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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.

In the frame of reformulating food products for valorizing underutilized crops and enhancing both the nutritional and sensory characteristics of traditional foods, this study explored the potential impact of sprouting on some features of couscous prepared from buckwheat. Specifically, the impact of two sprouting times (48 h and 72 h) and two enrichment levels (25% and 50%) on physical properties (bulk density, hydration properties), cooking behavior (e.g., texture), chemical features (e.g., total phenolic content, rutin and quercetin), antioxidant activity (DPPH assay), and sensory traits (by means of electronic nose, tongue, and eye) was considered. Results showed that the replacement of 50% of pre-gelatinized buckwheat flour with 72 h-sprouted buckwheat flour resulted in a couscous with a higher content of phenolic compounds (including rutin and quercetin) and antioxidant activity; the related values further increased upon cooking. Moreover, except for the hardness and gumminess that were worsened (i.e., their values increased), cohesiveness and resilience improved in the presence of sprouted buckwheat (i.e., their values increased). Finally, the overall sensory traits improved with the addition of 50% sprouted buckwheat, since both bitterness and astringency decreased in the reformulated couscous. [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]

In recent years, increasing attention has been addressed to buckwheat, an interesting minor crop with an excellent nutritional profile that contributes to the sustainability and biodiversity of the agri-food system. However, the high content of rutin and quercitin present in this pseudocereal can elicit undesirable sensory properties, such as bitterness and astringency, that can limit its exploitation in food formulations. The aim of the present study was to characterize six gluten-free porridge-type formulations (called polenta) prepared using corn and buckwheat flour. Specifically, polenta samples were prepared adding common (CB) or Tartary buckwheat (TB) flour at 20% (CB20; TB20), 30% (CB30; TB30), and 40% (CB40; TB40) to corn flour. Product characterization included sensory and instrumental analyses (electronic tongue, colorimeter, and Texture Analyzer). Products containing Tartary buckwheat were darker, firmer, and characterized by a higher intensity of bitter taste and astringency than those prepared with common buckwheat. In this context, the impact of buckwheat species seems to be more important at 30% and 40% levels, suggesting that lower additions may mask the differences between the species. The gathered information could support the food industry in re-formulating products with buckwheat. Finally, findings about the relationship between instrumental and sensory data might be exploited by the food industry to decide/choose what indices to use to characterize new formulations and/or new products. [ABSTRACT FROM AUTHOR]

The aim was to evaluate the sensory quality by electronic nose (EN) and tongue (ET) of bread added by cobia minced protein in differents times of storage. Two samples were elaborated: (a) control (FF—traditional bread); (b) added by 10% Cobia minced protein (FPN). The two samples of bread were analyzed from time "zero" (1 hr after being baked) to time "five" (120 hr). A Portable EN (PEN2) composed of 10 sensors was used. Operating conditions: flow rate 300 ml/min, injection time 60 min, flush time 180 min. To ET (Taste‐Sensing System SA402B) 5 sensors were used. All samples were analyzed twice and the average was analyzed by Principal Component Analysis, showing the relationship among the samples and the variables. The greatest differences between the odors were observed after 120 hr of storage. In the first 48 h, the EN was unable to differentiate the samples. The biggest differences of taste were observed at t0. In the other evaluation times, the samples reduced their differences. The use of electronic sensory methods showed promising. Confer greater specificity in the determination of odors and taste of products. Therefore, these tools can be used to improve the sensory characteristics of the new products, as enriched foods. Practical Applications: Bread is a basic food of the world population, but it does not present a big quantity/quality protein content. Using fish protein concentrate in bread improves the nutritional quality of this product, however, in function of the physico‐chemical composition, fish and derivates may present a strong characteristic odor/taste, rejected by a large part of the population. The sensory characteristics of a product are determining factors for the choice and purchase by the consumers. Maintaining a permanent panel of trained evaluators takes high time and continuous costs, and is not entirely accurate. The use of technologies used by the electronic nose and tongue can assist in a greater standardization of food, especially when it involves the development of new products, ingredients, or differentiated raw ingredients, as made in this study. [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 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 development of innovative legume-enriched rice products is a promising way to exploit rice varieties with a low sensory grade. In this work, a multidisciplinary approach was applied to the characterization of extruded breakfast cereals prepared from African-grown Oryza glaberrima (cv. Viwonor) or Oryza saliva (cv. Jasmine 85) enriched with 30% cowpea flour, obtained from sprouted or nonsprouted cowpea. Regardless of the rice species, addition of sprouted cowpea flour conferred a peculiar volatiles profile, rich in sour, bitter, and astringent taste. Protein structural indices provided molecular insights about the macroscopic differences among samples. Extruded products from O. glaberrima were character-ized by lower expansion rates with respect to those obtained from O. saliva, regardless of the type of cowpea flour. Sprouting time had a positive influence on the hardness of extruded glaberrima-based products, facilitating formation of a more compact matrix, but it did not influence sativa-based products. Therefore, the breakdown of protein during sprouting appeared fundamental for the incorporation of legume proteins in more compact matrices, such as the one from saliva rice. In the glaberrima-based products, addition of sprouted cowpea resulted in further loosening of the structure, and this was more evident at increased sprouting times. [ABSTRACT FROM AUTHOR]

