Abstract: In an effort to develop a new method for the rapid detection of camellia oil adulteration, pure camellia oil and adulterated camellia oil with soybean oil or corn oil were tested by proton nuclear magnetic resonance (1H NMR) spectroscopy, and then the obtained spectral data were analyzed by chemometric methods. The experimental results showed that pure and adulterated camellia oil could be clearly distinguished by principal component analysis (PCA). Moreover, the adulterated samples display regular distribution depending on the adulteration ratio. However, only a few samples at lower adulteration ratios were overlapped with pure camellia oil. The difference could be revealed by partial least squares discriminant analysis (PLS-DA) with 100% identification accuracy for pure camellia oil. Partial least squares (PLS) was further applied for the prediction of the adulteration level in camellia oil. The proposed method allowed accurate and fast detection of camellia oil adulteration, and showed a great application potential in quality control and evaluation of camellia oil.

Key words: camellia oil adulteration, proton nuclear magnetic resonance (1H NMR), principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), partial least squares (PLS)