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In breadmaking, dietary fibres are used to improve the nutritional quality of the final products; on the other hand, they may affect the physical and sensory properties. This work aimed to the evaluate, on pan breads, the effect of substituting 3 g of wheat flour with an equivalent amount of fibre rich ingredients: chestnut peels (CP) or wheat bran (WB), in comparison to a traditional wheat bread formulation (C). The effect of four levels of added water (54, 60, 66, 71 g/100 of flour) was also tested. The fibre content of CP (33%) and WB (42%) affected their water binding capacity and, consequently, the quality of the final loaves, according to the different water addition levels. In bread crumb, water content and water activity increased proportionally to the water addition levels, being instead in the crust also affected by the presence of fibres: lower water retention capacity was observed for CP, in comparison to WB and C. The loaf volume resulted higher for C in comparison to WB and CP, in relation to the larger dimensions of the crumb pores, probably due to the interfering effect of fibres during the development of the gluten network. Crumb hardness resulted higher for C at low water addition levels, being instead higher for CP at high water addition levels. CP showed a darker and redder colour, than both WB and C bread, for the presence of the brown pigments carried by chestnut peels. PCA analysis confirmed that more water is required for both the fibre-enriched breads to show characteristics similar to the control loaves.

A distinguishing quality or characteristics of apple puree was determined considering the effect of different processing practices: thermal (4 T), ohmic heating (OHM) and high-pressure processing (HPP). In the thermal treatment, the flow rate was set to 1700 L/h and SHP was approximately 40 s; HPP was conducted at 600 MPa for 3 min and ohmic heating at a flow rate of 2000 L/h, at 107 °C (sample preheated from 25 to 60 °C). Effects on colour, viscosity, particle size distribution (PSD), total phenol content (TPC), ascorbic acid content and sensorial quality were comparatively studied. Results showed that a very low reduction of ascorbic acid in HPP is observed. The highest ascorbic acid loss was observed for 4 T and in a lower extent for OHM ascribable to the thermal degradation, as hypothesized for pigments. The TPC content was not changed during processing. The other quality parameters evaluated (viscosity, colour, PSD, turbidity, consistency, sensorial analysis) were affected by treatments, with particular reference to 4 T. This is one of the first study applying commercial industrial-scale equipment’s. Concluding, as compared to 4 T, OHM and HPP demonstrated feasible technologies for the treatment of apple puree, having obtained also a good organoleptic response. Apple puree preparation by means of high-pressure processing, ohmic or mild thermal treatments could imply new opportunities for the apple processing industry in developing more fresh like value-added products with reasonable shelf life.

In response to the market demand for low processed vegetables, high-pressure treatments (400,600 MPa; 1,5 min) were applied on zucchini slices and compared to a traditional blanching treatment. Histological observations, texture and color analysis, pectinmethylesterase (PME) and antioxidant (DPPH) activities were measured and compared to untreated samples. The histological observations revealed that the longer high-pressure treatments (5 min) led to more extended cell lysis and dehydration than the shorter ones (1 min) and blanching. High-pressure treatments resulted less effective than blanching on PME inactivation, with the best results obtained at 400 MPa for 1 min. Comparable texture parameters were observed for high-pressured and blanched samples. The negative correlation found between PME activity and the texture parameter ‘distance of the first peak force’ revealed an effect of PME on the texture recovery after treatments. High pressure led to a general browning of zucchini parenchyma and to DPPH drop. The correlations found between DPPH and color suggest the common nature of the phenomena. The influence of pressure and time on the studied parameters was revealed by two-way ANOVA. Principal component analysis clustered together the four high-pressure-treated samples, being clearly divided by blanched and untreated ones.

Cocoa bean shells (CBS) are by-products of cocoa processing. Their rich chemical composition makes them interesting ingredients to improve the overall quality of gluten free bread. The addition of different dimensional fractions (F1, 1.00–1.99 mm; F2, 0.50–0.99 mm; F3, 0.355–0.49 mm) of CBS to gluten-free bread was investigated in terms of volume, moisture content, crumb grain, texture and colour during 3 days of storage. No significant differences in moisture content were observed among fractions, but protein, fat and fibre content resulted influenced by the dimensional range. With reference to water absorption indexes, F2 showed the highest water binding capacity (WBC) and water holding capacity (WHC), having instead the lowest water solubility index (WSI), in comparison with the other fractions, and confirming a good retention of the fibres’ structure. Results on bread showed that CBS addition modified crumb grain leading to a lower specific volume, especially for F2. The presence of CBS accelerated significantly the crumb staling process in comparison with the control, resulting; however, F1 softer than control at the end of the storage period. Finally, colour was improved by the presence of CBS becoming darker, with F3 showing the highest impact on L* and a*.

