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This study analyses various chicken cuts (breast, leg, and thigh) in terms of ten biocompounds: nicotinamide, anserine, carnosine, malondialdehyde, and biogenic amines (putrescine, cadaverine, histamine, tyramine, spermidine, and spermine). The analysis is conducted on refrigerated chicken meat cuts using three different packaging solutions: modified atmosphere packaging (MAP), vacuum skin packaging (SKIN), and permeable O 2 plastic film (STRETCH). Our results show that nicotinamide was the most discriminant compound followed for cuts and time. Remarkably, its concentration decreases over time, unaffected by any of the packaging solutions. The collective contribution of all the examined biocompounds is highlighted through multivariate statistical analysis, utilizing partial least square discriminant analysis (PLS-DA) and the support vector machine (SVM) algorithm. Both machine learning models demonstrate high classification accuracy: for cut, storage time, and packaging, PLS-DA yields classification accuracy rates of 87%, 85%, and 70%, respectively. SVM achieves even higher accuracy rates of 97%, 99%, and 94% for cut, storage time, and packaging, respectively. These results underscore the importance of considering the combined influence of all the biocompounds investigated in this study for a finer classification of chicken meat cuts and packaging. Furthermore, our findings highlight the efficacy of SVM as a discriminant multivariate approach in food classification. • Nicotinamide, anserine, carnosine, and Biogenic amines, as new markers of quality in chicken meat. • Nicotinamide is the most discriminative compounds among cuts and storage time. • Packaging solutions employed, limitedly influenced bio compounds evolution. • Machine learning models, mainly SVM allowed a good classification. [ABSTRACT FROM AUTHOR]

Abstract: A durum wheat was milled in order to obtain medium (M), medium coarse (MC) and coarse (C) semolinas with an average particle size of 275, 375 and 475μm respectively. The three semolinas were characterized for their chemical and physical properties. The M semolina showed higher ash, protein and gluten content, a higher gluten extensibility but a lower gluten index and yellow colour than coarser semolinas. Spaghetti were produced with the three semolinas. Dried spaghetti were characterized for their diameter, hardness and colour and eventually tested for their cooking quality. Spaghetti from MC and C semolina showed higher optimum cooking time (OCT) than spaghetti from M semolina. Cooking time being equal, the weight and diameter increase was higher in spaghetti from coarser semolinas. Within OCT, the hardness of spaghetti from MC and C semolina was higher than that of spaghetti from M semolina. The high OCT and hardness (before OCT) of the semi-cooked pasta obtained from MC and C semolina could be useful in two-step cooking processes in which pasta is pre-cooked and cooled before the final cooking step. [Copyright &y& Elsevier]

Abstract: The surface and interfacial properties of gallic acid, catechin and quercetin, and their effect on the dispersion degree and the oxidative stability of olive oil oil-in-water (O/W) emulsions prepared using β-lactoglobulin and Tween 20 were studied. Gallic acid showed no effect on the surface properties while catechin was proven to be able to accumulate at the air/water interface, decreasing the surface tension values with increasing its concentration. All the phenolic antioxidants caused a decrease in the interfacial tension at the oil/water interface, even though only catechin and quercetin showed a concentration dependent behaviour. In emulsions, gallic acid did not affect the droplet size of the systems, catechin caused the formation of oil droplets bigger than those of the control, whilst quercetin improved the dispersion state of the emulsions with the increasing of its concentration. Gallic acid, despite its partitioning in the water phase due to its polarity, delayed the formation of both the hydroperoxides and TBARs and limited their accumulation. Catechin did not affect the formation of oxidation products whilst quercetin, among the tested antioxidants, caused the lowest formation of both hydroperoxides and TBARs through 33 days of storage. [Copyright &y& Elsevier]

