CHEMICAL COMPOSITION OF WALNUT OIL FROM FRUITS ON DIFFERENT YEARS OLD BRANCHES

M. Stojanova, G. Uzunova, St. Gandev, M. Perifanova-Nemska

Abstract: The influence of the year of branches on the physico-chemical composition of walnut oil was investigated. There was an increasing of oil content with increasing the year of the branch found. The latter did not exhibit significant effect on fatty acid composition. All samples content predominantly unsaturated fatty acids - mainly oleic and linoleic acids. Linolenic was in the range of 9.66–10.77%. The highest content of polyunsaturated linoleic and linolenic acids was 64.14% and 10.77% respectively in fruits grown on four year old branch. The amount of tocopherols was the highest in the oil isolated from one year old branch - 567 mg kg-1. In tocopherol fraction of all tested oils γ-tocopherol dominates, followed by δ-tocopherol and α-tocopherol. The highest content δ-tocopherol was observed in the oil of one-year old branch - 9.7%. β-tocopherol was not found in studied walnut oils. The amount of the sterols was in the range of 0.5–0.7%. β-sitosterol dominates in sterol fraction - 86.2–89.8%.

Keywords: fatty acid; sterol; tocopherol; walnut oil

Date published: 2017-09-13