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It is generally held that the content of several free amino acids and dipeptides is closely related to the energy-supplying metabolism of skeletal muscles. Metabolic characteristics of muscles are involved in the variability of meat quality due to their ability to influence the patterns of energy metabolism not only in living animal but also during post-mortem time. Within this context, this study aimed at establishing whether the concentration of histidine dipeptides can affect muscle post-mortem metabolism, examining the glycolytic pathway of three chicken muscles (Pectoralis major, extensor iliotibialis lateralis and gastrocnemius internus as glycolytic, intermediate and oxidative-type, respectively) selected based on their histidine dipeptides content and ultimate pH. Thus, a total of 8 carcasses were obtained from the same flock of broiler chickens (Ross 308 strain, females, 49 days of age, 2.8 kg body weight at slaughter) and selected immediately after evisceration from the line of a commercial processing plant. Meat samples of about 1 cm3 were excised from bone-in muscles at 15, 60, 120 and 1,440 min post-mortem, instantly frozen in liquid nitrogen and used for the determination of pH, glycolytic metabolites, buffering capacity as well as histidine dipeptides content through 1H-NMR. Overall results suggest that glycolysis in leg muscles ceased already after 2 h post-mortem, while in breast muscle continued until 24 h, when it exhibited significantly lower pH values (P

This work studied water state of honey during crystallization, obtained statically and dynamically, by differential scanning calorimetry (DSC), water activity (aw) assessment and time domain nuclear magnetic resonance (TD-NMR). Crystallization was induced by adding 5% of crystallized honey to three honey samples with different fructose/glucose ratio, the key characteristic for honey crystallization. Samples were stored at 14 °C. Dynamic crystallization was obtained by using an impeller. DSC showed that the dynamic crystallization was faster than the static one, the latter characterized by two phases, showing different rates. The crystallization rate did not affect aw, that remained below 0.600. TD-NMR allowed to separately observe two kinds of protons, both pertaining to liquid sugars, one chemically exchanging with water and one not exchanging with it. The combination of techniques allowed speculating that the two crystallization methods led to crystals of different size and shape.

The thermal and mechanical properties of a lightweight alkali bonded material were investigated in correlation with the microstructure and porosity. The material was produced using fine granules of expanded perlite as raw powder and potassium di-silicate aqueous solution as alkaline activator, instead of the commonly used sodium silicate, to improve thermal performances. After consolidation, the material was subjected to microstructural analyses, as well as to thermo-physical and mechanical tests. Density was 467 ± 40 kg·m−3, the total porosity 80 vol%, the average pore size 0.2 µm and compressive strength was 1.5 ± 0.5 MPa. It was observed that, besides the action of potassium di-silicate as an alkali binder, expanded perlite granules reacted on the surface forming geopolymer nano-precipitates. Laser Flash Method was employed to evaluate the whole thermal behavior within the temperature range 25–550 °C: thermal conductivity was 0.084 m−1K−1 at 25 °C and 0.121 W·m−1K−1 at 550 °C. At high temperature, the thermal conductivity resulted similar or even lower when compared with commercial perlite – sodium silicate materials with lower densities in the range 180–260 kg/m3. Results show that lightweight alkali bonded expanded perlite materials can be produced with improved thermal properties by exploiting potassium silicate and overcoming the poor temperature resistance of organic binders.

In the latest years, the interest about Phase Change Materials (PCM) in building applications grew in force of their capability to adsorb heat and limit in-out building heat exchanges. The main problem is how to introduce PCM into the building envelope, also in case of ventilated facades. For this purpose, a ceramic foam was studied. Two different batches based on porcelain stoneware and soda-lime glass scraps were prepared to understand the involved bloating phenomena. Suitable bulk density and porous microstructure were achieved by adding a foaming agent and batch optimization. Specimen size was scaled up (from ∅ 3 cm to 15 × 15 cm) and its effect on bloating, PCM incorporation, and thermal properties was studied. Furthermore, different firing temperatures and heating rates were evaluated. The whole study was focused to disclose possible drawbacks in the industrial transfer of the PCM-bearing composite production.

