Free Fatty Acids in Shrunken‐2 Sweet Corn Seed

Abstract

High free fatty acid (FFA) levels have been reported in commercial shrunken‐2 (sh2) sweet corn (Zea mays L.) seeds. Objectives of this study included comparison of FFA content of sh2 corn seed with other genotypes and preliminary study of the source of the FFA. Kernel infection by seed‐borne fungi was not consistently correlated with FFA. With toluene extraction, sh2 sweet corn seed averaged 83.2 mmol kg−1 FFA compared with 2.1 mmol kg−1 from dent and 4.8 mmol kg−1 from sugary corn. Hot, water‐saturated butanol for 5 h (HWSB) extracted 57% more FFA from sh2 seed than did toluene. However, HWSB extracted 781% more FFA from dent corn seed than did toluene. Considering the four‐fold greater lipid content of sh2 kernels on a weight basis, this suggests that slightly more than half of the high FFA content of sh2 corn seed observed with toluene extraction resulted from relative lack of starch‐bound lipid in the sh2 endosperm.