• The SPME/GC–MS analysis of wheat organic volatiles was implemented. • 158 VOCs, of which 98 never found before in wheat kernels, were identified. • Pedoclimatic conditions were the highest source of variability in VOCs profile. • Selected VOCs permitted to discriminate among wheats cultivated in different areas. • Selected VOCs permitted to discriminate between durum and common wheat. Food volatile organic compounds (VOCs) analysis is a useful tool in authentication and classification processes, but, to date, the analysis of wheat VOCs is still little explored. In this study a method of analysis based on solid phase microextraction coupled with gas chromatography-mass spectrometry was optimized by testing different types of fibers, sample preparation methods and amounts, extraction temperatures and times, desorption times and oven programs. The analysis was applied to six wheat cultivars harvested in different areas, and permitted to identify 158 VOCs, of which 98 never found before. A principal component analysis performed on the dataset showed that the area of cultivation accounted for the highest source of variability. Partial least squares analysis permitted to correctly classify wheats based on their cultivation area and species, and to identify the most discriminant VOCs. These results are promising for the study of the influence of geographical origin on wheat quality. [ABSTRACT FROM AUTHOR]

The effect of oleuropein on the gelation properties of whole egg yolk at different pHs (2, 4.5 and 6.4) was studied. Egg yolk solutions were added with increasing amount of pure oleuropein, gelled by either thermal (pHs 4.5 and 6) or acid gelation (pH 2) and submitted to frequency sweep and stress relaxation tests. The experimental data obtained by the frequency sweep tests were modeled with a power law equation in order to get the coordination number z and the proportional coefficient A, which describe the network extension and its strength, while data obtained from stress-relaxation tests were fitted by a generalized Maxwell model with 5 elements. The addition of oleuropein affected the gelation behavior as well as the rheological properties of the gel network, and the effect was influenced by the pH of the systems. A shift of the gel point towards lower temperatures was observed in the presence of the phenolic compound, and this effect was significant in the systems at pH 4.5 (from 72.55 ± 0.07 °C to 70.43 ± 0.06 °C). According to the results obtained from the modelling of the frequency sweep test, gels at pH 6.4 and 2 were characterized by a weak network; on the contrary, at pH 4.5 the network was characterized by a low number of flow units (lower z, z = 16.52 on average) interacting with one another in a more strictly way (higher A, A = 5362 Pa s 1/z on average). Such findings were successively confirmed by the stress relaxation results where it was shown that firmer gels were obtained at pH 4.5 after oleuropein enrichment. [ABSTRACT FROM AUTHOR]

Salt (NaCl) penetration was studied on dry-cured hams of different weight processed by two different salting processes. Chemical composition and water activity (a w ) were analysed on two of the most representative ham muscles during the process. The normalized Weibull cumulative distribution was used to fit salt uptake in Biceps femoris m. (BF) and to calculate the salt diffusion coefficient. The a w values strictly depend on the Salt Index (S.I., g NaCl 100 g w −1 ). The S.I. of BF samples from hams taken at different processing steps, were modelled as a function of a w by both a linear and a first order polynomial model achieving good fitting (R 2 = 0.92). The calibration root mean square error (RMSE) resulted being of 1% for both models. Cross validation was performed and the RMSEs were of 0.62% and 0.61% for the linear and polynomial models, respectively. These models can be useful to manage the salting process in dry-cured hams at industrial level. [ABSTRACT FROM AUTHOR]

• Heritage wheat varieties showed a VOCs pattern distinct from modern varieties. • Discriminant analyses classify heritage wheat by a set of odor types. • Solina wheat was characterized by floral and herbal odors. • Cappelli wheat was characterized by waxy and aldehydic odors. • Differences in VOC profiles are related to the chronological distance among wheat. Nowadays, the interest in ancient wheat is increasing and this trend point towards the local production of crops and is connected to sustainability. In this study, two ancient wheat (Solina and Cappelli) and four modern (common and durum) varieties were cultivated in experimental fields sited at three different altitudes for three consecutive years in the Abruzzo region. The six wheat varieties were analysed by solid phase microextraction coupled with gas chromatography-mass spectrometry and a chemometric approach. 149 compounds, most of which are odor active, were identified in 109 wheat samples. Heritage wheat varieties showed a volatile organic compounds (VOCs) profile different from modern varieties along with a characteristic set of odor types. An 82% of correct classification was achieved for heritage wheat varieties. VOCs with floral and herbal odors were the most important odor scents for Solina classification, whereas waxy odor was the most important for Cappelli discrimination. [ABSTRACT FROM AUTHOR]