In this work, differential scanning calorimetry (DSC) was for the first time applied to evaluate cooling and heating curves and related thermal properties of olive oil during refining process steps starting from two series of samples at different initial peroxide values (low, 15meqO2/kg and high, 30meqO2/kg). Thermal properties were statistically correlated by means of principal component analysis (PCA) to those substance classes (products deriving from oxidation, polymerization and hydrolysis of triacylglycerols (TAG)) that could exert adverse effects on consumer health and a negative contribution to the shelf-life of the refined oil. A concomitant significant increase of K270 and polymerized TAG, as a general decrease of oxidation level was exhibited by oils during bleaching. Crystallization significantly shifted towards lower temperatures as well as onset temperature of heating, enlarging transition range, starting from bleaching and at both oxidation levels. PCA was performed to tentatively discriminate among samples according to different refining steps and/or initial level of oxidation correlating thermal properties and chemical results. The first principal component clearly clustered samples according to different refining steps and this differentiation was possible on the basis of the relation of thermal parameters with polymerized TAG conjugated dienes and trienes (K232 and K270, respectively). This preliminary goal should lead to deepen the study of DSC application in the evaluation of the quality of olive and other vegetable oils during refining. Practical applications: DSC is a thermal technique that nowadays covers a large set of applications in lipid technology due to its indisputable advantages as it does not require sample preparation and use of solvents, resulting in a reduced environmental impact. The preliminary findings of this study promote the application of the technique in the evaluation of olive oil quality during refining steps in relation with molecular species formed as polymerized TAG and conjugated trienes discriminating crude and neutralized samples to bleached and deodorized oils. DSC could be also applied on other vegetable oils where refining process is more frequently applied. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Looking at the olive oil production, the final extraction phase from the paste affects the yield and the quality of the oil more than other processing steps. Several strategies are therefore applied today to increase the process outcome already before extraction at the malaxation stage. Technical innovation is particularly realized in adopting olive oil decanters that enable real-time adjustments of working parameters in function of the different composition of the raw materials, improving the yield of the process and avoiding a significant economic loss for the sector. In the paper of Caponio, Summo, Paradiso and Pasqualone published in this issue of the European Journal of Lipid Science and Technology [1626–1633], the performance of the so-called “third generation” decanter is presented showing the impact of its application on the chemical, nutritional, olfactory and sensorial quality in the sector of olive oil processing. The significance of the achieved results is underlined in the following commentary.

Thirteen monovarietal extra virgin olive oils (EVOos) from two Italian regions were evaluated by means of differential scanning calorimetry (DSC) to study statistical correlations among major and minor chemical components and thermal properties obtained by cooling transitions and their deconvoluted peaks. The application of DSC for the discrimination of EVOos according to the cultivar and geographical origin was also considered. Thermal properties of the cooling transitions (except for the crystallization enthalpy) were almost all influenced by triolein content and fatty acid composition. Thermal properties (area, onset and offset temperatures of transition, transition range, and peak temperature) of the three deconvoluted peaks were found to be significantly correlated not only to major but also to minor components (diacylglycerols, free fatty acids) and oxidative stability indices. The analysis of thermal properties obtained by cooling transition did not lead to sample discrimination according to geographical provenience. However, Ton, Toff, and peak areas of the two deconvoluted transitions that peaked at the lowest temperatures, as well as Toff of deconvoluted peak at the highest temperature, significantly differentiated oil samples according to their geographical origin. These findings may be confirmed by the appliance of multivariate statistical analysis to a larger set of samples to select thermal parameters able to discriminate among EVOos of different geographical provenience. Practical applications DSC application exhibits some advantages upon the classical analytical methods as it does not require sample preparation and use of solvents, thus resulting in a reduced environmental impact. The results of this study suggest that DSC can be used to test quality and to determine geographical origin of EVOo.

