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This work investigated the effect of gelatinization on the sensory traits of common (Fagopyrum esculentum) and Tartary (Fagopyrum tataricum) buckwheat flours in relation to their phenolic composition. Flours from two samples of common and Tartary buckwheat were heat-treated in the laboratory under controlled conditions to promote starch gelatinization; in addition, a common buckwheat sample heat-treated industrially was considered. The aromatic profiles of buckwheat samples were evaluated by electronic nose, while the electronic tongue was applied to assess taste. Rutin and quercetin concentrations were evaluated by HPLC; total phenolic compounds and antioxidant activity were also determined before and after thermal treatment. The heat treatment carried out in laboratory decreased both the total phenolic content and antioxidant activity and promoted the almost total hydrolysis of rutin into quercetin. The same effect was not detected in the sample treated industrially. Concerning sensory traits, a decrease in bitterness and astringency and a less intense aromatic profile were observed after gelatinization at lab scale; on the contrary, the industrially gelatinized sample was less affected by the thermal treatment, showing a sensory profile similar to the raw sample. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the applicability of e-senses (electronic nose, electronic tongue and electronic eye) for the characterization of edible olive oils (extra virgin, olive and pomace) and for the assessment of extra virgin olive oil and olive oil quality decay during storage at different temperatures. In order to obtain a complete description of oil samples, physico-chemical analyses on quality and nutritional parameters were also performed. Data were processed by PCA and a targeted data processing flow-sheet has been applied to physico-chemical and e-senses dataset starting from data pre-processing introducing an innovative normalization method, called t0 centering. On e-senses data a powerful mid-level data fusion approach has been employed to extract relevant information from different analytical sources combining their individual contributions. On physico-chemical data, an alternative approach for grouping extra virgin olive oil and olive oil samples on the basis of their freshness was applied and two classes were identified: fresh and oxidized. A k-NN classification rule was developed to test the performance of e-senses to classify samples in the two classes of freshness and the average value of correctly classified samples was 94%. Results demonstrated that the combined application of e-senses and the innovative data processing strategy allows to characterize edible olive oils of different categories on the basis of their sensorial properties and also to follow the evolution during storage of extra-virgin olive oil and olive oil sensorial properties thus assessing the quality decay of oils. [ABSTRACT FROM AUTHOR]

In recent decades, there has been a substantial increase in the consumption of fruits and vegetables due to their nutritional properties since they are known as sources of vitamins, minerals, fiber, and antioxidants. Moreover, a substantial growth in fresh-cut fruits and vegetables has been noticed because of their ease to use; in fact changes in human life styles have led consumers to move towards ready-to-eat products. In this context, product quality must be preserved at each step of product handling, processing, and storage, and therefore rapid methods should be available to provide useful information in process management. In this review an overview of the applications of widely used non-destructive techniques, namely, electronic nose and visible/near infrared spectroscopy, for measuring quality of fruits and vegetables is presented. A brief description of spectroscopic and electronic devices and a selection of applications are provided. Future perspectives about the simplification/application of these non-destructive techniques are finally explored. [ABSTRACT FROM AUTHOR]

Electronic senses were applied in order to evaluate the effect of brewing temperature on the sensorial properties of espresso coffees (ECs) produced by a bar machine of the latest generation able to work with constant, increasing and decreasing water temperature profiles. The obtained ECs were analyzed by e-nose, e-tongue and e-eye to depict their aroma and taste fingerprint and to evaluate the visual characteristics of foam. Physicochemical analyses were carried out to determine the extraction rate of typical EC components and to evaluate their antioxidant activity. The electronic devices coupled with multivariate statistical analysis demonstrated a good ability to discriminate and characterize coffee samples on the basis of their sensorial properties in relation to the brewing temperature. According to these results, electronic senses can be applied to assess the influence of the percolation parameters on the sensory attributes of ECs, thus resulting useful tools for the optimization of processing conditions. [ABSTRACT FROM AUTHOR]

