Sains Ma1aysiana 26(2): 43-51(1997)                                                                                            Sains hayat/

                                                                                                                                                                 Life Sciences

Effect of Irradiation on Lipid Characteristic of Plant Nuts

Anwar Ahmad Sattar

Nuclear Institute for Food and Agriculture (NIFA) Peshawar

Altaf Hussain

Nuclear Institute for Agriculture and Biology

Faisalabad, Pakistan

Mohammad Zafar Iqbal

of Chemistry University Of Punjab

Lahore, Pakistan

ABSTRACT

Different plant nuts were irradiated with gamma rays to dose levels of 0.5, 1.0 and 1.5 kGy. Total lipids of the treated and untreated samples of plant nuts such as almond, peanut, pinenut, walnut and stones of apricot were extracted with petroleum benzene. The esterified lipids were analyzed for their fatty acid composition by gas chromatography (CC) whereas the extracted oils were tested for other physical characteristics like peroxide, iodine, anisidine and free fatty acid (FFA) values. The cc analysis showed that irradiation treatment of 1.5 kGy exhibited almost negligible effect on the composition of fatty acids. The peroxide, anisidine and FFA values were higher in the irradiated samples than untreated controls. It was also observed that these effects were increased by increasing the irradiation dose from 0.5 to 1.5 kGy but a reverse trend was noted in the case of iodine value in each case.

ABSTRAK

Beberapa jenis kacang telah disinari dengan sinar gamma pada takaran 0.5, 1.0 dan 1.5 kGy. Jumlah kandungan lemak dalam kacang seperti almon, kacang tanah, kacang pine, walnut dan biji aprikot yang tidak dan telah disinari telah diekstrak dengan menggunakan eter petroleum. Kandungan asid lemak pada lemak terester telah dianalisis dengan menggunakan kromatografi gas sedangkan minyak yang telah diekstrak telah diuji sifat­sifat fizikal seperti nilai peroksida, iodina, anisidina dan asid lemak bebas. Analisis kromatografi gas menunjukkan bahawa sinaran 1.5 kGy tidak memberi kesan yang bermakna terhadap kandungan asid-asid lemak. Nilai peroksida, anisidina dan asid lemak bebas adalah tinggi dalam kacang yang disinari. Telah juga diperhatikan bahawa kesan-kesan ini meningkat dengan peningkatan taka ran daripada 0.5 kepada 1.5 kGy tetapi kesan yang sebaliknya diperhatikan pada nilai iodina.

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