Thermal decomposition of 12 monovarietal extra virgin olive oils from different geographical origins (eight from Italy, two from Spain, and the others from Tunisia) was evaluated by simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC) analyses. All extra virgin olive oils showed a complex multistep decomposition pattern with the first step that exhibited a quite different profile among samples. Thermal properties of the two peaks obtained by the deconvolution of the first step of decomposition by DSC were related to the chemical composition of the samples (triacylglycerols, fatty acids, total phenols and antioxidant activity). Onset temperatures of the thermal decomposition transition and T(p) values of both deconvoluted peaks as well as the sum of enthalpy were found to exhibit statistically significant correlations with chemical components of the samples, in particular palmitic and oleic acids and related triacylglycerols. Activation energy values of the second deconvoluted peak obtained by the application of kinetic procedure to the first step of decomposition were also found to be highly statistically correlated to the chemical composition, and a stability scale among samples was proposed on the basis of its values.

Application of differential scanning calorimetry (DSC) to discriminate among extra virgin olive oils on the basis of cultivar–environment interaction was preliminary evaluated on Tunisian samples from two varieties (Chetoui and Chemlali) and different geographical origin relating thermal properties obtained by cooling and heating thermograms to chemical composition. Higher content of triunsaturated triacylglycerols and oleic acid and lower amount of palmitic acid were detected in Chetoui samples in comparison with Chemlali oils. Cooling thermograms exhibited two well distinguishable exothermic peaks in all samples; the major event at lowest temperature was taller and sharper in Chetoui samples whereas the other peaking at highest temperature was more evident for Chemlali oils. Crystallization enthalpy did not account for the differences observed in chemical composition between the two cultivars. On the contrary, T on and T off of crystallization were found to significantly differ according to the compositional differences due to cultivars and geographical provenience interaction. Heating profiles exhibited a minor exothermic peak followed by multiple endothermic events and appeared also distinctive of oil samples from two cultivars. All thermal properties obtained by the analysis of heating thermograms significantly differed among oil samples from different geographical provenience. The application of DSC appeared useful to differentiate samples of different cultivars and/or geographical proveniences.

Thermal properties of monovarietal extra virgin olive oils were evaluated by means of differential scanning calorimetry (upon cooling) and related to their chemical composition (triacylglycerols, diacylglycerols, total and free fatty acids, oxidation status). The overall crystallization enthalpy did not significantly differ among samples and did not account for the differences observed in chemical compositions. On the contrary, a higher degree of unsaturation in the lipid profile induced a shift of the crystallization onset towards lower temperatures and narrowing of the crystallization temperature range. The presence of triacylglycerol lysis and lipid oxidation products shifted the crystallization towards higher temperatures and the phase transition developed over a larger temperature range. Differential scanning calorimetry thermograms were deconvoluted into three constituent exothermic peaks for all samples. The area of the two lower-temperature exotherms was found to be statistically correlated with the amount of triunsaturated and monosaturated triacylglycerols present in the oil. Thermal properties of extra virgin olive oil were found to be affected by oil chemical composition.

No literature data were available on the crystal polymorph structure associated with the crystallization/melting of TAG fractions of extra virgin olive oil until the publication of the article by Barba, Arrighetti and Calligaris in this issue of the European Journal of Lipid Science and Technology [p. 322–329]. The authors determined crystal structure of extra virgin olive oil TAGs using DSC coupled with XRD technique. These findings are of great importance as an increasing number of formulated foods (e.g. salad dressings, sauces, chilled and frozen ready-to-eat products) and new products are nowadays produced with this high quality vegetable oil as lipid phase. The significance of these results is underlined in this commentary. See accompanying article by Barba et al. [p. 322–329], http://dx.doi.org/10.1002/ejlt.201200259

A simple and rapid method for the determination of ochratoxin A (OA) in ham was developed using a basic methanolic extraction, immunoaffinity column clean-up and a fluorometric determination of the toxin contamination levels. A mean recovery of OA from ham samples spiked at levels from 0.7 to 9.7 microg kg(-1) was 83 +/- 6% using the fluorometric method, with a detection limit of 0.7 microg kg(-1). Recovery data were compared statistically with those obtained using reversed-phase high-performance liquid chromatography with acetonitrile-water-acetic acid (99:99:2) as mobile phase and fluorescence detection, commonly used for OA determination in food. A good correlation between the two analytical techniques was obtained. Both methods were successfully applied to 42 ham samples, 21 in the middle of the ripening period (after 6 months from the process beginning) and the other 21 at the end of the maturation, after 12 months. Twenty-seven samples (64%) showed an OA contamination level1.0 microg kg(-1), the Italian Ministry of Health guideline. The maximum contamination level found was 2.3 microg kg(-1). A good agreement (R(2) = 0.980) between HPLC and fluorometer analysis on naturally contaminated samples was obtained.