Lupin seeds are rich in proteins, lipids and bioactive compounds, but before consumption must be debittered to remove toxic alkaloids. Traditionally, debittering is a water-intensive and protracted process, lasting up to six days. To develop a more efficient procedure, different washing solutions (0.5% and 1% NaCl or citric acid), with or without the use of ultrasound, were applied on Lupinus albus seeds and compared to two control methods, the first with water and the second with a sodium chloride solution. The sonication did not accelerate debittering, while the sodium chloride and citric acid solutions significantly shortened debittering time, reduced water consumption and decreased alkaloid content to commercial values (0.31–1.03 g/kg dry matter). Debittering with a 1% citric acid solution saved 88 h and 65 L water/kg dry lupin compared to the water control method, and 13 h and 31 L water/kg dry lupin compared to the salt solution control method. The electronic tongue grouped the experimental and commercial samples in well-defined clusters; bitter and umami tastes were the main factors, well correlated with alkaloid content. The proposed procedure, either with citric acid or sodium chloride, could be easily adopted by the industry to reduce time and costs of lupin debittering. [Display omitted] • Different debittering solutions of NaCl or citric acid were tested on Lupinus albus. • Low frequency ultrasound effect was assessed, but did not improved debittering. • The citric acid solutions shortened debittering time and reduced water consumption. • The e-tongue found that bitter and umami sensors were correlated to alkaloid content. [ABSTRACT FROM AUTHOR]

The aim of this work was to follow the evolution of physicochemical (dry matter, NaCl concentration, pH, water activity), morphological (image analysis) and aromatic (e-nose) characteristics of the three main Italian PDOs during processing, from slaughtering to end of ripening. Main phenomena distinguishing the PDOs are NaCl concentration increase, which is higher in Toscano than in Parma and San Daniele hams, starting from the salting phase. Water activity values decrease during processing, and the lowest values are detected in Toscano ham. Changes in morphological parameters (area, shape) and in color progressively occur during processing and are more pronounced in Toscano ham. A clear evolution of aroma of the three PDOs has been observed by e-nose, and the complexity of the aromatic profile of the ripened hams is clearly highlighted. [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this study is to investigate the feasibility of a 'holistic' approach, using near infrared ( NIR) spectroscopy and electronic devices (electronic nose and electronic tongue), as instrumental tools for the classification of different coffee varieties. Analyses were performed on green coffee, on ground roasted coffee and on coffee beverage. Principal component analysis was applied on spectral and sensory data to uncover correlations between samples and variables. After variable selection, linear discriminant analysis was used to classify the samples on the basis of the three coffee classes: Robusta, natural Arabica and washed Arabica. RESULTS Linear discriminant analysis demonstrates the practicability of this approach: the external test set validation performed with NIR data showed 100% of correctly classified samples. Moreover, a satisfying percentage of correct classification in cross-validation was obtained for the electronic devices: the average values of correctly classified samples were 81.83% and 78.76% for electronic nose and electronic tongue, respectively. CONCLUSION NIR spectroscopy was shown to be a very reliable and useful tool to classify coffee samples in a fast, clean and inexpensive way compared to classical analysis, while the electronic devices could assume the role of investigating techniques to depict the aroma and taste of coffee samples. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: This study aimed at characterizing the sensory quality of Italian PDO dry-cured Parma, San Daniele and Toscano hams, applying a multi-disciplinary approach. Ham sensory profile as well as physico-chemical, aromatic, morphological and textural characteristics was investigated. There was a great difference between Toscano ham and Parma and San Daniele hams, which were more similar even though differentiated. Toscano ham showed higher scores for pork-meat odor, saltiness, dryness, fibrousness and hardness; accordingly, this ham was described by a high NaCl content and by high values of instrumental hardness, cohesiveness, gumminess and chewiness. Parma ham was characterized by a cured flavor, whereas San Daniele ham showed a wider fatty area and higher pH values. Parma and San Daniele hams were also described by higher values of sweetness, RGB color values and water activity. Sensory characteristics evaluated by trained assessors were correlated to instrumental measures, indicating that instrumental devices can be effectively applied for dry-cured ham characterization. [Copyright &y& Elsevier]