The application of vacuum impregnation (VI) for the production of high quality fresh like apple products has been investigated. Preliminary tests were carried out to select the optimal VI treatment conditions (P: 857–50 mbar; VI time: 10–1000 s). The use of isotonic sorbitol, glucose, fructose, sucrose, trehalose and maltose solutions was then studied to keep quality and improve stability of the VI treated apples. VI at 738 mbar for 10 s allowed the penetration of the impregnation agent (water) with minimal effects on fruit composition and quality. VI isotonic solutions determined a limited solute increase while affected mechanical properties positively; firmness of apples processed with sorbitol solution was higher than that of the fresh fruit. Moreover, they contributed to preserve apples from browning. After 7 days, h° values significantly higher than the untreated samples were obtained with trehalose > sorbitol > glucose > sucrose > maltose. Sensory analysis confirmed the positive effect of isotonic VI solution on apples quality. [ABSTRACT FROM AUTHOR]

Non enzymatic browning (NEB) kinetics were studied at 125, 135 and 145 °C during a cocoa beans roasting process aimed to reach a final moisture content of 2 g 100 g −1 . Colour lightness and hue angle decreased with roasting time following a first and a zero order kinetic, respectively. Moisture content being equal, high temperature-short time (HTST) roasting processes minimized the extent of browning reaction. Melanoidins increased with roasting time following an asymptotic kinetic. Moisture content being equal, HTST processes maximized the melanoidins formation. The energy of activation of melanoidin formation (132 kJ mol −1 ) was higher than those of colour changes and polyphenol oxidation (between 60 and 80 kJ mol −1 ), thus NEB during roasting is not solely dependent on Maillard reaction occurrence. Hydroxymethylfurfural (HMF) increased exponentially with roasting time but its final content was low (0.1–0.8 g kg −1 ). HTST processes minimized the HMF formation, which was not temperature dependent and was influenced by concentration. [ABSTRACT FROM AUTHOR]

Plants of lettuce were subjected to four abiotic limiting growing conditions, i.e. no phosphorus fertilization (0_P), no nitrogen fertilization (0_N), limitation of the photosynthetic active radiation (PAR, range from 400 to 700 nm) (LR) and water availability constraint (WR). Yield, yield components, root growth, bound and soluble phenolic compounds accumulation and their antiradical activity were investigated. Leaf length decreased by 21% in 0_N while increased by 57% in LR with respect to CONTROL plants. Yield reduced by 74% and 57% in 0_N and WR, respectively, which also induced a reduction in roots FW, resulting in a significant increase in roots/leaves ratio (0.47 and 0.33 for 0_N and WR, respectively). Conversely, LR favoured the highest leaves fresh weight (FW) (99.89 g plant −1 ) and the lowest root biomass FW (7.50 g plant −1 ); consequently, the roots/leaves ratio was strongly constrained (0.07). The limitation of PAR availability reduced both soluble and bound phenolic compounds as well as antiradical activity. 0_N allowed to obtain the highest total polyphenols content (4.27 mg GAE g −1 FW) and antiradical activity (13.91 μmol TE g −1 FW), although no differences were found in terms of the main phenolic compounds. WR improved the accumulation of caffeic, caftaric and chicoric acids in the bound forms (0.64, 300.85 and 67.38 mg 100 g −1 FW, respectively). PCA analysis significantly explored the correlation between the limiting growing conditions with lettuce yield and quality traits and indicated that water and N fertilization management as the more effective to manipulate the accumulation of plant-based phytochemicals which play an important role in human well-being. [ABSTRACT FROM AUTHOR]

