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A novel approach based on a molten multicomponent precursor source has been applied for the MOCVD fabrication of high-quality CaCu3Ti4O12 (CCTO) thin films on various substrates. The adopted in situ strategy involves a molten mixture consisting of Ca(hfa)(2)center dot tetraglyme, Ti(tmhd)(2)(O-iPr)(2), and Cu(tmhd)(2)[Hhfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione; tetraglyme) 2,5,8,11,14-pentaoxapentadecane; Htmhd = 2,2,6,6-tetramethyl- 3,5-heptandione; O-iPr) isopropoxide] precursors. Film structural and morphological characterizations have been carried out by several techniques [X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM)], and in particular the energy filtered TEM mapping and X-ray energy dispersive (EDX) analysis in TEM mode provided a suitable correlation between nanostructural properties of CCTO films and deposition conditions and/or the substrate nature. Correlation between the nanostructure and optical/dielectric properties has been investigated exploiting spectroscopic ellipsometry.

Recently, vegetable oils have been widely used in several industrial fields as food additives, biofuels, cosmetic ingredients, packaging materials, or pharmaceutical compounds. In this study, we investigated the extraction of lipids from spent coffee grounds using an innovative system and the hydrofluorocarbon Norflurane, as solvent. Extraction experiments were performed on matrices at different levels of moisture under a recirculating solvent flow in the pressure range 5−11 bar. The results confirmed the effectiveness of the novel extraction process on wet, dried and partially dried matrices, and the oil yields and the extraction times (approximately 92% in 75, 90 and 285 min respectively) were comparable with those obtained using the more expensive supercritical CO2 process. A kinetic approach was used to model the extraction rates of wet, dry and partially dried samples. It showed that a partial drying of the SCG promoted the solubilization of oil in Norflurane during the first extraction stage and improved the contact between Norflurane and the oily solute. The fatty acid profiles of the extracts were determined and the results revealed the presence of palmitic (C 16:0) and linoleic (C 18:2) acids, as major components, and stearic (C 18:0) and oleic (C 18:1) acids, as minor components.

Coeliac disease is an increasingly recognised pathology, induced by the ingestion of gluten in genetically predisposed patients. Undigested gliadin peptide can induce adaptive and innate immune response that unleash the typical intestinal mucosal alterations. A growing attention is paid to alternative therapeutic approaches to the gluten-free diet: one of these approaches is the use of probiotics and/or postbiotics. We performed lactic fermentation of rice flour with and without pH control, using Lactobacillus paracasei CBA L74 as fermenting strain. We evaluated bacterial growth, lactic acid production during fermentation and gliadin peptide P31-43 entrance in CaCo-2 cells with and without pH control. When pH control was applied no differences were observed in terms of bacterial growth; on the contrary, lactic acid production was greater, as expected. Both samples could inhibit the P31-43 entrance in CaCo-2 cells but the effect was significantly greater for samples obtained when the pH control was applied.

The mathematical modeling of fermentation processes allows for the formulation of predictions about the kinetics of biomass growth and metabolite production as well as setting or verifying the best operative conditions in view of the economical convenience of the process. For this purpose, we performed a kinetic study of a rice flour fermentation process using Lactobacillus paracasei CBA L74 with and without pH control, the pH value was set to 5.8 under pH control. Monod, Logistic, and Contois models were proposed to describe the bacterial growth rate in both conditions. The best mathematical model, which was able to describe the experimental data obtained without pH control, was the Contois model, as the specific growth rate was influenced by both the glucose reduction (from 14.31 g/L to 10.22 g/L) and the biomass production (2 log growth) that occurred during fermentation. Conversely, when pH control was implemented, both Monod and Contois models satisfactorily described the specific growth rate trend. The estimated kinetic parameters confirmed that biomass production (2 log growth) and glucose consumption (from 14.31 g/L to 6.06 g/L) did not affect the microorganism’s growth capacity when the fermenting medium was maintained at an optimal pH. The lactic acid production rate described by the Luedeking–Piret model did not appear to be linked to growth in the absence of pH control while, on the other hand, this model was unsuitable for describing the experimental lactic acid concentration when pH control was applied. The kinetic modeling of lactic acid production and the percentage of added glucose in the protocol with controlled pH will be optimized in the future.

Cereals are becoming interesting substrates to be fermented to obtain new functional foods. For this reason, an enzymatic pretreatment of a wheat flour suspension using amylase was investigated in order to guarantee the feasibility to ferment a cereal-based substrate at a solid content higher than that used in past experimentations. Trials with and without amylase pretreatment, using a 52% w/v wheat flour water suspension, were carried out to evaluate the fermentation feasibility; mixing tests with a food dye were performed to verify the suspension homogeneity. The pretreated suspension, whose starch was hydrolyzed for about 80% by α-amylase, was then fermented (37°C, 24h) by Lactobacillus paracasei CBA-L74. Starting from pH value 5.75, microbial concentration 1.89 × 106 CFU/ml and lactic acid 0 mg/L, final values of 3.93, 3 × 108 CFU/ml and 6,251 mg/L were found after 24 hr of fermentation. The untreated suspension went to gelation and was impossible to ferment because its consistency was like a dough and the mixing system was not suitable to ensure mixing. Practical applications: The aim of the present study was the handling and the fermentation of cereal-based substrate at high solid content (52% w/v), through a preliminary amylase pretreatment. The fermentation of such a solid content could guarantee the production of a greater quantity of solid fermented matrix and this could considerably reduce drying times with greater productivity at a low cost.

