Chemical, microbiological, textural, and sensory characteristics of pilot-scale Caciofiore cheese curdled with commercial Cynara cardunculus rennet and crude extracts from spontaneous and cultivated Onopordum tauricum.

The aim of this study was the chemical, microbiological, textural, and sensory characterization of pilot-scale prototypes of an Italian ewe's raw milk cheese (Caciofiore) curdled with commercial Cynara cardunculus rennet, used as a control, and crude extracts obtained from flowers of either spontaneous or cultivated Onopordum tauricum. Hence, the control and experimental cheese prototypes produced in two rounds of cheesemaking trials were assayed, at the end of their 60-day maturation, for the following features: pH, titratable acidity, dry matter, fat, total and soluble nitrogen (TN and SN, respectively), ash, salt, protein, lactose, viable plate counts and composition of the bacterial and fungal populations, color, texture, volatile organic compounds (VOCs), and olfactory attributes by sensory analysis (the latter for the sole prototypes curdled with the commercial rennet and the extract obtained from cultivated O. tauricum). The data overall collected showed a very low impact of the type of thistle rennet on the analyzed cheese traits, with significant differences being exclusively found for SN/TN%, titratable acidity, color, and adhesiveness. By contrast, a higher impact of the cheesemaking round was seen, with significant differences being observed for salt content, load of presumptive lactobacilli, thermophilic cocci, and Escherichia coli, and levels of the following VOCs: 2,3-butanedione, 2-pentanone, 1-butanol, 2-heptanone, 3-methyl-1-butanol, 2-heptanol, 2-nonanone, dimethyl trisulfide, 2-methyl propanoic acid, butanoic acid, and 3-methyl butanoic acid. Sensory analysis revealed a strong ewe's cheese odor, accompanied by other olfactory notes, such as pungent, sour curd, sweet, and Parmesan cheese-like notes, in all the analysed cheese prototypes. Moreover, key odor active compounds, including butanoic acid, ethyl butanoate, 2,3-butanedione, 1-octen-3-one, and dimethyl trisulfide, were identified by GC-olfactometry analysis. Regarding the odor attributes as determined by sensory analysis, again the type of rennet had an almost negligible impact, with significant differences being only perceived for 1 or 2 out of 20 odor attributes, depending on the analytical conditions applied. Although some aspects deserve further investigation, the results herein collected confirm that O. tauricum can be regarded as an alternative source of thistle rennet for the manufacture of Caciofiore cheese, and more in general, Mediterranean ewe's milk cheeses.

Effect of Different Soil Treatments on Production and Chemical Composition of Essential Oils Extracted from Foeniculum vulgare Mill., Origanum vulgare L. and Thymus vulgaris L.

The aim of the study was to investigate how essential oil production and associated chemical composition and related biological activity could be influenced by different cultivation treatments and distillation methods. Foeniculum vulgare Mill. (fennel), Origanum vulgare L. (oregano) and Thymus vulgaris L. (thyme) were cultivated in absence of any fertilizer (control) and in presence of three different fertilizers: a chemical one with augmented mineral phosphorus and potassium, a second added with hydrolyzed organic substance and mineral phosphorus and potassium (organic-mineral) and a third one treated with a high content of organic nitrogen of protein origin (organic). The plants were subjected to steam distillation using two modalities, recycled and continuous, to obtain 32 essential oil samples. Chemical composition analysis was performed using gas chromatography-mass spectrometry; in vitro antimicrobial activity was evaluated using a broth microdilution method. In general, the recycled distillation method appeared to have a slightly higher yield than the continuous method. The "mineral" and "organic-mineral" treatments resulted in a higher yield compared to the "organic" or "control" treatments, and this was particularly evident in the recycled method. The "control" plants had a lower yield of essential oils. Anethole (13.9-59.5%) and estragole (13.4-52.2%) were the main constituents of the fennel oils; p-cymene and its derivatives carvacrol and thymol were the main constituents of the oregano and thyme samples. The antimicrobial activity of the thyme oils on Staphylococcus aureus ranged from 0.31 to 0.16% (v/v); a lower effect of the oregano samples and no activity of the fennel samples were observed. The essential oils failed to inhibit the growth of Pseudomonas aeruginosa strains.

Chemical Composition and Biological Activities of Essential Oils from Origanum vulgare Genotypes Belonging to the Carvacrol and Thymol Chemotypes.

