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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 sativa(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. glaberrimawere characterized by lower expansion rates with respect to those obtained from O. sativa, 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 sativarice. 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.

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 M1and 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 M2materials was evaluated using cyclic voltammetry measurements. Electrochemical studies showed that at acidic pH P1and M1were unable to release their entrapped cargo (closed gate), whereas at neutral pH both materials release their loading (open gate). Dealing with P2and M2materials, 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

This review will focus on the recent advances on nanofibrous membranes (NFM) prepared by electrospinning (ES) applied to modify electrochemical sensors and biosensors. Most relevant applications of NFM include their used as selective barrier toward diffusion, protective coatings against fouling, conductive substrates for sensing applications, catalytic and biocatalytic membranes. The main advantages and drawbacks of these applications are critically assessed.

A new multi‐flow‐through amperometric detectors design was employed as a sensors array system for the detection of flavor related phenols. Relevant parameters of the amperometric detection were examined and optimized. The multivariate analytical signal was processed with chemometric analysis for exploring and classifying the tea beverages. Multivariate regression was used to correlate the astringency value of several tea beverages, obtained by the UNI (Italian Organization for Standardization) sensory profile test, with the signals collected by this amperometric electronic tongue.

In this paper a novel approach for performing discriminative test in food quality control is reported. The method is based on the use of an electronic nose equipped with 10 Metal Oxide Semiconductor Field Effect Transistor (MOSFET) sensors, 12 Metal Oxide Semiconductor (MOS) sensors and one humidity sensor. The pattern of the sensor responses generated by the electronic nose has been used for performing “objective” triangle tests in several food products. The results were compared with the data obtained by using standard methodology (triangle test) of sensory analysis (UNI ISO 4120 Norm). The e‐nose is able to classify correctly all the samples under study, while the sensory panel is able to correctly perform the test only in 50% of the cases. As compared with the sensory test, the electronic nose methodology is simple, rapid and results suggest that it can be useful tool for performing discriminative testing.

Seventy samples of honey of different geographical and botanical origin were analysed with an electronic nose. The instrument, equipped with 10 Metal Oxide Semiconductor Field Effect Transistors (MOSFET) and 12 Metal Oxide Semiconductor (MOS) sensors, was used to generate a pattern of the volatile compounds present in the honey samples. The sensor responses were evaluated by Principal Component Analysis (PCA) and Artificial Neural Network (ANN). Good results were obtained in the classification of honey samples by using a neural network model based on a multilayer perceptron that learned using a backpropagation algorithm. The methodology is simple, rapid and results suggest that the electronic nose could be a useful tool for the characterisation and control of honey.

In this paper a rapid method based on a FIA (flow injection analysis) system with amperometric detection for the evaluation of ascorbyl 6-palmitate in foods is described. The selectivity of the proposed method is related to the low anodic potential applied to the working glassy carbon electrode (+0.1 V vs. Ag/AgCl) that leaves out interferences from ascorbic acid and phenolic compounds. By flow injection analysis, under optimised conditions, the calibration curve was linear in the range 0–20 mg l⁻¹ and the detection limit was 0.2 mg l⁻¹.