Information om Aprikoskärnor

Table 1 summarizes the chemical constituents of apricot kernels. The reported protein content of apricot kernel ranged from 14.1 to 45.3% (2,4,6,7,14–18). A PAGE study found that apricot kernel proteins contain 84.7% albumin, 7.65% globulin, 1.17% prolamin, and 3.54% glutelin. Nonprotein nitrogen is 1.17%, and other proteins are 1.85% (7). Research on the physicochemical properties of proteins revealed a UV absorption (lmax) of 282 nm; a fluorescence spectrum (emissionmax) of 315 nm; and four subunits with molecular sizes of 58,600, 37,400, 25,200, and 16,500 based on SDS-PAGE(19).

Table 1

Table 1

Essential amino acids in apricot kernel constituted 32–34% (15) of the total amino acids. The major essential amino acids (mmol/100 g meal) were arginine (21.7–30.5) and leucine (16.2–21.6), and the predominant nonessential amino acid was glutamic acid (49.9–68.0) (4).

Carbohydrate content of apricot kernel was reported variously as 25.5% (w/w) (20), 17.3% (6), and 18.1–27.9% (4). The total sugar content was reported as 4.10% in undefatted kernel and 7.76% in defatted kernel (7). Invert sugar content was 5.86% (10). The sugar content of kernels from different cultivars in Turkey is presented in Table 3 (14). The oil content of the kernels (Table 1) varies from 27.7 to 66.7% (2,4,6–8,14,15,17,18). Table 4 indicates that the contents of the major FA are oleic (58.3–73.4%) and linoleic (18.8–31.7%) (6–8,14,17,22–26). The contents of unsaturated FA (91.5–91.8%) and saturated FA (7.2–8.3%) (10,14) have been reported, as well as neutral lipids (95.7–95.2%), glycolipids
(1.3–1.8%), and phospholipids (2.0%) (10). The kernel oil contains 11.8 mg/100 g campesterol, 9.8 mg/100 g stigmasterol, and 177.0 mg/100 g sitosterol (27).

The values for specific gravity, refractive index, iodine, saponification number, and unsaponifiable matter for apricot kernel oil are presented in Table 5. The ranges are 0.1–1.6 for unsaponifiable matter (4,10,28,29), 187.3–199.0 for saponification number (12,21,28), 90.0–104.8 for iodine value (8,10,21,28,29), 0.876–0.932 for specific gravity (8,12,21,28), and 1.464–1.480 (8,10,21) for the refractive index.