Abstract:
Olive (OO), sunflower (SO) and palm oil (PO) are three different types of highly demanded oils
available in Sri Lankan local market with multivariate functions. The present study aimed to
evaluate the quality parameters of randomly picked oil samples in Sri Lankan local market at the
time of purchasing. Ten brands (Three brands of OO, three brands of SO and four brands of PO)
of oil samples were purchased from local market. Specific gravity, viscosity, color, free fatty acid
(FFA) and peroxide value (PV) of all the oil samples were measured. PV and FFA of OOs were
ranged from 7.47 ± 0.95 meq/kg to 4.47 ± 0.23 meq/kg and 0.52 ± 0.11% to 0.38 ± 0.05%,
respectively. Thus, the recorded PV values are complying with the SLS standards and FFA values
are not in some brands (1591:2018) (maximum FFA as oleic acid: 0.3% and maximum PV: 10
meq/kg). Specific gravity and color of three brands of OO were significantly different (P˂0.05)
while viscosity was not (P˃0.05). PV and FFA values of SO were ranged from 14.80 ± 3.02
meq/kg to 7.67±0.70 meq/kg and 0.86 ± 0.30% to 0.53 ± 0.11%% respectively. The recorded PV
values of some brands in SO are comply with the SLS standards (946:2018) (maximum FFA as
oleic acid: 0.25% and maximum PV: 10 meq/kg) and PV values of other brands and all FFA
values are not. Specific gravity, viscosity and color of three brands of SO were significantly
different (P˂0.05). PV and FFA of PO were ranged from 0.36 ± 0.12 meq/kg to 0.25 ± 0.02
meq/kg and 11.13 ± 1.43% to 7.07 ± 0.69% respectively. Thus, the recorded PV and FFA of some
brands are comply with the SLS standards (720:2016) (maximum FFA as palmitic acid 0.25%
and maximum PV: 10 meq/kg). Within the three brands color and specific gravity of PO
significantly different (P˂0.05) and viscosity was not (P˃0.05). In conclusion, physicochemical
parameters of some brands in three different oil types are comply with the SLS standards and
also show significant differences within the brands.
