Quick Fluorescence Method for the Distinguishing of Vegetable Oils

Abstract

This paper presents the possibilities offered by fluorescence spectroscopy for the identification of vegetable oils such as soybean, sunflower, flax, walnut, corn, almond, sesame, olive and pumpkin oils. The probes under study have been excited with two types of sources: a laser diode (LD) and light-emitting diodes (LEDs) emitting in the UV and in the visible range. Total luminescence spectra were recorded by measuring the emission spectra in the range 350-720 nm at excitation wavelengths from 375 to 450 nm. The excitation-emission matrices have been obtained and two basic fluorescence regions in the visible have been outlined. On this basis the fluorescence spectra of the oils have been subdivided into three categories depending on the prevalence of the fluorescence maxima. The samples show differences in their fluorescence spectra. The latter fact shows that fluorescence spectroscopy can be used for the quick identification of edible oils. The fatty acid, the tocopherol, the beta-carotene and chlorophyll contents in the analyzed oils have been studied. It is shown that some of the types of oils differ significantly from each other by the first derivatives of their fluorescence spectra. There also exist color differences between the groups of vegetable oils under study.

Investigating temperature effects on extra virgin olive oil using fluorescence spectroscopy

“…Before going into the details of the effects of temperature on EVOO, a short description of its florescence emission spectra is given in this paragraph with the help of existing literature [5,15,17,24,[35][36]39]. A shaded average fluorescence spectrum of non-heated EVOO is displayed in figure 1(b) when it is excited with a wavelength of 350 nm.…”

“…The band centered at 515 nm is actually composed of two closely spaced bands, which can be seen carefully as 515 and 525 nm. The emission bands at 380, 440, 470 and 525 nm originate from compounds of vitamin E, particularly from α-tocopherol [5,17,35,39] and the band at 525 nm is also responsible for the presence of β-carotenoids (vitamin A) [5,36]. The emission band at 515 nm is assigned to vitamin A [40].…”

Monitoring the Quality Parameters of Mango Juices Using Fluorescence Spectroscopy

“…According to [20], beta-carotene produces uorescence maxima about 520-560 nm. The orange hue of mangoes is attributed to beta carotenoids, which are responsible for the 525 and 550 nm peak.…”

Detection of long storage and sunflower adulteration of olive oils using ultra-violet (UV) spectroscopy method

“…To determine the type of adulterant, chemical methods such as gas chromatography or high performance liquid chromatography are used (Inthiram, Mirhosseini, Tan, Mohamad, & Lai, 2015). Ultraviolet (UV) spectroscopy can provide information on the degree of oxidation of the olive oil (Nikolova, Eftimov, Perifanova, & Brabant, 2012). More specifically, the quality of olive oil is Copyright ©2019 ISEKI-Food Association (IFA) 10.…”