Acrylamide–Fat Correlation in Californian-Style Black Olives Using Near-Infrared Spectroscopy

Abstract

Californian-style is one of the most important black table olive elaborations. During its processing, table olives produce acrylamide, a potential carcinogen compound generated during sterilization. In the present study, total fat and acrylamide content in Californian-style table olives were determined and a regression between them was performed (acrylamide concentration range: below limit of detection—2500 ng g−1 and 8–22% for total fat). Nowadays, there are fast and efficient new techniques, such as Near-Infrared Spectroscopy (NIRS) to measure fat content parameters. In that sense, NIRS was used to perform a fat content quantification model in olives in order to indirectly determine acrylamide content. Calibration models for fat quantification were obtained in defatted olive pastes from a unique variety and for olive pastes from different varieties. In the first case, best results were obtained since only one variety was used (R2 = 0.9694; RMSECV = 1.31%; and REP = 8.4%). However, in the second case, results were still acceptable R2 = 0.678, RMSECV = 2.3%, REP = 17.7% and RMSEV = 2.17%. Regression coefficients showed the most influence variables corresponded with fat. The determination coefficient for the fat and acrylamide correlation was high (r = 0.877), being an efficient approach to find out the contribution of fat degradation to acrylamide synthesis in table olives.

Identification of the Beverage Sotol Adulterated with Ethylene Glycol Using UV-Vis Spectroscopy and Artificial Neural Networks

“…The main advantage of this analytic technique is its high sensitivity and resolution, which depend on the type of detector incorporated into the gas chromatograph equipment, allowing in some cases the identification of substances with concentrations as low as 1 × 10 −12 g. However, there are also other non-destructive techniques that could be considered for the same purpose [11]. These techniques include (a) infrared spectroscopy (analysis of the interaction of infrared light with molecules) [12], (b) Raman spectroscopy (analysis of the inelastic scattering of photons by matter after laser excitation) [13], (c) fluorescence spectroscopy (analysis of the light emissions which take place after the excitation of the electrons in a material) [14], (d) an electronic tongue (this is a multisensor system based on various sensor arrays with limited selectivity and allowing for advanced mathematical data analysis) [15], (e) nuclear magnetic resonance spectroscopy (analysis of the molecular structure of a material by observing and measuring the interaction of nuclear spins when placed in a powerful magnetic field) [16], (f) an electronic nose (captures the fingerprints of volatile organic compounds present in an alcoholic beverage sample using an array of semi-selective sensors) [17], (g) a colorimetric sensor array (produces a chemical interaction between the active center and analyte, which results in chemo-responsive changes in color) [18], (h) a combination of sensors (involves a data fusion approach with various sensors to acquire an optimal response) [19] and UV-Vis spectroscopy [20], which is the selected analytical technique carried out in the present work.…”