Abstract: Four varieties of cultivated blueberries (Vaccinium corymbosum) and a wild crop (Vaccinium miyrtillus) originating form the Modena region in Italy (Mirtillo nero dell’Appennino Modenese) and protected by the mark of origin, were examined in order to determine their antioxidant activity as related to their phenolic composition. The antioxidant activity was measured as radical scavenging activity, ferric reducing activity, and by an amperometric method; the total phenolics and total anthocyanins were determined by colorimetric methods; individual anthocyanins were evaluated by HPLC. Results showed that total phenolics and total anthocyanin concentrations were, respectively two fold and three fold higher in the wild fruits, which also had a higher anthocyanin-to-total phenolic ratio. Determination of individual anthocyanins put in evidence some differences between the cultivated and wild varieties, in particular the absence of acylated anthocyanins in wild blueberries. The antioxidant activity was much higher in wild blueberries than in the cultivated ones, and it was more related to the total phenolic rather that to the anthocyanin concentration. [Copyright &y& Elsevier]

Abstract: A glassy carbon electrode coated with cobalt oxide/multi-wall carbon nanotubes (MWCNT) system was used for the detection of carbohydrates and thiols. The modification of the glassy carbon electrode increased the anodic current response of these organic compounds and decreased their overvoltage. The amperometric responses were extremely stable with no loss of sensitivity over many days of storage. Such attractive performance characteristics indicate great promise for using this new catalytic system for monitoring in fast and simple way compounds of great interest for food industry, biotechnology and clinical diagnostics. [Copyright &y& Elsevier]

Abstract: A disposable, small scale and low-cost electrochemical “wall-jet” flow-cell was build up together with a graphite lead mounted onto a pencil holder able to modulate the current response by the control of the surface area of the electrode. The total phenolic content of different types of tea infusions was determined and compared with the conventional Folin–Ciocolteau method. An index of antioxidant power was also proposed and data were compared with those obtained by the DPPH* assay. [Copyright &y& Elsevier]

Abstract: A commercial electronic nose (PEN 2, Win Muster Airsense) was used to classify four peach cultivars and to assess the ripening stage during shelf-life. Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to investigate whether the electronic nose was able to distinguish among four diverse cultivars. PCA applied on the electronic nose data, collected during shelf-life from harvest until senescence, highlighted the ability of the instrument to assess the ripening stage of peaches. The loading analysis identified one sensor as the only relevant one in the discrimination of peaches on the basis of their shelf-life. The responses of the sensor were plotted against time and fitted with a sigmoid transition function allowing the definition of three different ripening stages (unripe, ripe, over-ripe) based on the trend of first and second time derivatives. Classification and regression tree (CART) analysis was applied to characterise peach samples into the three classes. The performance of the electronic nose was compared with the results of classical and non-destructive techniques such as ethylene measurement and colour evaluation, frequently used to assess the ripening stage of climacteric fruit. [Copyright &y& Elsevier]