A simple sensing unit based on a disposable screen printed carbon electrode coated by an electrospun nylon-6 nanofibrous membrane was developed for in situ selective determination of ascorbic acid (AA) in different types of fruits. The membrane, prepared by electrospinning, represents a selective barrier to possible interferents, such as phenolic compounds, allowing an improved selectivity towards AA. No sample preparation and/or dilution is necessary since the new device is applied directly 'pricking' the fruit with the electrode. A good correlation was obtained between the amperometric in situ method and a reference chromatographic methodology (HPLC-UV) when applied to various fruit samples. [ABSTRACT FROM AUTHOR]

The paper describes a rapid and simple method for the evaluation of the antioxidant capacity in oil in water nanoemulsion. This procedure does not require extensive sample treatment and, most important, does not use any organic solvent for dissolution of the fatty matrix. The nanoemulsions were directly injected in a flow injection (FI) system with an electrochemical detector equipped with a glassy carbon working electrode operating amperometrically at a potential of +0.8 V (vs. Ag/AgCl). Results obtained were compared with those obtained by the Oxygen Radical Absorbance Capacity (ORAC) assay. [ABSTRACT FROM AUTHOR]

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]

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]

The performance of two innovative packaging materials was investigated on two Sardinian extra-virgin olive oils (Nera di Gonnos and Bosana). In particular, a transparent plastic film loaded with a UV-blocker (packaging B) and a metallized material (packaging C) were compared each other and to brown-amber glass (packaging A). During accelerated shelf-life tests at 40 and 60 °C, the evolution of quality parameters (i.e., acidity, peroxide value, K270, and phenolic content) was monitored, together with the aromatic fingerprint evaluated by electronic nose. Packaging B resulted in the best-performing material in protecting oil from oxidation, due to its lower oxygen transmission rate (0.1 ± 0.02 cm3/m2 24 h) compared to packaging C (0.23 ± 0.04 cm3/m2 24 h). At the end of storage, phenolic reduction was on average 25% for packaging B and 58% for packaging C, and the aromatic fingerprint was better preserved in packaging B. In addition, other factors such as the sanitary status of the olives at harvesting and the storage temperature were demonstrated to have a significant role in the shelf life of packaged extra-virgin olive oil. [ABSTRACT FROM AUTHOR]

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]

This study investigates the effects of three cooking methods (boiling, steaming and microwaving) on the nutritional and physical properties of cauliflowers, carrots and sweet potatoes; e-senses were applied to interpret the sensory characteristics according to physico-chemical aspects. The nutritional quality was evaluated by determining the concentrations of key components and the antioxidant activity; e-sense data, combined with texture parameters, were processed by a principal component analysis. The cooking method and time significantly influenced the quality of the three products. Boiling, which detrimentally affected ascorbic acid, total phenolic concentration and antioxidant activity, enhanced carotene accessibility. Steaming produced losses in ascorbic acid, increasing total phenolics and carotenoids. Microwaving resulted in minor changes in ascorbic acid concentrations, preserved carotenoids and increased total phenolics. The nutritional quality was better preserved or enhanced using shorter cooking times. The elaboration of the data collected by the e-senses showed a clear evolution according to the cooking method and time. The results helped to determine the cooking method that best preserves the nutritional properties of the vegetables, highlighting the applicability of rapid instrumental methods to interpret the evolution of sensory characteristics. [ABSTRACT FROM AUTHOR]

