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Abstract: A Fourier transform infrared spectroscopy–Partial Least Squares (FTIR–PLS) strategy for the determination of the quality of olive fruits and the respective virgin olive oil (VOO) has been developed. This methodology has been demonstrated as able to correlate the level of fly attack in olive oils with their FTIR spectra. A multivariate calibration model was built by the PLS algorithm using the 4000–700 cm−1 spectral range on pretreated data and an evaluation of some of the usual quality parameters of VOO (free acidity, fatty acids composition, oxidative stability by OSI time and phenolic compounds obtained by capillary electrophoresis) and was performed to corroborate the real influence of fly attack on the quality of the oils. Furthermore, the evaluation of the FTIR data showed some differences in the regions of the fatty acids and phenolic compounds depending on the percentage of fly attack on the olives. This non-destructive method easily allows a non-destructive measure and, at the same time, establishes the level of Bactrocera oleae attack in olive fruit thus analysing directly the olive oil obtained without any previous treatment. [Copyright &y& Elsevier]

Abstract: The aim of this paper was to use the air classification technology to produce barley flours enriched in phenolic compounds and to obtain naturally enriched ingredients for pasta and bakery industry. Phenolic compounds in barley have been described in literature using different methodologies that are not easily comparable. This paper describes a comparative study between different separative and spectrophotometric methods to determine free and bound phenolic compounds in barley flours and their air classified fractions from three different cultivars grown in the same experimental field. To this end, reversed phase-high performance liquid chromatography, micellar electrokinetic chromatography, and spectrophotometric determinations were applied. The barley phenolic compounds analyzed included mainly catechins and proanthocyanidins as free phenols, and hydroxycinnamic acids and their derivatives as bound phenols. The enriched fractions obtained by air classification showed an increase of free flavan-3-ols of 157–173% compared to whole flour. The same fractions also reported larger concentration of bound phenolic compounds (160–236%) with respect to whole flours. Air classification results a good technique to enrich the flours and to utilize the barley co-products. [Copyright &y& Elsevier]

This study focused on evaluating the mitigating effect of five different natural extracts of commercial tannins on the concentration of food contaminants such as acrylamide (AA), glycidols (GD), and monochloropropanediols (MCPDs) in potato chips and frying oils after the impregnation of potatoes with tannins. The impregnated samples were used to perform 4 consecutive fryings to simulate the effect produced in restaurants. AA mitigation was achieved in all pre-treated chips throughout the four frying cycles (except for the chestnut extract). The highest AA mitigation (86.6%) was achieved using quebracho extract. This correlated positively with the progress of Maillard reaction measured at 284 nm. In potato chips, 3-MCPD and GD were decreased by most tannins tested, whereas 2-MCPD was only mitigated using hydrolyzable tannins. However, in frying oils, 3-MCPD showed a decrease using chestnut, grape seed and quebracho extracts, 2-MCPD decreased using all tannins, and no effect was observed on GD. To our knowledge, this is the first study using tannins as a mitigation strategy to decrease MCPDs and GD; and it seems a good approach to keep low concentrations of these compounds. Indeed, hydrolyzable tannins seem the best option to mitigate MCPD and GD and condensed tannins the best one to mitigate AA. • Impregnation of potatoes has been done with five natural extracts of tannins. • AA, MCPD and GD mitigation has been achieved in fried potatoes and frying oil. • Hydrolyzable tannins are the best tannins to mitigate MCPD and GD. • Condensed tannins are the best option to mitigate AA. [ABSTRACT FROM AUTHOR]

• Addition of polyphenols can mitigate the acrylamide formation in fried potato model. • The added polyphenols are obtained from the olive oil supply chain. • Hydrophobicity and activity of the polyphenols seem to be correlated. • TyAc and HTyAc presented the highest mitigation effects on AA content. • TyAc added to the dough showed around 90 % AA reduction. In order to find innovative protocols to reduce acrylamide (AA), a genotoxin and a probable carcinogen, in foods, several phenolic compounds were considered as additives to a potato derivative. Phenols are obtained from the by-products of the olive production chain. Potato flakes were kneaded with water containing different concentrations of a single phenol: tyrosol (Ty), hydroxytyrosol (HTy), tyrosyl acetate (TyAc), hydroxytyrosyl acetate (HTyAc), caffeic acid and oleuropein. After a cooking step at 175 °C for 4 min, AA was extracted, derivatized with xanthydrol and quantified by GC–MS. The results obtained for Ty, HTy, caffeic acid and oleuropein showed AA reduction ranging from 29 % to 47 %, whereas with TyAc and HTyAc the mitigation effect was noticeably stronger (90 and 75 %). The less polar molecule, TyAc, showed the best inhibition performance. These preliminary results show that phenolic compounds from olive by-products could also be valorized as food starchy additives. [ABSTRACT FROM AUTHOR]