Quality assessment of palm products upon prolonged heat treatment.
Extending the frying-life of oils is of commercial and economic importance. Due to this fact, assessment on the thermal stability of frying oils could provide considerable savings to the food processors. In this study, the physico-chemical properties of five palm products mainly palm oil, single-fractionated palm olein, double-fractionated palm olein, red palm olein and palm-based shortening during 80 hours of heating at 180 degrees C were investigated. Heating properties of these products were then compared with that of high oleic sunflower oil, which was used as reference oil. The indices applied in evaluating the quality changes of oils were free fatty acid, smoke point, p-anisidine value, tocols, polar and polymer compounds. Three palm products i.e. palm oil, single-fractionated palm olein and double-fractionated palm olein were identified to be the most stable in terms of lower formation of free fatty acid, polar and polymer compounds as well as preserving higher smoke point and tocols content compared to the other three oils. The low intensity of hydrolytic and oxidative changes due to prolonged heating, suggests that these palm products are inherently suitable for frying purposes.
Tarmizi
Azmil Haizam Ahmad
AH
Analytical and Quality Development Unit, Malaysian Palm Oil Board, Persiaran Institusi, Selangor, Malaysia. azmil_haizam@mpob.gov.my
Lin
Siew Wai
SW
D000814:Aniline Compounds / Q000032:analysis; D005223:Fats / Q000737:chemistry*; D005230:Fatty Acids, Nonesterified / Q000032:analysis; D005524:Food Technology / Q000379:methods*; D006358:Hot Temperature; D000073878:Palm Oil; D010938:Plant Oils / Q000737:chemistry* / Q000592:standards*; D011786:Quality Control; D012015:Reference Standards; D000074242:Sunflower Oil; D013997:Time Factors; D024505:Tocopherols / Q000032:analysis
D000814:Aniline Compounds; D005223:Fats; D005230:Fatty Acids, Nonesterified; D010938:Plant Oils; D000074242:Sunflower Oil; C013813:4-anisidine; D000073878:Palm Oil; D024505:Tocopherols