Detection of inverted beet sugar adulteration of honey by FTIR spectroscopy

Abstract

A combination of Fourier transform infrared (FTIR) spectroscopy and multivariate statistics as a screening tool for the determination of beet medium invert sugar adulteration in three different varieties of honey is discussed. Honey samples with different concentrations of beet invert sugar were scanned using the attenuated total re¯ectance (ATR) accessory of the Bio-Rad FTS-6000 Fourier transform spectrometer. The spectral wavenumber region between 950 and 1500 cm À1 was selected for partial least squares (PLS) regression to develop calibration models for beet invert sugar determination in honey samples. Results from the PLS (®rst derivative) models were slightly better than those obtained with other calibration models. Predictive models were also developed to classify beet sugar invert in three different varieties of honey samples using discriminant analysis. Spectral data were compressed using the principal component method, and linear discriminant and canonical variate analyses were used to detect the level of beet invert sugar in honey samples. The best predictive model for adulterated honey samples was achieved with canonical variate analysis, which successfully classi®ed 88±94 per cent of the validation set. The present study demonstrated that Fourier transform infrared spectroscopy could be used for rapid detection of beet invert sugar adulteration in different varieties of honey.

Quantitative analysis of physical and chemical measurands in honey by mid-infrared spectrometry

“…Recent publications [10][11][12][13][14] claim that honey adulteration with medium invert cane, beet and corn syrup as well as pure glucose, fructose, and sucrose can be detected by infrared spectroscopy using a multiple reflection ATRsampling accessory and chemometric models. However, the natural variation of the honey composition was not considered, as only three samples of different botanical origin were studied.…”

“…In some of the experiments carried out by using artificially adulterated sugar solutions [10,11,13], the concentration of sucrose was so high that the adulteration could have been easily determined by analysing the sucrose content as it exceeded the limits defined by the European Honey Directive and the Codex Alimentarius [1,2]). In addition, the experimental design facilitated the detection of such an adulteration because the water content was also changed when the honey samples were adulterated with the solutions of pure sugars [13,14]. To prevent this problem Kelly et al [15] proposed to dilute all samples with water and to adjust the solid content to 70…”

Analysis of adulteration in honey with standard sugar solutions and syrups using attenuated total reflectance-Fourier transform infrared spectroscopy and multivariate methods

“…Factors are the result of a transformation of a data matrix where the goal is to reduce the dimensionality of the data set (Edelmann, Diewock, Schuster, & Lendl, 2001). In this adulteration analysis, the predicted values were correlated with the actual values, and the accuracy of prediction was assessed by the SEP. Cross validation procedure was used in all cases to minimize the risk of overfitting when calibration accuracy was evaluated (Sivakesava & Irudayaraj, 2001b).…”

“…Given its composition (mainly carbohydrates and water), honey is adulterated in the practice by cheaper, commercially available sugar syrups with similar composition. In several feasibility studies, the ability of near infrared spectroscopy (NIR) and middle infrared spectroscopy (MIR) to detect adulteration of authentic honey by either added corn syrup (CS) (Sivakesava & Irudayaraj, 2001a), beet invert syrup (BI) (Sivakesava & Irudayaraj, 2001b), sucrose syrup (SS) (Garcı´a, 2003) or high fructose corn syrup (HFCS) (Gallardo, Osorio, Zun˜iga, & Rivera, 2009) has been reported.…”

Pulicação de métodos de análise multivariada no controle qualitativo de essências alimentícias empregando espectroscopia no infravermelho médio

“…Com a popularização das ferramentas de análise multivariada, a técnica de espectroscopia no infravermelho médio vem sendo cada vez mais empregada para a análise qualitativa e quantitativa de alimentos [6,11,20,21]. A intensificação dessas aplicações na área de alimentos ocorreu no início da última década sendo marcada por Wilson [29], que, em 1990, apresentou as potencialidades da espectroscopia por reflexão no infravermelho médio: reflexão total atenuada (ATR), detecção fotoacústica e reflexão difusa (DRIFTS), para análise de alimentos e sua utilização no controle industrial.…”