The remarkable biological activities of oregano essential oils (EOs) have recently prompted a host of studies aimed at exploring their potential innovative applications in the food and pharmaceutical industries. The chemical composition and biological activities of EOs from two Origanum vulgare genotypes, widely cultivated in Sicily and not previously studied for their biological properties, were characterized. Plants of the two genotypes, belonging to the carvacrol (CAR) and thymol (THY) chemotypes and grown in different cultivation environments, were considered for this study. The chemical profiles, including the determination of enantiomeric distribution, of the EOs, obtained by hydrodistillation from dried leaves and flowers, were investigated by GC-MS. Biological activity was evaluated as antimicrobial properties against different pathogen indicator strains, while intestinal barrier integrity, reduction in pathogen adhesion and anti-inflammatory actions were assayed in the intestinal Caco-2 cell line. The chemical profile of the CAR genotype was less complex and characterized by higher levels of the most active compound, i.e., carvacrol, when compared to the THY genotype. The enantiomeric distribution of chiral constituents did not vary across genotypes, while being markedly different from that observed in Origanum vulgare genotypes from other geographical origins. In general, all EOs showed high antimicrobial activity, both in vitro and in a food matrix challenge test. Representative EOs from the two genotypes resulted not altering epithelial monolayer sealing only for concentrations lower than 0.02%, were able to reduce the adhesion of selected pathogens, but did not exert relevant anti-inflammatory effects. These results suggest their potential use as control agents against a wide spectrum of foodborne pathogens.

Exploring volatile aroma and non-volatile bioactive compounds diversity in wild populations of rosemary (Salvia rosmarinus Schleid.).

Ninety-five rosemary (Salvia rosmarinus Schleid.) genotypes, representing 24 wild populations, collected in different geographical areas in Italy and then cultivated under homogeneous environmental conditions, were characterised for volatile organic compounds (VOCs) and three main non-volatile phenolic diterpenes (carnosic acid, carnosol) and acids (rosmarinic acid). Cluster analysis of chemical data highlighted the occurrence of three main groups of populations: one with high levels of verbenone, α-pinene, bornyl acetate, carnosic acid and carnosol, a second one with relatively high levels of camphor and a third one with high levels of 1,8-cineole, ß-pinene and sesquiterpenes. This clustering was consistent with geographic origin and previous genetic characterisation of the same populations. Correlation analysis suggested that levels of the key antioxidant carnosic acid were associated to levels of the key aroma compound verbenone. The observed diversity may be exploited in breeding programs to develop lines and designing products with improved flavour quality and functional properties.

Impact of sodium reduction strategies on volatile compounds, sensory properties and consumer perception in commercial wheat bread.

The efficacy of two sodium reduction strategies in preserving sensory profile and consumer liking of yeasted wheat bread was tested, by combining sensory data, aroma compounds and consumer investigations. The use of (i) a reduced-sodium salt substitute, Pansalt® (NaCl 57%, other salts and minor ingredients) at 1.5%, and (ii) the heterogeneous NaCl distribution (average level of 1%) leading to enhanced saltiness by taste contrast, were compared with standard (1.5%) and reduced (1.0%) addition of NaCl. The heterogeneous NaCl distribution was effective in preserving saltiness. Salt substitution with Pansalt® was less effective but preserved the overall flavour. Higher amount of Maillard reaction volatile products, associated with more intense toasted odour of the crust, was found in breads with higher NaCl content. The consumer survey highlighted satisfactory results of Pansalt® use for 58% of the respondents (equal or higher liking and purchase intention). Heterogeneous salt distribution was effective for 31% of consumers.

Characterization of volatiles and identification of odor-active compounds of rocket leaves.

The volatile profile of crushed rocket leaves (Eruca sativa and Diplotaxis tenuifolia) was investigated by applying Headspace Solid-Phase MicroExtraction (HS-SPME), combined with GC-MS, to an aqueous extract obtained by homogenization of rocket leaves, and stabilized by addition of CaCl2. A detailed picture of volatile products of the lipoxygenase pathway (mainly C6-aldehydes) and of glucosinolate hydrolysis (mainly isothiocyanates), and their dynamics of formation after tissue disruption was given. Odor-active compounds of leaves were characterized by GC-Olfactometry (GC-O) and Aroma Extract Dilution Analysis (AEDA): volatile isolates obtained by HS-SPME from an aqueous extract and by Stir-Bar Sorptive Extraction (SBSE) from an ethanolic extract were analyzed. The most potent odor-active compounds fully or tentatively identified were (Z)- and (E)-3-hexenal, (Z)-1,5-octadien-3-one, responsible for green olfactory notes, along with 4-mercaptobutyl and 4-(methylthio)butyl isothiocyanate, associated with typical rocket and radish aroma. Relatively high odor potency was observed for 1-octen-3-one, (E)-2-octenal and 1-penten-3-one.