Evaluating the possibility of extending shelf life of rice germ (a by-product of rice milling process) by reducing water activity in combination with storage atmosphere packaging, without any heat treatment, is the aim of the present study. Samples at different water activities (0.55, 0.45 and 0.36) were packed in air, argon or under vacuum, and stored at 27 °C for 150 days. To the aim, a non-targeted approach was applied by means of an FT-NIR spectrometer in reflectance with a rotating sample holder and a portable electronic nose, equipped with 10 non-specific sensors. For understanding the impact of the factors under study on the rice germ shelf life, a modified mid-level data fusion approach was applied to enhance the information most correlated with time. Moreover, Principal Component Analysis was applied on fused data to follow samples evolution during storage and identify different clusters according to the storage conditions. The rice germ case study allowed to better understand the information captured by the non-specific sensors: a 2D correlation map was developed combining the e-nose data with the NIR spectral information, highlighting relationships among NIR absorption bands and classes of chemical compounds inducing e-nose responses. A data fusion approach highlighted the importance of water activity on rice germ storage, while no interesting differences were ascribable to storage atmosphere packaging systems. In terms of correlation, the sensors could be divided in two groups, negatively inter-correlated: sensors ascribable to aromatic compounds (WC) and correlated with the NIR band around 4800–4900 cm−1 (N–H bending of primary amides, typical for peptides coming from protein hydrolysis); broad-range response sensors (WS), linked with the NIR band at 5128 cm−1 (second overtone of C O stretching of esters). Image 1 • Rice germ storage is studied by a combination of innovative non-targeted approaches. • A tailor-made data centering (t0 centering) is proposed to enhance time trend. • A novel data fusion strategy merges and correlates MOS-sensors and FT-NIR signals. • PCA on fused data highlights the importance of water activity in rice germ storage. • Correlation map with FT-NIR data ascribes chemical meaning to non-specific sensors. [ABSTRACT FROM AUTHOR]

Propranolol (PPN) is widely used in children to treat various cardiovascular diseases. The availability of a suitable PPN solution should avoid recourse to extemporaneous preparations of unknown/limited stability, as commonly made in hospital pharmacies. However, the development of pediatric PPN solutions is hindered by their instability to light and stability at pH ≈ 3, bitter taste, and the need to improve palatability and avoid co-solvents, flavoring agents, or preservatives that are potentially toxic. In this study, cyclodextrin (CD) complexation has been exploited to develop a safe, stable, and palatable oral pediatric solution of PPN. An initial screening among various CDs allowed us to select HPβCD for its good complexing ability and no toxicity. Drug-HPβCD physical mixtures or co-ground systems (1:1 or 1:2 mol:mol) were used to prepare 0.2% w/v drug solutions. Photo stability studies evidenced the protective effect of HPβCD, revealing a reduction of up to 75% in the drug degradation rate after 1 h of exposure to UV radiation. Storage stability studies showed unchanged physical–chemical properties and almost constant drug concentration after 6 months and under accelerated conditions (40 °C), despite the less aggressive pH (≈5.5) of the solution. The electronic tongue test proved that the HPβCD taste-masking properties improved the formulation palatability, with a 30% reduction in drug bitterness. [ABSTRACT FROM AUTHOR]

The potentials of Fourier transform (FT) near- (NIR) and mid-infrared (IR) spectroscopy, and electronic nose (e-nose) on varietal classification of Turkish olive oils were demonstrated. A total of 63 samples were analyzed, comprising Ayvalik, Memecik, and Erkence oils. Spectra were pretreated with standard normal variate and second derivative. Classification models were built with orthogonal partial least square-discriminant analysis (OPLS-DA), considering the single data sets and also the combined FT-NIR-IR spectra. OPLS-DA models were validated both by cross validation and external prediction. All the models gave good results, being the average correct classification percentages in prediction higher than 90% for spectroscopic data and equal to 82% for e-nose data. The combined FT-NIR-IR data set gave the best results in terms of coefficients of determination (0.95 and 0.67). Different e-nose sensors discriminated Ayvalik, Memecik, and Erkence oils, explaining their distinct aromatic profiles. [ABSTRACT FROM AUTHOR]

