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Analytical methods based on digital images coupled to chemometric tools are promising alternatives for developing analytical methodologies in determining quality parameters in foods. The total phenolics, monomeric anthocyanins, and tannin content were quantified based on digital images and pseudo-univariate calibration performed from Independent Components Analysis (ICA). Differences between ICA, Principal Component Analysis (PCA), and Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS), highlighting the chosen ICA for this proposal, were explained. In all pseudo-univariate calibration curves, correlation coefficients higher than 0.9 were achieved. The results suggest that digital images coupled with ICA can give applicable pseudo-univariate calibration models to determine bioactive compounds. Even more, the device to obtain an image is cheaper than most analytical instruments. Digital images may have a promising future in developing analytical methodologies for complex samples such as foods from a pseudo-univariate calibration perspective (where a small data set is needed in the calibration step).

The olive oil consumption has spread worldwide, increasing the necessity of quality assessment, and so forth, the search for new, alternative, and rapid data interpretation has started, boosting the interest and the use of data fusion that seek for an integration of results from different techniques or methodologies for the same data set. To better understand the storage effects on the Brazilian monovarietal extra virgin olive oil, data fusion was applied in the classical and alternative analysis, highlighting the similarities and differences between the techniques, assisting in the result interpretation. This perspective and strategy bring development to food chemistry analysis.

The use of chemometric tools is progressing to scientific areas where analytical chemistry is present, such as food science. In analytical food evaluation, oils represent an important field, allowing the exploration of the antioxidant effects of herbs and seeds. However, traditional methodologies have some drawbacks which must be overcome, such as being time-consuming, requiring sample preparation, the use of solvents/reagents, and the generation of toxic waste. The objective of this study is to evaluate the protective effect provided by plant-based substances (directly, or as extracts), including pumpkin seeds, poppy seeds, dehydrated goji berry, and Proven&ccedil, al herbs, against the oxidation of antioxidant-free soybean oil. Synthetic antioxidants tert-butylhydroquinone and butylated hydroxytoluene were also considered. The evaluation was made through thermal degradation of soybean oil at different temperatures, and near-infrared spectroscopy was employed in an n-way mode, coupled with Parallel Factor Analysis (PARAFAC) to extract nontrivial information. The results for PARAFAC indicated that factor 1 shows oxidation product information, while factor 2 presents results regarding the antioxidant effect. The plant-based extract was more effective in improving the frying stability of soybean oil. It was also possible to observe that while the oxidation product concentration increased, the antioxidant concentration decreased as the temperature increased. The proposed method is shown to be a simple and fast way to obtain information on the protective effects of antioxidant additives in edible oils, and has an encouraging potential for use in other applications.

Gluten-free biscuits were developed with the addition of chia seeds (Salvia hispanica L.) and turmeric powder. An experimental design 2(2) were employed in the formulation optimization that promotes better sensory acceptance through acceptance test with a hedonic scale of 9 points. For characterization purposes, the centesimal composition from chia seeds and the turmeric powder were determined. The biscuits were produced from an optimized formulation with and without chia seeds and turmeric powder with microbiological results safe for consumption by evaluation Salmonella sp., positive coagulase Staphylococcus, and Coliforms to 45 °C. The Principal Components Analysis (PCA) was used in the investigation of sensory results (color, flavor, texture, smell, appearance, overall impression). It was also considered the habits of consuming food with/without gluten, purchase intentions, including age and gender. The results show that there is no distinction between the biscuits with the addition of chia seeds and turmeric powder. A statistical test using the confidence ellipse confirms that there no significant difference, at a 95% confidence level, among the sensory results for the biscuits with and without chia seeds and turmeric powder.

Samples of chia seeds (Salvia hispanica L.) were degreased by cold pressing and the residue obtained named degreased chia seeds (DCS) had the antioxidants extract obtained. A 22 experimental design was employed in order to evaluate the factors ethanol concentration and extraction time. The optimized conditions were extraction time 15 min with ethanol 70% where the activity (RSA), evaluated by the DPPH (2,2-diphenyl-1-picryl-hydrazyl) method was 94.76%. For this extract, the total phenolics content was 359.64 mg EGA/100 g. A pseudo-univariate calibration model is proposed as an alternative methodology to determine the %RSA by using the relative concentration from multivariate curve resolution with alternating least squares (MCR-ALS) from near-infrared (NIR) spectra of the antioxidant extract from DCS. The results suggest the possibility of %RSA determination directly from NIR spectra from extracts from DCS by using the multivariate resolution method MCR-ALS.

The extra virgin olive oil (EVOO) has a certain oxidation resistance when compared to other vegetable oils without refining process, due to their large composition of monounsaturated fatty acids, antioxidants, and bio-compounds. The main of this research was to evaluate and monitor the behavior of autoxidative processes through the storage time in two packaging systems of different EVOO monovarietals produced in Minas Gerais, Brazil by using ultraviolet and visible spectroscopy (UV–Vis) with multivariate curve resolution with alternating least squares (MCR–ALS). We analyzed six EVOOs produced from different monovarietals (Arbequina, Empeltre, Coratina, Grappolo, Koroneiki, and Maria da Fe), over the course of 1 year, performed the analysis in times 0, 30, 90, 180, and 365 days, and storage in glass bottles and tinplate cans. The UV–Vis spectroscopy coupled with MCR–ALS was a feasible tool to monitor autoxidation processes in EVOO through storage time and in the monitoring of the EVOO quality in different package systems. The glass bottles were a package system that provides more protection for the autoxidation processes with the time for the EVOO from monovarietals Empeltre, Arbequina, and Coratina. In addition, it was possible to make a differentiation between the monovarietal olive oils produced in Brazil by observing the amount of phenolic compounds present in the chemical composition of each oil. Allowing gather information about the formation of oxidative products may correlate with the shelf life of the EVOO.