The deep changes caused by oxidation on virgin olive oil (VOO), which is a high-quality product, not subjected to ameliorative refining, make this phenomenon one of the most studied. Among the techniques used to study oxidation in olive oil, thermal analysis (TA) provides useful information about the thermal behavior of the samples as affected by oxidation. Thermogravimetry (TG), measuring the changes in the sample mass, can monitor the kinetics of oil mass loss in decomposition processes or oxidation and has been found particularly useful, especially when operating simultaneously with Differential Thermal Analysis (DTA) or Differential Scanning Calorimetry (DSC). The DSC thermal curves of olive oil, both on cooling and heating, has been found to be largely influenced by the oxidative status of the samples and different statistical approaches have been successfully proposed to correlate the thermal parameters with the conventional chemical indicators of oxidation. DSC can be also used to study the kinetics of phase transition phenomena as affected by oxidation. This review provides an exhaustive survey about the application of the thermoanalytical techniques on this topic proposing them as as a fast and green alternative to conventional chemical methods. 2 Practical applications: The evaluation of the oxidative status of olive oil requires the development of simple and fast analytical techniques. The most used analytical methods are based on the chemical evaluation of the presence of molecules markers of lipid oxidation, but thermal analysis may provide a fast and green tool in this field, as it does not require sample preparation and use of solvents. The application of thermal analysis for the assessment of the oxidative degradation of olive oil has today reached numerous evidences that attest its actual applicability, and they are all summarized in this review. By these studies it is possible to put in evidence its ability to give qualitative information about the oxidative status of olive oil, both in terms of fatty substance degradation and presence of oxidation molecules that could be very helpful in the field of quality assurance for this high-quality vegetable oil. Thermal analysis as a valuable tool to evaluate olive oil oxidation without sample preparation or use of solvents.

Three extra virgin olive oils having different fatty acid compositions and total phenol contents were submitted to an accelerated storage test at 60°C for up to 21 weeks. Their oxidative status, evaluated by peroxide values and total phenolic content, was related to differential scanning calorimetry cooling profiles and thermal properties. Changes in crystallization profiles were consistent starting from 12 weeks for the two oil samples (B and C) that had a higher content of linoleic acid and medium/low amounts of phenols, respectively, whereas they became detectable at the end of the test for the remaining oil (sample A). Decrease of crystallization enthalpy and shift of transition towards lower temperature were also evident at 4 weeks of storage for samples B and C, whereas the same changes in the transition profile were noticeable at 12 weeks for sample A. Differential scanning calorimetry appears to be suitable for the discrimination of oxidative status of extra virgin olive oils with widely different fatty acid composition.

Phytochemicals (carotenoids, phenolic compounds, and ascorbic acid) and antioxidant capacity (measured by TEAC, FRAP, and TRAP assays) were evaluated on carrots and Brussels sprouts sous vide processed and then stored refrigerated for 1, 5, and 10 days and compared with the corresponding raw and oven-steamed products. Data showed that sous vide cooked carrots had higher amounts of carotenoids, phenolic compounds, and ascorbic acid than steamed products, and only a slight decrease of phenolic compounds was recorded during sous vide storage. Contrasting results were obtained on sous vide processed Brussels sprouts: higher carotenoid amounts and TEAC and TRAP values and lower phenolic compounds, ascorbic acid, and FRAP values were exhibited by sous vide in comparison with steamed samples. Phytochemicals and TAC also decreased during Brussels sprout sous vide storage with the exception of carotenoids. The results of this study demonstrated that sous vide preparation can preserve and/or enhance the nutritional quality of carrots, which remain a good source of carotenoids also after long refrigerated storage, whereas the same treatment could be recommended as an alternative to oven-steaming in the preparation of Brussels sprouts for short-term maintenance to avoid a large ascorbic acid depletion.

