Application of Infrared Spectroscopy for Functional Compounds Evaluation in Olive Oil: A Current Snapshot

Abstract

Olive oil is a liquid fat obtained from the fruit of Olea europaea, a plant belonging to the Oleaceae family, which is widely cultivated and diffused in the Mediterranean area. It is largely produced and used since antiquity. It is mainly used and consumed as food but also as key ingredient in a wide variety of cosmetic products, e.g., to moisturize and nourish dry skin. In the last few decades, olive oil has received much attention as compared to the other seed-obtained oils as well as to the animal fats due to many functional compounds with positive effects on health. To maintain the genuine picture of olive oil, it is essential to assure its authenticity and quality. The presence of bioactive compounds, which characterize the olive oil owing to their antioxidant properties, can be assessed by spectroscopic and chromatographic methods. Currently, spectroscopic techniques combined with chemometric data analysis represent one of the most promising detection methods in the food sector. They offer rapid, versatile, and inexpensive data collection and analyses. The main advantages include the limited and simple sample preparation and the possibility to get spectra directly from the production line. Infrared spectroscopy (mid- and near-infrared) coupled to chemometrics is considered as powerful, fast, accurate, and nondestructive analytical tool for rapid and precise determination of the bioactive compounds content, as well of their bioactivities, i.e., antioxidant properties. These techniques represent a valid alternative to the existing conventional methods of analysis, e.g., based on chromatography and mass spectrometry. Indeed, the present review focuses on the application of infrared spectroscopy for functional compounds evaluation in olive oil.

Grape Seeds: Chromatographic Profile of Fatty Acids and Phenolic Compounds and Qualitative Analysis by FTIR-ATR Spectroscopy

“…The spectral band at 1744 cm −1 and the shoulder band at 1716 cm −1 is attributed to the absorption of the C=O bonds of the ester groups and it is related to the presence of the fatty acids and their glycerides, as well as pectins and lignins [60,61]. The bands around 1600 cm −1 are associated with the stretching of C=OO − and aromatic C=C groups, e.g., in pectins and phenolic compounds [61][62][63], but also with the bending vibrations of OH groups. The fingerprint region from 1500 to 800 cm −1 is very rich in peaks originating from various stretching, bending, rocking, scissoring, and torsional modes.…”

Olive Pulp and Exogenous Enzymes Feed Supplementation Effect on the Carcass and Offal in Broilers: A Preliminary Study

“…Olive pulp (OP) is the remainder of olive cake (raw material resulting from olive oil extraction) after the cake is dried. It is also one of the most interesting by-products of olive tree farming, being a good source of several biologically active compounds with antioxidant, antifungal, and antibacterial properties [1][2][3][4][5] with a great nutraceutical potential [6][7][8][9][10][11][12][13][14]. The use of by-products from different vegetal origins to supplement feed is, on the other hand, attracting growing interest due to environmentally friendly use, efficacy, and sustainability, other than avoiding the necessity to dump potentially useful and valuable by-products of the agro food system [15,16].…”

Processed Fruiting Bodies of Lentinus edodes as a Source of Biologically Active Polysaccharides

“…Fourier transform infrared spectroscopy enables us to detect functional groups which are present in a sample and is often used in the analysis of plant and fungi based polysaccharides [42][43][44]. FTIR coupled with a ATR accessory a is rapid and non-destructive tool which does not require sample preparation [45]. FTIR analysis may be useful in determination of polymers purity as well as for the detection of the type of glycosidic bond [46].…”