Software Defined Doppler Radar as a Contactless Multipurpose Microwave Sensor for Vibrations Monitoring.

A vibration sensor based on the use of a Software-Defined Radio (SDR) platform is adopted in this work to provide a contactless and multipurpose solution for low-cost real-time vibrations monitoring. In order to test the vibration detection ability of the proposed non-contact method, a 1 GHz Doppler radar sensor is simulated and successfully assessed on targets at various distances, with various oscillation frequencies and amplitudes. Furthermore, an SDR Doppler platform is practically realized, and preliminary experimental validations on a device able to produce a harmonic motion are illustrated to prove the effectiveness of the proposed approach.

Effect of the use of anti-hail nets on codling moth (Cydia pomonella) and organoleptic quality of apple (cv. Braeburn) grown in Alto Adige Region (northern Italy).

BACKGROUND: The anti-hail nets are widely used to protect apple fruit against hailstorms and hail damage. They can have also beneficial effects against pests in apple orchards, in particular codling moth (Cydia pomonella). However, covering the trees with anti-hail nets can modify the orchard microclimate and reduce the interception of light, thus potentially causing negative consequences on the organoleptic quality of apple fruits. RESULTS: A consistent reduction of the percentage of apple fruits infested by codling moth was registered as a result of the use of anti-hail nets during two consecutive harvest years. Their use did not affect fruit maturity, but reduced the skin colour, sugar content, pulp total phenol content, volatile compound composition and sensory characteristics. However, the results were inconsistent over the two years apart for total phenols, formation of two volatile compounds (butyl and hexenyl acetate, the first being one of the main odorants in most apple cultivars), sensory attributes of 'flavour of lemon' and 'juiciness'. For these parameters, the fruits from plots where the trees were not covered showed higher values than those from plots where anti-hail nets were used. CONCLUSIONS: The use of anti-hail nets was effective in preventing the attack of codling moth to apple fruits, suggesting their use in organic management where conventional insecticides are prohibited. Under the conditions tested, anti-hail nets showed a negative effect on some of the quality characteristics measured on apple fruits, which could influence consumer acceptability.

Improvement of a headspace solid phase microextraction-gas chromatography/mass spectrometry method for the analysis of wheat bread volatile compounds.

An improved method based on headspace solid phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME/GC-MS) was proposed for the semi-quantitative determination of wheat bread volatile compounds isolated from both whole slice and crust samples. A DVB/CAR/PDMS fibre was used to extract volatiles from the headspace of a bread powdered sample dispersed in a sodium chloride (20%) aqueous solution and kept for 60min at 50°C under controlled stirring. Thirty-nine out of all the extracted volatiles were fully identified, whereas for 95 other volatiles a tentative identification was proposed, to give a complete as possible profile of wheat bread volatile compounds. The use of an array of ten structurally and physicochemically similar internal standards allowed to markedly improve method precision with respect to previous HS-SPME/GC-MS methods for bread volatiles. Good linearity of the method was verified for a selection of volatiles from several chemical groups by calibration with matrix-matched extraction solutions. This simple, rapid, precise and sensitive method could represent a valuable tool to obtain semi-quantitative information when investigating the influence of technological factors on volatiles formation in wheat bread and other bakery products.

Combined effects of reduced malaxation oxygen levels and storage time on extra-virgin olive oil volatiles investigated by a novel chemometric approach.

