DSC coupled with PCA as a tool for butter authenticity assessment

Abstract

The authenticity assessment of butter is still a big challenge for analytics. Due to its low cost, palm oil (PO) is the edible fat most frequently used as an adulterant in the production of butter. The aim of this study was to test the feasibility of the DSC technique coupled with principal component analysis (PCA) for the distinction of pure butterfat from adulterated. A differential scanning calorimeter DSC 7 from Perkin-Elmer was used for the examination of crystallization and melting properties of pure butterfat and its mixtures with PO (2,5,10,15, 20, 25, 30, 35 % w/w). The addition of PO affects the thermodynamic parameters of the crystallization and melting of butter, which modifies the position and area of phase transition peaks. A large dataset concerning DSC cooling and heating parameters such as temperatures, enthalpies and peak heights was obtained. Processing of data was supported by the PCA method, which proved its applicability for differentiation between genuine and adulterated fat. Statistical analysis revealed that the best separation of samples with different palm oil concentration was achieved using DSC melting parameters of enthalpies and peak heights of low and medium melting fractions. PCA of crystallization parameters did not give such distinct separation. The results of this study confirmed that the DSC technique coupled with PCA can be successfully applied to detect with high sensitivity (from 2 %) the adulterant in butter.

Authenticity Assessment from Sesame Seeds to Oil and Sesame Products of Various Origin by Differential Scanning Calorimetry

“…The relation among thermodynamic parameters (% Peak1, ∆Hm Peak1, ∆Hm Peak2, ∆Hm total, and T 1/2 ), as well as scatter plots of sesame products (H, HC, HP, TH), authentic (S) and adulterated (SPO) sesame oils are depicted in Figure 4 a,b respectively. Similar study about the implementation of PCA as an authenticity assessment was reported by Tomaszewska-Gras [ 28 ]. Figure 4 a visualizes the relations between two first principal components (PC1 and PC2), which described 92.38% of the initial variability.…”

Comprehensive Thermal Characteristics of Different Cultivars of Flaxseed Oil (Linum usittatissimum L.)

“…In order to establish the relations between thermo-oxidative stability and stability determined by chemical methods, principal component analysis was performed. This is a method for detecting structure in the relationships between variables and to classify the objects [ 29 ]. Principal component analysis (PCA) was used to describe the oxidative stability of flaxseed oil measured by different methods.…”

Differential scanning calorimetry for authentication of edible fats and oils - What can we learn from the past to face the current challenges?

“…Another alternative approach to assessing butter authenticity was presented in the paper by Tomaszewska-Gras, in which the suitability of the chemometric method i.e. principal component analysis (PCA) for distinguishing genuine from adulterated butterfat was tested [ 104 ]. DSC parameters such as temperature, enthalpy, peak height and partial surface area were selected for the best differentiation of butterfat samples with various levels of palm oil added as an adulterant.…”