Postharvest life of raspberries ( Rubus idaeus L.) is limited due to their high respiration rate, loss of firmness and freshness and susceptibility to fruit rot. The aim of this research was to evaluate the effects of various packaging solutions on physico-chemical, nutritional and aromatic properties of raspberries during storage at +4 °C up to 7 days. Plastic materials with low (LDPE) and high (LDPE/EVOH/LDPE) gas barrier, a biopolymeric film (PLA) with medium gas barrier and micro perforated stretch film (PVC) were used. The packaging material modified the composition of the atmosphere in the package, which depended on the combined action of the respiration activity of the fruit and the permeability of the material. Results showed that the most sensitive parameters for the assessment of raspberry decay were percentage of damaged berries, weight loss, fruit softening and the aromatic profile development, evaluated by an electronic nose; these parameters showed significant changes during storage and were influenced by the packing material. All samples showed a clear loss of firmness after 4 days of storage, which was maximally reduced in the case of LDPE/EVOH/LDPE and PLA packages. Raspberries stored in PVC packaging material had an aromatic development similar to the control, whereas berries stored in the medium and high barrier materials showed important changes in the aromatic profile, reflecting anaerobic metabolism of fruit. Soluble solids, pH, total phenolics and ascorbic acid did not change significantly; changes in colour and total anthocyanins were observed, with differences depending on the kind of packaging. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to investigate the applicability of non-destructive techniques in monitoring freshness decay of fresh-cut Valerianella locusta L. during storage at different temperature. The sampling was performed for 15 days for Valerianella samples preserved at 4 and 10°C, and for 7 days for samples stored at 20°C. The quality decay of samples was evaluated by quality parameters (pH, water content, total phenols, chlorophyll a fluorescence) and by non-destructive systems (electronic nose and visible–near infrared spectroscopy). Cluster Analysis (CA) was performed on quality indices and four clusters were identified, namely “fresh”, “acceptable”, “spoiled” and “very spoiled”. Principal Component Analysis (PCA) was applied on the electronic nose data in order to evaluate the feasibility of this technique as a rapid and non-destructive approach for monitoring the freshness of fresh-cut Valerianella during storage. Linear Discriminant Analysis (LDA) and PLS-discriminant analysis (PLS-DA) models were developed to test the performance of electronic nose and VIS–NIR, respectively, to classify samples in the four classes of freshness. The average value of samples correctly classified using LDA was 95.5% and the cross validation error rate was equal to 8.7%. The results obtained from PLS-DA models, in validation, gave a positive predictive value (PPV) of classification between 74% and 96%. Finally, predictive models were performed using Partial Least Squares (PLS) regression analysis between quality indices and VIS–NIR data. RPD values <3 were obtained for water content and pH. Excellent results were obtained for total phenols with R cv 2 and RPD equal to 0.89 and 3.19, and for chlorophyll a fluorescence with Rcv 2 and RPD equal to 0.92 and 3.22, respectively. Results demonstrated that electronic nose and VIS–NIR are complementary techniques able to support the conventional techniques in the shelf-life assessment of fresh-cut V. locusta L. providing information useful for a better management of the product along the distribution chain. [Copyright &y& Elsevier]

This study aimed at addressing the effect of quinoa sprouting on saponins which are considered the main responsible for quinoa bitterness and astringency, and consequently on quinoa taste. Whole quinoa was sprouted for 12, 24, 48, and 72 h at 22 °C and dried at 55 °C for 6 h. Quinoa taste was assessed by electronic tongue and mainly related to the amount of saponins that were evaluated by thin layer chromatography (TLC) and mass spectrometry (MS). Sprouting decreased quinoa bitterness and astringency, with the main changes occurring within the 48 h of treatment. Both semi-quantitative (by TLC) and quantitative (by MS) analysis revealed that changes in quinoa taste upon sprouting was mainly related to the decrease in the amount of saponins, reaching the value of 0.086 mg/100 g after 48 h of treatment. Finally, changes in phenolic compounds seem to play a minor role in affecting the taste traits of sprouted quinoa. • Whole quinoa was sprouted up to 72 h at 22 °C. • Sprouting increased quinoa sourness. • Sprouted quinoa was perceived less bitter and astringent after 48 h of sprouting. • Saponin content decreased upon sprouting. [ABSTRACT FROM AUTHOR]

