Proximate and Amino acid Analyses of Full-fat Sunflower (Helianthus annuus L.) Seed Meal

Abstract

Whole sunflower seeds (raw and roasted) were analyzed for proximate and amino acid composition. Proximate analysis of sunflower seeds were carried out according to standard procedures and the amino acid compositions of the samples were determined using the Technicon Sequential Multisample Amino acid Analyzer (TSM). The range of values obtained from the proximate composition of sunflower seeds were; for dry matter (96.64-98.43%), crude protein (18.70-20.07%), crude fat (23.98-24.86%), crude fibre (11.81-12.92%), ash (3.36-4.98%) and nitrogen free extract (36.71-37.68%). The crude fat content of sunflower was high as showed in the results. The results on amino acid profiles of raw and roasted sunflower seeds showed that the concentrations of most of the amino acids were actually increased with heat processing with the exception of proline, glycine, alanine, cystine, valine, methionine and isoleucine. Glutamic acid had the highest concentration of 13.98 g/16 gN in the raw seeds and 14.83 g/16 gN in the roasted seeds. The first limiting amino acid was found to be methionine with values of 1.22 g/16 gN and 0.79 g/16 gN in the raw and roasted seeds respectively. The second limiting amino acid was cystine (1.48 g/16 gN in the raw seed and 0.89 g/16 gN in the roasted seed). Arginine had the highest concentration among the indispensable amino acids with the value of 6.97 g/16 gN and 7.31 g/16 gN in the raw and roasted seeds, respectively. The concentrations of lysine in the sunflower seeds were also relatively high (4.91 g/16 gN for the raw seeds and 5.57 g/16 gN for the roasted seeds).