The present work aimed at evaluating if heavy pig low-protein diets balanced for amino acid (AA) profile affect the quality characteristics of dry cured hams. To the aim, 40 hams obtained by Italian Duroc × Italian Large White pigs fed three different dietary crude protein and indispensable AA levels were compared with those obtained by a conventional Parma ham Protected Designation of Origin diet (C). No physico-chemical (aw, pH), chemical (gross composition, NaCl, lipid peroxidation, non-protein nitrogen, total volatile bases) or sensory characteristics of hams were systematically affected by the administered diet, animal sex or their interaction with the exception of total and subcutaneous fat (the latter measured by an image analysis procedure). Considering gilts, low-protein diets resulted in samples with higher fat content and subcutaneous fat thickness with respect to hams obtained with C diet. In conclusion, low protein diets in the finishing phase of pig breeding could reduce the environmental impact due to nitrogen excretion without significantly affecting ham quality. [ABSTRACT FROM AUTHOR]

Abstract: A combined acoustic–mechanical technique was employed to simultaneously characterise in uniaxial compression mode the texture properties of commercial toasted sliced breads and laboratory-made ones that were made by modifying the amount of sucrose in the recipe. Also an Image Analysis technique was used to describe the morphology of the gas cells. The analysis of the flavour release was performed by means of a commercial electronic nose system. Advanced techniques of multivariate statistical analysis were employed to get the maximum information from the proposed instrumental techniques. Some selected mechanical parameters and flavour release responses are dominant in discriminating sliced bread samples and both express similar information. The Regularised Discriminant Analysis output for the acoustic, mechanical and flavour release data was: Non Error Rate Cross Validated equal to 80.1% in the cross-validation mode. The NERCV % index is an estimation of the predictive potential of the model that was validated according to the leave one out (LOO) method. The LOO procedure removes each sample from the data set, one at a time. The classification model is rebuilt and the class of the removed sample is predicted by using the obtained model. By combining these instrumental characterisation methods, the result of the texture/aroma description of these cellular solids was improved. [Copyright &y& Elsevier]

Snacks were produced by extruding blends of partially-defatted soybean flour with flours from milled or parboiled African-grown rice. The interplay between composition and processing in producing snacks with a satisfactory sensory profile was addressed by e-sensing, and by molecular and rheological approaches. Soybean proteins play a main role in defining the properties of the protein network in the products. At the same content in soybean flour, use of parboiled rice flour increases the snack's hardness. Electronic nose and electronic tongue discriminated samples containing a higher amount of soybean flour from those with a lower soybean flour content.

Polyamidic nanofibrous membranes containing gated silica mesoporous particles, acting as carriers, are described as novel hybrid composite materials for encapsulation and on-command delivery of garlic extracts. The carrier system consists of MCM-41 solids functionalized in the outer surface, with linear polyamines (solid P1) and with hydrolyzed starch (solid P2), both acting as molecular gates. Those particles were adsorbed on electospun nylon-6 nanofibrous membranes yielding to composite materials M1 and M2. FE-SEM analysis confirmed the presence of particles incorporated on the nylon nanofibers. The release of the entrapped molecules (garlic extract) from the P1, P2, M1, and M2 materials was evaluated using cyclic voltammetry measurements. Electrochemical studies showed that at acidic pH P1 and M1 were unable to release their entrapped cargo (closed gate), whereas at neutral pH both materials release their loading (open gate). Dealing with P2 and M2 materials, in the absence of pancreatin a negligible release is observed (closed gate), whereas in the presence of enzyme the load is freely to diffuse to the solution. These newly developed composite nanomaterials, provide a homogeneous easy-to-handle system with controlled delivery and bioactive-protective features, having potential applications on pharmacology, medical and engineering fields.