Combined effects of oxygen level reduction in the malaxation headspace and storage time up to 6 months on the volatile composition of a monovarietal extra-virgin olive oil (EVOO), obtained from cv. Carboncella olives, were investigated by applying a full factorial design approach (4 oxygen levels × 4 storage times) on EVOOs extracted on an industrial scale in two mills, equipped with "two-phase" and "three-phase" centrifugation systems, respectively. The outcoming data were analysed by the chemometric technique called ANOVA-simultaneous component analysis (ASCA). Both reduction of oxygen malaxation levels and storage time significantly affected the volatile profile of the extracted EVOOs. Reduction of oxygen malaxation levels hindered the formation of lipoxygenase derived volatiles (hexanal, 1-hexanol, (Z)-2-hexenal, (E)-2-hexen-1-ol, (Z)-2-penten-1-ol, 2,4-hexadienals), whereas prolonged storage times were associated with increased levels of autoxidation products (octane, hexanal, C10 hydrocarbons) and other compounds that could originate from exogenous microbial activity (1-octen-3-ol, 6-methyl-5-hepten-2-one, benzaldehyde, methyl salicylate).

Quantitation of tr-cinnamaldehyde, safrole and myristicin in cola-flavoured soft drinks to improve the assessment of their dietary exposure.

Quantitation of tr-cinnamaldehyde, safrole and myristicin was carried out in 70 samples of cola-flavoured soft drinks purchased in eight European countries with the purpose of assessing the variability in the levels of these substances. Results indicated a limited variability in the content of the three substances: the ratio between the 90th and the 10th percentile concentration amounted to 21, 6 and 13 for tr-cinnamaldehyde, safrole and myristicin, respectively. The uncertainty in the assessment of dietary exposure to these substances due to the variability of their level in cola-flavoured drinks was low. Based on these analytical data and on refined food consumption data, estimates of exposure to safrole associated to cola drink consumption, along with Margin of Exposure (MOE) values, were obtained. For high consumers of cola-flavoured soft drinks in certain age groups, within some European countries, MOE values lower than 10,000 resulted, MOE values of 10,000 or higher having been stated by the EFSA as a quantitative criterion to identify low concern from a public health point of view and low priority for risk management actions. The lowest MOE values, from 1900 to 3000, were observed for children and teen agers in the United Kingdom and Ireland.

Impact of different distribution scenarios and recommended storage conditions on flavor related quality attributes in ripening fresh tomatoes.

Tomato (Solanum lycopersicum) fruits of three cultivars picked at different ripening stages were subjected to conditions in the laboratory simulating both short and long distribution chains as occurring in commercial practice and to recommended storage conditions. At the end of the postharvest experiments, a flavor quality profile of fruits was obtained by chemical determination of volatile compounds, sugars, and organic acids, and physical measurement of texture properties. In two of the three cultivars, the overall profile and many of the individual quality attributes was significantly affected by the distribution chain conditions, the effect being more pronounced in tomatoes marketed at full ripeness than in those marketed at an intermediate ripening stage. In these cultivars, tomatoes harvested at the Breaker stage, subjected to long chain conditions and then allowed to achieve full ripeness at room temperature, did not develop the same overall profile observed on fruits fully ripened on the vine and exposed to a simulated short chain. Fruits subjected to recommended commercial storage conditions, cold stored above the chilling range (10 or 13 °C) and at high relative humidity (95%), developed a different profile when compared to fruit exposed to the simulated long distribution chain (6 °C and 55-80% RH), suggesting that these changes in temperature and relative humidity may remarkably affect flavor formation in tomato fruits. Major drivers of profile differentiation between tomatoes subjected to different postharvest scenarios were the levels of some aroma compounds derived from aminoacids (1-nitro-2-phenylethane, 2-isobutylthiazole, phenylacetaldehyde, 2-phenylethanol, and 2- and 3-methylbutanal) and lipids ((E,E)- and (E,Z)-2,4-decadienal), and, among nonvolatile flavor compounds, of organic acids (citric and malic).

Multi-method comparison of carrot quality from a conventional and three organic cropping systems with increasing levels of nutrient recycling.

BACKGROUND: There is a need to advance the study of the effects of organic and conventional systems on product quality. In particular, little is known about the importance of different farming practices concerning nutrient cycling and the use of external inputs within organic farming for the quality characteristics of the products. In this study the quality characteristics of carrot grown under different farming practices (conventional and three organic cropping systems) over a two-year period were analysed with the aim of discriminating between organic and conventional and investigating the effect of different organic farming practices concerning nutrient recycling and use of external nutrient input. RESULTS: All quality characteristics measured did not give a clear differentiation between the carrots from the different growing systems, even when multivariate statistical evaluation (principal component analysis) was applied, because of the significance of the differences between the field replicates within each management system and of the seasonality. Only some tendencies were emphasised over the two years that could be related to the fertilisation practices and the external inputs used. CONCLUSION: The results indicated that it was not possible to discriminate over the years between carrots from conventional and different organic cropping systems even though controlled conditions and a multi-method approach of analysis were adopted.