In this work, a multidisciplinary approach for the evaluation of extra virgin olive oil traceability (geographical provenience and botanical differentiation) is presented. Conventional techniques such as major chemical component determination (triacylglycerols, TAG and fatty acids) and other novel approaches as stable isotopic ratio (13C/12C in combination with 18O/16O) and thermal properties obtained from cooling curves and their deconvoluted peaks by means of differential scanning calorimetry were compared. Fifty-three samples from different Italian regions, diverse cultivars, and two Mediterranean areas (Italy and Croatia) were analyzed with all the three techniques. The oils exhibited different values especially for δ18O and thermal properties of the deconvoluted peaks of crystallization according to Italian regions and/or cultivars. Data were treated by means of linear discriminant analysis inserting all parameters as predictors in models where the potentiality to discriminate oils was tested. All models revealed a good resolution among categories with selected TAG, δ18O values, and thermal properties of the deconvoluted peak set at the highest temperature exhibiting the highest weight for the discriminant functions. These findings could give strength to the utilization of new analytical techniques supporting those traditionally employed, also sustained by proper chemometric procedures, as suitable for the resolution of extra virgin olive traceability. Practical applications: Consumers' awareness of extra virgin olive oil traceability has recently increased the interest for new methods that can assess its geographical and botanical origins and new findings in this sector represent a key factor affecting the purchases in non-producer countries. Multidisciplinary approaches supported by chemometric procedures enable the building of large databases and classification models for the determination of the provenience of extra virgin olive oil.

This study evaluated the effect of common cooking practices (i.e., boiling, microwaving, and basket and oven steaming) on the phytochemical content (carotenoids, chlorophylls, glucosinolates, polyphenols, and ascorbic acid), total antioxidant capacity (TAC), and color changes of three generally consumed Brassica vegetables analyzed fresh and frozen. Among cooking procedures, boiling determined an increase of fresh broccoli carotenoids and fresh Brussels sprout polyphenols, whereas a decrease of almost all other phytochemicals in fresh and frozen samples was observed. Steaming procedures determined a release of polyphenols in both fresh and frozen samples. Microwaving was the best cooking method for maintaining the color of both fresh and frozen vegetables and obtaining a good retention of glucosinolates. During all cooking procedures, ascorbic acid was lost in great amount from all vegetables. Chlorophylls were more stable in frozen samples than in fresh ones, even though steaming methods were able to better preserve these compounds in fresh samples than others cooking methods applied. The overall results of this study demonstrate that fresh Brassica vegetables retain phytochemicals and TAC better than frozen samples.

In this study, mildly deodorized olive oil (DEO) and its admixtures with extra virgin olive oil (EVOO) have been analyzed after heating treatments by microwave and conventional oven. Different patterns in oxidative and hydrolytic degradation of lipids in genuine and sophisticated olive oils have been evaluated by chromatographic and spectroscopic methods and related to heating treatments. The experimental plan focused on the assessment of the (a) hydrolytic degree of the samples by the free acidity and the 1,2- and 1,3-diacylglycerols (DAG) determinations; (b) oxidative status of the samples by the assessment of the peroxide value (POV) and oxidized fatty acid (OFA), the specific absorption at 270 nm (k(270)), the accelerated aging test (OSI) and volatile compounds. In general, the thermal treatment by conventional oven led to a higher content of 1,3-DAG and secondary oxidation products than microwave heating. A duo-trio sensory test was also performed: tasters were not able to discriminate between EVOO and DEO heated by conventional oven whereas they were when oils were microwaved.

Chemical changes produced in an extra virgin olive oil sample in the presence (EVOO) and absence (EVOOP) of its phenolic fraction during an accelerated storage treatment at 60 degrees C up to 7 weeks were studied. Modifications in phenol content, as well as changes in several quality parameters (free acidity, peroxide value, UV absorbance, fatty acid composition, oxidative stability index, and tocopherol content) were also evaluated under the same storage conditions and compared to those of the same sample deprived of phenolic compounds. When the phenolic extract of the EVOO was studied, a decrease of the antioxidants first present in the sample and an increase of the oxidized products were observed. In addition, oxidation seemed to produce the transformation of such phenolic compounds as secoiridoids and the appearance of oxidized forms of them. These latter compounds could be used as molecular markers of the lack of extra virgin olive oil freshness.

