Raman Spectroscopic Barcode Use for Differentiation of Vegetable Oils and Determination of Their Major Fatty Acid Composition

Abstract

In this study, differentiation of vegetable oils and determination of their major fatty acid (FA) composition were performed using Raman spectral barcoding approach. Samples from seven different sources (sunflower, corn, olive, canola, mustard, soybean and palm) were analyzed using Raman spectroscopy. Second derivative of the spectral data was utilized to generate unique barcodes of oils. Chemometric analyses, namely, principal component analysis (PCA) and partial least square (PLS) methods were used for data analysis. PCA was applied for classification of the samples according to the differences in their levels arising from their barcode data. A successful differentiation based on second derivative barcodes of Raman spectra (2D‐BRS) of vegetable oils was obtained. In addition, PLS method was applied on 2D‐BRS in order to determine the major FA composition of these samples. Coefficient of determination values for palmitic, stearic, oleic, linoleic, α‐linolenic, cis‐11 eicosenoic, erucic and nervonic acids were in the range of 0.970–0.989. Limit of detection and limit of quantification values were found to be satisfactory (0.09–8.09 and 0.30–26.95 % in oil) for these fatty acids . Advantages of both chemometric analysis and spectral barcoding approach have been utilized in the present study. Taking the second derivative of the Raman spectra has minimized background variability and sensitivity to intensity fluctuations. Spectral conversion to the barcodes has further increased the quality of information obtained from Raman spectra and also made it possible to improve the visualization of the data. Converting Raman spectra of oils into barcodes enables simpler presentation of the valuable information, and still allows further analysis such as classification of vegetable oils and prediction of their major fatty acids with high accuracy.

Analysis of Pork Adulteration In Recycled Frying Oils Using Raman Spectroscopy

“…The other nine minor peaks such as 845 cm -1 , 870 cm -1 , 890 cm -1 , 970 cm -1 , 1065 cm -1 , 1083 cm -1 , 1122 cm -1 , 1270 cm -1 and 1745cm -1 could also observe through the Raman spectra. Velioglu et al had found seven significant Raman bands in palm oil and other vegetable oils such as soybean, sunflower, corn, mustard, canola and olive which consist of 869 cm -1 , 971 cm -1 , 1085 cm -1 , 1265 cm -1 , 1303 cm -1 , 1441 cm -1 and 1656 cm -1 [18]. This shows that the resulted peaks of palm frying oil in this study might indicate the significant Raman spectra characteristics of vegetable oils.…”

Rapid Authentication of Potato Chip Oil by Vibrational Spectroscopy Combined with Pattern Recognition Analysis

“…Similar to our research using the Raman approach, Yang et al [ 50 ] used linear discriminant analysis (LDA) and canonical variate analysis (CVA) to discriminate corn oil, peanut oil, canola oil, safflower oil, etc., resulting in about 94% classification accuracy with their FT-Raman equipment. In addition, Velioglu et al [ 52 ] differentiated seven vegetable oils successfully using principal component analysis (PCA) by Raman spectroscopic barcode. Similar to our NIR approach, Yang et al [ 50 ] differentiated oils using LDA and CVA with 93% accuracy with their FT-NIR equipment, and Bewig et al [ 53 ] discriminated vegetable oils successfully by NIR reflectance spectroscopy.…”

Inclusion complex of peony (Paeonia suffruticosa Andr.) seed oil with β‐cyclodextrin: preparation, characterisation and bioavailability enhancement

“…Peony (Paeoniaceae, genus Paeonia) is a traditional plant in China, which not only possesses unique floral characteristics but also contain active ingredients, such as essential oils, flavonoids and phenolic compounds, all widely studied. Moreover, peony seeds contain high amounts of oils (about 35%), the GC‐MS analysis indicated that more than 85% of PSO comprises unsaturated fatty acids (UFAs), such as linolenic acid C18:3, linoleic acid C18:2 and oleic acid C18:1 (Li et al ., ), which is higher than other seed oils (such as peanut, camellia, palm, olive, corn, sunflower oils; <10%) (Velioglu et al ., ). Linolenic acid exhibits antioxidant function, reduces blood fat and cholesterol levels and prevents diseases of heart, head and blood vessels; however, linolenic acid cannot be synthesised by the body itself.…”