Quantification of estragole in fennel herbal teas: implications on the assessment of dietary exposure to estragole.

Quantification of estragole content in commercial fennel herbal teas was carried out in order to allow for a more accurate estimate of the dietary exposure to estragole. A simple and rapid analytical method, based on Stir Bar Sorptive Extraction and GC-MS, was developed for this purpose. Fennel teas obtained from different types of commercial products were analysed. Concentration levels ranged from 241 to 2058 µg L(-1) in teas from teabags, from 9 to 912 µg L(-1) in diluted instant teas, from 251 to 1718 µg L(-1) in teas from not packaged seeds. Based on these data and considering the daily consumption of three portions of herbal tea, a maximum exposure to estragole for adults of 10 µg/kg bw/day was calculated. The relatively high level observed in diluted instant teas of some brands deserves attention since these products are designed for infant consumption. Estimated exposure in infants was up to 51 µg/kg bw/day for teas from teabags, and up to 23 µg/kg bw/day for instant teas. A generalization of the use of suitable technologies in production processes of instant teas could substantially reduce the exposure to estragole in the vulnerable population groups (infants, young children, pregnant and breastfeeding women) who consume these products.

Impact of innovative controlled atmosphere storage technologies and postharvest treatments on volatile compound production in cv. Pinova apples.

Organically grown apples cv. Pinova harvested at two different dates were stored at 1.3 degrees C for up to 4 months in air, up to 7 months in ULO (1.5 kPa of O(2) and 1.3 kPa of CO(2)) and in dynamic controlled atmosphere (DCA) conditions (0.4-0.6 kPa of O(2) and 0.6-0.8 kPa of CO(2)); the DCA storage method involved the use of a chlorophyll fluorescence monitoring system in order to detect low-O(2) stress in apples and to allow for the dynamic adaptation of storage atmosphere to O(2) levels that were lower than in ULO but still tolerated by fruits. A postharvest 1-MCP treatment (for 24 h at 1.3 degrees C) and a hot water treatment (for 180 s at 50 degrees C) were also tested on apples stored afterward in ULO and air, respectively. Volatile compounds isolated from the pulp of fruits were measured after 4 and 7 months, just upon removal from storage and after 11 days at 22 degrees C. Total amount of aroma compounds detected in apples stored in DCA was markedly higher (from 2- to 4-fold) than in fruits exposed to 1-MCP + ULO but, at most sampling times, significantly lower than in ULO fruits. Moderate differences in storage atmosphere composition between ULO and DCA significantly affected both total amount and profile of volatile esters. Analogous effects were observed on the alcohol precursors of the main esters. Exposure to 1-MCP inhibited biosynthesis of straight-chain esters more than that of branched-chain esters. The hot water treatment did not seem to produce marked changes in volatile composition after four months of air storage, except for a sharp accumulation of aldehydes during the shelf-life time. DCA storage technology, besides avoiding any chemical treatment, can preserve apple aroma compounds better than 1-MCP + ULO during long-term storage.

Nutritional value of cherry tomatoes (Lycopersicon esculentum Cv. Naomi F1) harvested at different ripening stages.

The average content of some classes of antioxidants is generally higher in cherry tomatoes than in normal-sized berries. The aim of this work was to assess the nutritional value of cherry tomato (cv. Naomi F1) by investigating the compositional pattern of berries harvested at different ripening stages and evaluating, in particular, all of the main antioxidants (carotenoids, ascorbic acid, phenolic compounds, and alpha-tocopherol) and the antioxidant activity of the water-soluble and water-insoluble fractions. Results confirmed the relatively high level of carotenoids in cherry tomato but showed that not all biologically active compounds necessarily increase in tomatoes picked at later stages of ripeness. Cherry tomatoes harvested at full ripeness exhibited the highest level of carotenoids and antioxidant activity in the water-insoluble fraction. On the other hand, no significant differences in ascorbic acid content were observed at different ripening stages, whereas the main phenolics content and the antioxidant activity of water-soluble fraction showed slight, but significant, decreases at later stages of ripeness.