The effect of two conching processes, namely Long Time Conching (LTC) and Short Time Conching (STC), on the content of bioactive compounds and on their activity in chocolate was investigated. The dark chocolates so produced were extracted with both organic solvent and water to investigate the content and different contribution of procyanidins, water-soluble phenolic and melanoidin fractions to the overall antioxidant activity. The procyanidin content and pattern were deeply affected by the different processing conditions: after conching the STC-samples presented a higher amount of monomers compared to the LTC-ones which, in turn, resulted more polymerized as confirmed by the presence of P10 polymers. Both STC- and LTC-products presented comparable phenolic content and FRAP values but products collected at the different conching steps, and in particular during LTC, showed a significant improvement of the radical scavenging properties (TEAC PROC ). The aqueous extract showed a lower antioxidant activity compared to TEAC PROC . Based on the analysis of the melanoidin fraction, no further development of Maillard reaction occurred as a consequence of conching. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mechanical and structural properties were affected by process, frozen state and sugar enrichment. [•] SEM analysis evidenced a thermoprotective effect of sugars on over-blanched carrots. [•] SEM analysis showed a cryoprotective effect exerted by sugars upon frozen storage. [•] Trehalose thermo-protection on PE limits the cryo-protection on frozen samples. [•] Trehalose showed a cryo-protective effect in frozen samples with inactivated PE. [ABSTRACT FROM AUTHOR]

Highlights: [•] Water activity is not strictly related to enzymatic activity in solutions. [•] Water mobility is not strictly related to enzymatic activity in solutions. [•] Enzyme activity mainly depends on viscosity regardless of water activity. [•] Viscosity being equal, the solute molecular weight affects enzyme activity. [•] The hindrance of enzyme diffusion limits its activity. [ABSTRACT FROM AUTHOR]

• 149 VOCs, of which 13 new compounds, were identified in wheat kernels. • Selected VOCs permitted to discriminate among wheats cultivated in different farms. • Selected VOCs permitted to discriminate among wheats grown at different altitudes. • Selected VOCs permitted to discriminate between durum and common wheat. • Environmental conditions were the highest source of variability in VOCs profile. A deeper knowledge of the causes of volatile organic compounds (VOCs) variance in wheat is crucial for quality improvement and control of its derivatives. The VOCs profile of common and durum wheat kernels grown in different fields sited at different altitudes over two years was analysed and 149 compounds were identified by gas chromatography-mass spectrometry. Principal component analysis evidenced that the year of cultivation was the highest source of VOCs variance. The effects of wheat origin, as described by the cultivation site, its elevation, and species were further investigated by PLS-DA, that permitted to correctly classify wheat of different origin on the basis of its VOCs profile. The importance of the different effects was investigated by multidimensional test and resulted: year of cultivation > field of cultivation > species > altitude. Findings suggest that environmental conditions are more important than species in the determination of the VOCs variance of wheat. [ABSTRACT FROM AUTHOR]

• Altitude is significantly correlated with selected VOCs. • Altitude represents a minor source of variability in VOCs profile. • Altitude is linearly correlated to changes in VOCs profile. • A VOCs combination permitted to predict altitude in durum and common wheat. • A VOCs combination permitted to classify durum and common wheat on the basis of altitude. The cultivation of crops at high elevations in response to climate changes leads to modifications in the volatile organic compounds (VOCs) profile. The VOCs profile of common and durum wheat grown in different fields sited at three different elevations over two years was analysed. Partial least square analysis (PLS2) evidenced the effect of altitude on VOCs variance that was hidden among others (cultivation year, species, farm) not correlated with it. PLS1 analysis was further carried out using VOCs as explanatory variables and altitude as dependent variable to find the linear combination of VOCs able to continuously predict the altitude of samples. Selected VOCs, related to biotic, abiotic and oxidative stress conditions, could describe the changes in VOCs profile of wheat induced by altitude increase. Furthermore, common and durum wheat showed different responses to stress at high altitude. These results could be considerably useful for wheat product classification and authentication. [ABSTRACT FROM AUTHOR]

