Lipids in dried Moroccan Leguminosae seeds; a comparative study of 4 extraction methods

Abstract

Dried kidney beans, field beans, lentils, chick peas and peas were extracted by 4 different methods: (i) Soxhlet extraction with diethyl ether; (ii) extraction according to Folch et al. (3 successive extractions with 2:1 chloroform:methanol); (iii) 1:1 diethyl ether:petrol ether after acid hydrolysis at 75° C (ADAC method); and (iv) extraction as in (i) after acid hydrolysis at 100° C. Tabulated results showed erroneously high values for crude fat by method (iii); highest values for total fatty acids by method (iv) and equal slightly lower, values by (ii) and (iii); total triglycerides ranged from 0.31 to 4.24 (chick pea) total phospholipids from 0.54 to 0.67 mg fatty acid/100 g seed, and triglyceride:phospholipid ratio from 0.46 to 6.95 (chick pea). The main fatty acids in decreasing order were linoleic (46.1-57.6%), oleic (20.6-28.5%) and palmitic acid (9.9-16.9%) except for kidney beans with 40.4-52.6% linolenic, 26.9-27.7% linoleic and 9.9-19.9% palmitic acid.