Differential scanning calorimetry (DSC) was employed to detect high oleic sunflower oil (HOSo) as an adulterant in extra-virgin olive oil (EVOo) by means of cooling and heating thermograms. Addition of HOSo did not significantly alter cooling profiles of EVOo except for onset temperature of crystallization, which was significantly shifted toward lower temperature at 40% of adulterant addition. At the same percentage of adulteration, the heating profile of EVOo was significantly changed as the major endotherm broadened and the minor event became smaller and less evident. Cooling thermograms of pure oils and their admixtures were deconvoluted into three constituent exothermic peaks in an attempt to detect addition of HOSo at levels lower than 40%. Thermal properties of the two lower-temperature exotherms (area percentage, offset temperature and range of transition) were significantly changed at≥20% of HOSo substitution, suggesting that DSC can be employed to detect this oil as an EVOo adulterant. PRACTICAL APPLICATIONS Adulteration of extra-virgin olive oil (EVOo) with cheaper oils from other vegetable sources or seeds, as well as with lower quality olive oils, is a serious concern for oil suppliers and consumers and requires the use of new analytical techniques for their detection. Differential scanning calorimetry (DSC) exhibits some advantages over the classical analytical methods as it does not require sample preparation and use of solvents, thus resulting in a reduced environmental impact. Results suggested that its application to the detection of EVOo adulteration with high oleic sunflower oil, a vegetable oil largely employed for this type of fraud, is promising with the support of the deconvolution analysis of cooling thermograms.

Extra virgin olive oils from drupes of three Sicilian varieties (Biancolilla, Cerasuola and Nocellara del Belice) and collected at three different harvesting periods, were analyzed upon heating by means of DSC and thermal properties were related to the chemical composition of the samples. All thermograms exhibited multiple transitions with a minor exothermic peak, followed by a major endothermic event. Cerasuola samples showed higher overall enthalpy and narrower range of transition at all harvesting periods, as compared to the other oils. A more ordered crystal structure originating from a more uniform chemical composition, with higher triolein content, in Cerasuola, may be hypothesized. At different harvesting periods, thermal transitions started at lower temperatures and developed over a narrower range in all cultivars, probably due to the insertion of molecules derived from triacylglycerols lysis (diacylglycerols and free fatty acids) and lipid oxidation products into the triacylglycerol crystal lattice. All heating thermograms were deconvoluted into one exothermic and five endothermic constituent peaks and the effect of chemical components on thermal properties of the peaks was evaluated. DSC application upon heating appears to be very promising in discriminating among oil samples from olives of different cultivars and/or harvesting periods.

The objective of the present study was to evaluate the effect of three common cooking practices (i.e., boiling, steaming, and frying) on phytochemical contents (i.e., polyphenols, carotenoids, glucosinolates, and ascorbic acid), total antioxidant capacities (TAC), as measured by three different analytical assays [Trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP), ferric reducing antioxidant power (FRAP)] and physicochemical parameters of three vegetables (carrots, courgettes, and broccoli). Water-cooking treatments better preserved the antioxidant compounds, particularly carotenoids, in all vegetables analyzed and ascorbic acid in carrots and courgettes. Steamed vegetables maintained a better texture quality than boiled ones, whereas boiled vegetables showed limited discoloration. Fried vegetables showed the lowest degree of softening, even though antioxidant compounds were less retained. An overall increase of TEAC, FRAP, and TRAP values was observed in all cooked vegetables, probably because of matrix softening and increased extractability of compounds, which could be partially converted into more antioxidant chemical species. Our findings defy the notion that processed vegetables offer lower nutritional quality and also suggest that for each vegetable a cooking method would be preferred to preserve the nutritional and physicochemical qualities.