The impact of 48 h sprouted quinoa (SQ) was assessed in bread-making. Wheat flour (WF) was replaced with SQ at different levels (i.e., 10:90, 20:80 and 30:70, SQ:WF ratio). Once the optimal replacement level of SQ was identified, the bread-making performance of this ingredient was compared with those of pearled quinoa (PQ), commonly used in bread-making. Starch pasting properties and gluten aggregation behavior were not strongly affected at 20:80 level. Regardless the replacement level, SQ caused an increase in dough water absorption and in softening degree, and a decrease in stability, suggesting weakening of the gluten network. During leavening, SQ improved dough development and gas production, due to increased sugar content (i.e. maltose, sucrose and D-glucose). The best bread-making performance (highest bread specific volume and lowest crumb firmness) was obtained at 20:80 replacement level. Compared to PQ, SQ exhibited the best leavening capacity (high dough development, gas production and gas retention) and bread properties (high specific volume and low crumb firmness), likely due to its higher sugar content. Moreover, 20SQ bread was characterized by a decreased bitterness assessed by electronic-tongue. In conclusion, sprouting might be considered a valid alternative to pearling to improve the characteristics of quinoa enriched bread Image 1 • Enrichment of wheat bread with sprouted quinoa. • Using sprouted quinoa improved dough leavening properties and bread features. • Using 20% sprouted quinoa led to the highest bread volume. • Sprouting has to be preferred to pearling in quinoa bread-making. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The consumption of mulberry leaf tea is popularly increasing worldwide due to its potential health benefit associated with phenolic compounds. To ensure the quality, the content of phenolic compounds of mulberry leaf tea need to be monitored throughout the storage period. OBJECTIVE: This research proposed a rapid prediction of phenolic compounds and antioxidant activity of mulberry leaf tea using an electronic tongue (e-tongue). METHODS: Total phenolic content (TPC), total flavonoids content (TFC) and antioxidant activity (FRAP and DPPH) of mulberry leaf tea stored at 30–60°C for 12 months were measured by an e-tongue and conventional chemical analyses. Partial least squares (PLS) regression was applied to predict chemicals parameters by e-tongue data. RESULTS: The PLS models for TPC, TFC, FRAP, and DPPH achieved good predictability with high values of coefficient of determination (R p 2 = 0.956, 0.964, 0.926, and 0.943, respectively) and gave low mean square error of prediction. CONCLUSION: The results demonstrated that e-tongue can be applied as a rapid and non-destructive tool for the simultaneous evaluation of phenolics compounds and antioxidant activity to ensure the quality and health benefits of mulberry leaf tea. [ABSTRACT FROM AUTHOR]

The evaluation of meat and fish quality is crucial to ensure that products are safe and meet the consumers’ expectation. The present work aims at developing a new low-cost, portable, and simplified electronic nose system, named Mastersense, to assess meat and fish freshness. Four metal oxide semiconductor sensors were selected by principal component analysis and were inserted in an “ad hoc” designed measuring chamber. The Mastersense system was used to test beef and poultry slices, and plaice and salmon fillets during their shelf life at 4 °C, from the day of packaging and beyond the expiration date. The same samples were tested for Total Viable Count, and the microbial results were used to define freshness classes to develop classification models by the K-Nearest Neighbours’ algorithm and Partial Least Square–Discriminant Analysis. All the obtained models gave global sensitivity and specificity with prediction higher than 83.3% and 84.0%, respectively. Moreover, a McNemar’s test was performed to compare the prediction ability of the two classification algorithms, which resulted in comparable values (p > 0.05). Thus, the Mastersense prototype implemented with the K-Nearest Neighbours’ model is considered the most convenient strategy to assess meat and fish freshness. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the potential compositional differences among different populations of H. officinalis subsp. aristatus (Godr.) Nyman. The plant specimens were collected in different locations in Western Balkans (Kosovo and Albania) and subjected to phytochemical profiling (GC-MS for their essential oils and HPLC-UV-DAD for fingerprinting of their solvent extractable phytochemicals). Antioxidant capacity, total flavonoid and phenol contents were measured using different assays. Out of the five location considered, the specimen from one location displayed significant differences both in terms of essential oil composition and of polyphenolic total content. The electronic nose measurements used to characterize their aromatic profile, was able to clearly discriminate the accessions, indicating a good correlation, in particular, with the marked chemotypic difference established by essential oil profiling (1,8-cineol vs. isopinocamphone/camphone). H. officinalis subspp. aristatus (Godr.) Nyman may constitute an interesting subject for further studies on the effect of genetic and environmental factors, or of their combinations, on its chemotypic expression and sensorial properties. [ABSTRACT FROM AUTHOR]

