This experimental study (open access) developed the previously-reported use of ultrasound to differentiate types of vegetable oils. The researchers measured the attenuation and ultrasonic velocity of mixtures of organic argan oil (a premium North African product) with volumetric fractions of sesame oil, peanut oil or cheaper argan oil extracted from kernels depulped by goats.
They found that the measurements exhibit distinct behaviors manifested by electrical signals for the mixture obtained after the addition of each volumetric fraction, reflecting the capability of the adopted method to detect this difference. A notable decrease in ultrasonic velocity is observed in the mixtures as the quantity of added oil increases, with a maximum variation of 11 m/s for the argan/peanut oil mixture. Conversely, The attenuation of ultrasonic waves increases proportionally with the added volumetric fractions, with the argan/peanut oil mixture exhibiting an attenuation variation range of 3.57 Np/m.
They reported that prediction models for the added volumetric fractions to organic argan oil based on attenuation and ultrasonic velocity, showed a weak correlation between the predicted quantity of added oil and the actual quantity added to organic argan oil, with determination coefficients (r) not exceeding 65%. The weak correlation is due to the similar chemical compositions of the oils.
They conclude that ultrasonic-statistical analysis is a valuable tool for authenticating and ensuring the quality of vegetable oils. However, the limitations highlight the need to refine models for better accuracy. It offers a quick and simple alternative to traditional methods.
Comments