Abstract: The radical scavenging activity (RSA) of coffee brews obtained from different types of coffee was studied as a function of the roasting degree and equivalent thermal effect (expressed as ), and the relative contribution of the phenolic fraction (PF) and non-phenolic fraction (NPF) to the overall RSA was evaluated. Brews extracted from medium roasted coffee showed a higher RSA than those from green coffee due to an increase of the RSA of the NPF upon roasting. The RSA of the NPF increased with increasing roasting degree together with the accumulation of brown coloured Maillard reaction products (MRPs). Brews from dark coffee showed lower RSA than those from medium roasted coffee due to polyphenols degradation which, in turn, caused an RSA depletion not counterbalanced by an increase of the RSA of NPF. The relative contribution of NPF to the overall RSA of the brew is in fact much lower than that of the PF. Roasting processes with similar values resulted in the same RSA independent of an average temperature variation from 170 to 190°C and coffee type. The AOA changes in brews from commercial coffee samples (medium and dark roasted) were more dependent on roasting severity than on the type of coffee. [Copyright &y& Elsevier]

Abstract: A method for the determination of six phthalate esters in wine samples has been developed. The phthalates were extracted from wine samples with an optimised solid-phase extraction method on C18 column and quantification was achieved via gas chromatography coupled with a mass spectrometer. The method was linear between 0.015 and 5.000μgmL−1 for DMP, DEP and DEHP and between 0.018 and 5.000μgmL−1 for iBP, DBP and BBP. The LOQs of DMP, DEP and DEH were 0.024μgmL−1 while those of iBP, DBP and BBP were 0.029μgmL−1. The intra-day method repeatability was between 10% and 15% RSD, whereas the inter-day method repeatability was between 13% and 21% RSD. A survey was performed on white and red wines (n =62) from the market, winemakers and an experimental pilot plant. All the analysed samples were phthalate contaminated. Commercial wine showed higher detection frequency and level of total phthalate, DBP and BBP than those produced in a pilot plant. iBP and DEHP concentrations were similar in all the groups of samples. iBP concentration was higher in red wines than in white ones. [Copyright &y& Elsevier]

Abstract: Biogenic amines are undesirable compounds produced in foods mainly through bacterial decarboxylase activity. No legal limits are given by international institutions but the presence of these substances is a fundamental quality parameter for alcoholic beverages. This work evaluated the interactive effect of some variables on the biogenic amine production of the strain Oenococcus oeni T56. At higher pH values biogenic amines were produced in considerable amount whereas high ethanol concentrations and low concentration of pyridoxal-5-phosphate reduced their accumulation, such as. The roles of arabinose and SO2 are more complex and involve specific pathways rather than whole cellular activity. [Copyright &y& Elsevier]

• ORG and CONV apples showed a different profile in free and conjugated polyphenols. • Total phenolic content and antioxidant activity were similar in ORG and CONV apples. • VI pre-treatment increased the functional properties of ORG and CONV apples. • Freezing differently impaired free and conjugated polyphenols of ORG and CONV fruits. • ORG and CONV apples' response to process-induced physical stresses was different. The effect of pre-treatment (dipping and vacuum impregnation in lemon juice solution), freezing and frozen storage (FS) on single and total polyphenols (free and conjugated) content and antioxidant activity (AOA) of organic and conventional apples, was investigated. Fresh organic and conventional fruits showed different profiles of free and conjugated polyphenols while their total phenolic content and AOA were similar. Organic and conventional apple tissues showed different physiological responses to physical stresses described by changes in phenolic profiles. Vacuum impregnation in lemon juice affected the polyphenols extractability of both the organic and conventional apples and favored their enrichment with bioactive compounds (AOA = +11.5%). FS decreased the single and conjugated polyphenols content of the pre-treated apple samples and the effect was different between organic and conventional fruits. After FS, not pre-treated organic apples showed a lower AOA reduction than the conventional ones (−13% vs −25%), while no differences were found on pre-treated samples. [ABSTRACT FROM AUTHOR]