The consumption of whole-grain food-including pasta-has been increasing steadily. In the case of whole-grain pasta, given the many different producers, it seems important to have some objective parameters to define its overall quality. In this study, commercial whole-grain pasta samples representative of the Italian market have been characterized from both molecular and electronic-senses (electronic nose and electronic tongue) standpoint in order to provide a survey of the properties of different commercial samples. Only 1 pasta product showed very low levels of heat damage markers (furosine and pyrraline), suggesting that this sample underwent to low temperature dry treatment. In all samples, the furosine content was directly correlated to protein structural indices, since protein structure compactness increased with increasing levels of heat damage markers. Electronic senses were able to discriminate among pasta samples according to the intensity of heat treatment during the drying step. Pasta sample with low furosine content was discriminated by umami taste and by sensors responding to aliphatic and inorganic compounds. Data obtained with this multidisciplinary approach are meant to provide hints for identifying useful indices for pasta quality. Practical Application As observed for semolina pasta, objective parameters based on heat-damage were best suited to define the overall quality of wholegrain pasta, almost independently of compositional differences among commercial samples. Drying treatments of different intensity also had an impact on instrumental sensory traits that may provide a reliable alternative to analytical determination of chemical markers of heat damage in all cases where there is a need for avoiding time-consuming procedures. [ABSTRACT FROM AUTHOR]

The aim of this work was to provide a thorough evaluation of quality characteristics of French fries prepared from frozen potatoes using different home-cooking systems. French fries were prepared using deep-fat fryer, air-frying appliances, convection oven, and microwave oven. Two commercial frozen potato sticks, specifically intended for deep-fat frying and for oven cooking, respectively, were used for the cooking tests. The obtained French fries were analyzed for compositional parameters and for sensory properties by instrumental analyses (texture, color, and aroma) and descriptive analysis. Significant differences in physico-chemical and nutritional characteristics of the final products were observed, depending on both the raw material and the cooking system; analytical data were in good agreement with the sensory results. French fries obtained by oven cooking of apposite frozen potato sticks had sensory characteristics similar to those of deep-fat fried potatoes, with low acrylamide (about 50 µg/kg) and lower fat content (7.4-11.1 g/100 g compared to 14.5-17.1 g/100 g in deep-fat fried potatoes); on the other hand, oven cooking was the most expensive system in terms of energy consumption. Quality characteristics of French fries obtained by air-frying and microwave cooking were poorer, and these products had higher acrylamide content (up to 410 µg/kg in microwave cooked samples). [ABSTRACT FROM AUTHOR]

Highlights: [•] The evolution of spectra of fresh-cut Valerianella during shelf-life was studied. [•] PLS-RCA technique was applied to spectra for the selection of the relevant variables. [•] Four effective wavelengths were selected: 520nm, 680nm, 710nm and 720nm. [•] MLR was applied in order to verify the effectiveness of the selected wavelengths. [•] A simple, handheld optical device implementing the four wavelengths is depicted. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the type of sugar in the osmotic solution and of the time of processing on the volatile compounds of strawberries was studied, in order to optimize the technique as a pre-treatment to further processing. Strawberries of cultivar ‘Camarosa’, cut into 1cm thick slices, were subjected to osmotic dehydration at 30°C for 1, 2, 4 and 6h using either 60% (w/w) sucrose or 60% (w/w) sorbitol solutions. Volatile compounds of fresh and processed strawberry slices were analyzed by static headspace—gas chromatography. Osmotic treatments provoked a loss in volatile compounds due to the migration, mainly of esters, into the osmotic media. The variations in the volatile pattern depended on both time of treatment and type of osmotic solution. The greater changes occurred after 2h in sucrose; with a promotion of fermentative volatiles (acetaldehyde, ethyl acetate), and a decrease in the other volatiles. Using sorbitol as osmotic agent, the major variations in the volatile pattern occurred after 4h of osmosis, and the fermentative process was less important than in sucrose, as sorbitol could be less effective in forming a peripheral layer at the fruit surface and/in reducing tissue porosity. [Copyright &y& Elsevier]

