Composition of almond oil. III. Variation of several chemical and physico-chemical parameters during storage

Abstract

Tabulated data are presented on the variations in fatty acid composition, sterols, tocopherols, spectrophotometric indices and peroxide values during 3 yr storage of (i) sweet and (ii) bitter almond oils at 4° C or ambient temp. No differences in fatty acid composition were observed between (i) and (ii) but the sterol and tocopherol composition was different: (i) contained only alpha-tocopherol (45.8 mg/100 g), (ii) also contained gamma-tocopherol (34.5 mg alpha- + 11.3 mg gamma-tocopherol/100 g). During storage, the spectrophotometric indices and peroxide values rose while tocopherol contents fell (to 24.5 and 12.1 mg/100 g resp. in (i) and (ii) after 2 yr at 4° C, to 0 after 3 yr at 4° C or 2 yr at ambient temp.). Peroxide value in (i) rose from 9.6 to 21.3 after 1 yr, 29.6 after 2 yr and 129.5 after 3 yr at 4° C, with similar rises in (ii) and in spectrophotometric indices and much faster oxidative changes at ambient temp. [See FSTA (1980) 12 10N0471for part II.]