u. Self en, 45, 299-302 (1938); Chem. Abst., 32 

 7756 (1938). 



216 J. J. Sudborough, H. E. Watson, P. R. Ayyar, and T. I. Mirchandani, /. Indian 

 Inst. Sci., A9, 52-64 (1926). 



216 T. P. Hilditch and M. L. Meara, /. Chem. Soc, 1938, 1608-1610. 



2" J. J. Sudborough, H. E. Watson, P. R. Ayyar, and N. R. Damle, J. Indian Inst. 

 Sri., A9, 65-66 (1926). 