Abstract: FT-NIR spectroscopy and an electronic nose were used to evaluate the Optimal Cooking Time for milled, parboiled and quick-cooking rice and compared with gelatinization time and the suggested cooking time reported on package labels. Rice spectral data collected in reflectance mode using an FT-NIR spectrometer were transformed into second derivative for chemometric analysis. This technique detected the modifications induced by the hydration process during cooking and related to specific molecular groups. A electronic nose/commercial, consisting of metal oxide semiconductor and metal oxide semiconductor field effect transistor sensors, was used to follow the evolution of rice aromas during cooking. The results obtained by the techniques confirmed the feasibility of both methods to follow the rice profile during cooking and to evaluate the optimal cooking time, rapidly and objectively. [Copyright &y& Elsevier]

Abstract: Classification and influence matrix analysis (CAIMAN) is a new classification method, recently proposed and based on the influence matrix (also called leverage matrix). Depending on the purposes of the classification analysis, CAIMAN can be used in three outlines: (1) D-CAIMAN is a discriminant classification method, (2) M-CAIMAN is a class modelling method allowing a sample to be classified, not classified at all, or assigned to more than one class (confused) and (3) A-CAIMAN deals with the asymmetric case, where only a reference class needs to be modelled. In this work, the geographic classification of samples of wine and olive oil has been carried out by means of CAIMAN and its results compared with discriminant analysis, by focusing great attention on the model predictive capabilities. The geographic characterization has been carried out on three different datasets: extra virgin olive oils produced in a small area, with a “protected denomination of origin” label, wines with different denominations of origin, but produced in enclosed geographical areas, and olive oils belonging to different production areas. Final results seem to indicate that the application of CAIMAN to the geographical origin identification offers several advantages: first, it shows – on an average basis – good performances; second, it is able to deal in a simple way classification problems related to tipicity, authenticity, and uniqueness characterization, which are of increasing interest in food quality issues. [Copyright &y& Elsevier]

Background: Diagnostic methods for the early identification of ovarian cancer (OC) represent an unmet clinical need, as no reliable diagnostic tools are available. Here, we tested the feasibility of electronic nose (e-nose), composed of ten metal oxide semiconductor (MOS) sensors, as a diagnostic tool for OC detection. Methods: Women with suspected ovarian masses and healthy subjects had volatile organic compounds analysis of the exhaled breath using e-nose. Results: E-nose analysis was performed on breath samples collected from 251 women divided into three groups: 86 OC cases, 51 benign masses, and 114 controls. Data collected were analyzed by Principal Component Analysis (PCA) and K-Nearest Neighbors' algorithm (K-NN). A first 1-K-NN (cases vs. controls) model has been developed to discriminate between OC cases and controls; the model performance tested in the prediction gave 98% of sensitivity and 95% of specificity, when the strict class prediction was applied; a second 1-K-NN (cases vs. controls + benign) model was built by grouping the non-cancer groups (controls + benign), thus considering two classes, cases and controls + benign; the model performance in the prediction was of 89% for sensitivity and 86% for specificity when the strict class prediction was applied. Conclusions: Our preliminary results suggested the potential role of e-nose for the detection of OC. Further studies aiming to test the potential adoption of e-nose in the early diagnosis of OC are needed. [ABSTRACT FROM AUTHOR]