In this study, the effects of three common cooking practices (i.e., boiling, steaming, and frying) on the artichoke phenolic compounds pattern were evaluated by LC-MS/MS analysis. The variation of carotenoids, antioxidant capacity, and artichoke physical properties after cooking was also investigated. The major phenolic compounds present in the raw sample were 5- O-caffeoylquinic and 1,5-di- O-caffeoylquinic acids; after cooking treatments, an increase of the overall caffeoylquinic acids concentration due to the formation of different dicaffeoylquinic acid isomers was observed. Steamed and fried samples showed similar patterns of dicaffeoylquinic concentrations, which were higher with respect to the boiled samples. On the other hand, all cooking practices, particularly frying, decreased flavonoid concentration. The antioxidant capacity of cooked artichokes, measured by three different assays, enormously increased after cooking, particularly after steaming (up to 15-fold) and boiling (up to 8-fold). The observed cooking effect on the artichoke antioxidant profile is probably due to matrix softening and increased extractability of compounds, but the increase of antioxidant capacity is much higher than the increase of antioxidant concentration. These results suggest that some common cooking treatments can be used to enhance the nutritional value of vegetables, increasing bioaccessibility of health-promoting constituents.

Gelatinization of tapioca starch (25% dry basis) was induced by high hydrostatic pressure processing (HPP) at 600 MPa under different time and temperature regimes (30 °C for 10, 20 and 30 min; 50 °C for 10 min; 80 °C for 10 min). Textural, thermal and structural properties of the gels were studied and their stability was evaluated after 28 days of refrigerated (4 °C) and frozen (−18 °C) storage. Thermally induced gels (90 ± 1 °C, 20 min, gel-T) were used as controls. HPP resulted in the formation of harder gels than thermal processing (more significantly at lower processing temperatures) partially preserving the granular structure of the native starch. Longer HPP treatments caused only a slight decrease in hardness that was significant only at longer processing times (30 min). DSC thermograms of high pressure-induced samples showed a more asymmetrical ice-melting peak than that of thermally induced gels. Asymmetry of the peak of HP treated samples was more pronounced in samples processed at lower than at higher temperature. A different starch–water and/or starch/starch interaction may be hypothesized. During storage, all samples became stiffer and the amylopectin recrystallization increased, more extensively in thermally induced than in HPP samples where a stronger starch–starch and/or starch/water interactions may have hindered the recrystallization process.

The ability of three commercial inulins (Raftilose ®P95, Frutafit IQ®, and Frutafit TEX®) with different chemical composition (oligo-polysaccharides profile) to form gels (at 25 and 50 °C) was evaluated. Raftilose®P95 (rich in mono-disaccharides) did not form gels, Frutafit IQ® (mainly oligosaccharides) gelatinized in the 30–60% w/w concentration range and Frutafit TEX® (mainly long-chain saccharides) in the 20–40% w/w range. Textural and thermal properties of the gels were studied and their stability was evaluated during storage at 4 °C. Frutafit TEX® gels (both fresh and during storage) were harder, more adhesive, and less cohesive than Frutafit IQ® gels (40% w/w). At 40% w/w, Frutafit TEX® gels had a significantly higher amount of freezable water than Frutafit IQ®, and the DSC thermogram line shapes indicated that ice melting was more uniform and occurred at higher temperatures in Frutafit TEX® than in the Frutafit IQ® gels. Ice melting profile was not significantly affected by both gelification temperature and storage time. Frutafit IQ® gels were more stable than Frutafit TEX® gels during storage.

An improved analytical method for aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1) determination in pig liver is described, using an aqueous methanol extraction, an immunoaffinity column clean-up step and a direct fluorometric measurement for toxin detection and quantification. A detection limit of 1.0 microg kg-1 was achieved for AFB1 and AFM1. Mean recoveries of 80.7+/-9.0% for AFB1 spiked at 1.0-9.7 microg kg-1 levels and of 76.7+/-6.6% for AFM1 spiked at 1.0-5.5 microg kg-1 levels were obtained. Recovery data for spiked samples were statistically compared with those obtained by the same extract using classical reversed-phase high-performance liquid chromatography (RP-HPLC) with fluorescence detection, showing a significant correlation (por=0.05) for both aflatoxins. Both procedures were applied to the analysis of 50 pig livers, collected from 10 farms in the north of Italy. All the samples showed a contamination level lower than 1.0 microg kg-1 for AFB1 and one liver sample has shown an AFM1 contamination greater than 1.0 microg kg-1. The direct fluorometric procedure is particularly suitable for food manufacturers and control laboratories where quick procedures are mainly required for food quality control as well as for diagnostic and research purposes.