Studies of the ability of probiotics to ferment cereal flours are necessary to obtain products with enhanced nutritional value. In this study, Lactobacillus paracasei CBA-L74 was used to ferment cereal aqueous mixtures containing both oat (7.5% w/v) and rice flours (7.5% w/v), with and without glucose, to understand whether glucose addition could have any effect on growth and metabolism. Viability, pH, metabolites production during fermentation (24 h, 37 °C) and substrates reduction were analysed. The strain showed good growth in the cereal aqueous mixture both with and without glucose addition, but suspensions prepared with glucose showed the best results. A bacterial concentration of 7 log CFU mL−1, a pH value of 4.70 and lactic acid production of 1250 mg L−1 were achieved when fermentation was performed without glucose addition, while in the presence of glucose, a t24 bacterial growth of 8 log CFU mL−1 was reached, with a pH value of 3.11 and lactic acid production of 6050 mg L−1., Food science, Food technology, Nutrition, Lactobacillus paracasei CBA L74, Fermented food, Rice flour, Oat flour, Glucose, Probiotics

The consumption of vegetable oils has increased in recent years due to their nutraceutical properties. There is growing scientific research interest in the development of innovative, efficient and sustainable extraction techniques capable of separating lipid fractions from vegetal matrices. In this study, we introduce an innovative technique for extracting lipids from bilberry seeds that uses Norflurane, a hydrofluorocarbon, as the solvent under subcritical conditions. Preliminary extraction experiments were carried out using bilberry seeds in the waste material from the bilberry drupe valorization process. Different granulometric bilberry fractions were selected, suitably crushed, and sized prior to extraction. An extraction efficiency of 91% of the total lipid content was obtained for the ground fraction with grains 450−710 μm in size. The main fatty acids present in the lipid extracts were oleic, linoleic and α-linolenic acids. The ratio of unsaturated-to-saturated fatty acids was determined to be 11.63, with a ω6/ω3 ratio of 1.06.

The feasibility of developing a dry legume-based functional product using a fermentation process carried out on a 10% w/v navy bean suspension, in a lab-scale stirred batch reactor was studied. After soaking and cooking dried navy beans, the fermentation tests performed on the resulting medium using Lactobacillus paracasei CBA L74 showed a maximum bacterial count of 109 CFU/mL after 20 hr and a maximum lactic acid concentration of 1.9 g/L after 16 hr of process time. A freeze-drying process was conducted on the fermented bean suspension, showing a two-log microbial reduction and a bacterial viability in the resulting probiotic powder of 3.7 × 108 CFU/g.

Banana puree, due to its nutritional composition, is a good substrate for fermentation in the development of probiotic products. The production of banana puree mainly consists of three phases, i.e., raw material pretreatment, heat treatment, and the addition of anti-browning agents. In this study, we conducted three experimental protocols to evaluate the effect of ripeness grade, heat treatment, and ascorbic acid addition on fermentation performance. At the end of each protocol, the substrate was subjected to the fermentation process (37 °C, 48 h), and then measurements of pH reduction, microbial growth, and lactic acid production were used as markers in the analysis of fermentation performance. Ripe bananas produced better results than unripe bananas whose fermentation appeared to be inhibited. Therefore, ripe bananas were used to test the effect of two different heat treatments (sterilization (121 °C, 20 min) versus tyndallization (70 °C, 30 min, 37 °C, 30 min, 70 °C, 30 min)) on banana puree fermentation, and no significant differences were observed. Finally, 500 or 1000 ppm of ascorbic acid, normally used as an anti-browning agent, was added to ripe tyndallized bananas. No differences in fermentation results were observed between the two tested conditions, though values obtained for growth and lactic acid production were significantly lower than those from fermentation of banana puree without ascorbic acid.

The structural and the electronic properties of monolayer graphene made by chemical vapor deposition and transferred on various oxide substrates ( SiO 2 , Al 2 O 3 , and HfO 2 ) are investigated by Raman Spectroscopy and Atomic Force Microscopy in order to highlight the influence of the substrate on the features of p-doping obtained by O 2 thermal treatments. By varing the treatment temperature up to 400 °C, the distribution of the reaction sites of the substrates is evaluated. Their total concentration and the consequent highest doping available is determined and it is shown that this latter is linked to the water affinity of the substrate. Finally, by varing the exposure time to the gas up to 2 h, the kinetics of doping is investigated. The doping process is found to be better described by a diffusion limited kinetic model, ascribable to the diffusion of O 2 in the interstitial space between graphene and the substrate. After this step, the doping process is completed by a faster redox reaction between O 2 adsorbed to graphene and interstitial H 2 O .

A cold plasma prototype electrode discharge apparatus to perform polymer surface treatment is described. The plasma generator, operating with oxygen and/or nitrogen, works in glow regime at low pressure (10 mbar) and at relatively high gas flow rate, in the 110–340 1/h range. The effects of treatments on PET monopolyester and glass fibre reinforced plastics (GFRP) surfaces are analysed. The treatment points out, in all operating conditions, an increase of both wettability (PET) and adhesivity (GFRP). The treatment times obtained are one order of magnitude lower than those of the traditional treatment apparatus.