Fabric Reinforced Cementitious Matrix (FRCM) materials are composed of a dry fiber grid embedded in an inorganic matrix, which may contain short fibers. These materials are particularly well-suited for the reinforcement of masonry structures due to their high compatibility with the substrate, vapor permeability and durability against environmental agents. The most important information needed for the characterization of these composite systems, for use as strengthening materials of masonry structures, are the tensile behaviour and the shear bond properties. A Round-Robin Test was organized by the RILEM Technical Committee 250-CSM and the Italian association Assocompositi in order to experimentally characterize different FRCM systems composed of PBO, carbon, glass, basalt, aramid and steel textiles embedded in cementitious or lime-based mortars. The systems were tested at different universities and research centers in Europe in order to investigate the influence of samples preparation, test set-up and instrumentation. In this paper, the experimental tests performed on Carbon-FRCM systems are described and discussed. Important aspects are analyzed herein: differences in the testing procedure and instrumentation, influence of textile geometry and mechanical properties of the constituent materials, importance of specimen preparation and curing conditions. Moreover, a comparison between tensile and shear tests is reported in order to determine a reliable procedure towards the complete characterization of an FRCM material.

The aim of this work was to evaluate the effect of pulsed electric field (PEF) pre-treatment on mass transfer phenomena, water distribution and some physico-chemical parameters of osmo-dehydrated organic strawberries. For PEF treatments 100 near-rectangular shaped pulses, with fixed pulse width of 100 μs and repetition time of 10 ms were used. Electric fields strength applied were 100, 200 and 400 V cm−1. Afterwards, samples were subjected to OD treatments carried out in two different hypertonic solutions (40% w/w), one with sucrose and the other one with trehalose. The results shown that PEF treatment positively affected the mass transfer during OD even at the lowest electric field strength applied (100 V/cm), partially preserving the cell viability and maintaining at the same time the fresh-like characteristics of strawberries.

This work aimed to determine the effect of homogenization pressures (HPH) and addition of trehalose on the functional and technological properties of low pulp mandarin juice (LPJ). A set of experiments was designed, combining a non-targeted metabolomic 1 H NMR based approach together with suspended pulp and transmittance, hesperidin, vitamin C and antioxidant activity analysis. Suspended pulp increased with HPH and trehalose addition. Flavonoid hesperidin initially decreased with HPH but trehalose addition resulted in less flavonoid degradation during storage, increasing the effect with the HPH. Vitamin C was not affected by trehalose and pressure treatment but more Vitamin C degradation was observed in trehalose samples during storage. Antiradical activity improvement by trehalose was conditioned by homogenization pressures and specific bioactive compounds. 1 H NMR based approach highlighted the HPH effect on the microbiological aspects of low pulp mandarin juice by the identification of key molecules responsible of the microorganism profile evolution during storage.

Nuclear magnetic resonance (NMR) spectroscopy has a long tradition as a powerful platform in the hands of modern food scientists, with several applications related to food safety, traceability and authenticity. The continual advances in instrumental sensitivity and electronic stability, together with rapid growth in new, potent algorithms for multivariate data analysis, facilitate the use of NMR spectroscopy as a competitive, complementary analytical platform for observing the food metabolome. By adapting the holistic views of metabolomics research, foodomics emerges as a new discipline bringing food science and nutritional research closer together. This review mostly focuses on recent efforts dedicated to extraction and interpretation of NMR data, rather than providing technical details about their acquisition. With this aim, we present new trends in the exploitation of the information gained by NMR of food matter. We critically describe and illustrate, via representative examples, the limitations and the counterbalancing advantages of the technique.

Pulsed electric field (PEF) technology is gaining momentum as a pre-treatment to enhance mass transfer of vegetable tissues obtained by further processing. In this study PEF pre-treatment increased osmotic dehydration (OD) effectiveness, in terms of water loss and solid gain in apples, as a function of electric field strength and number of pulses. Mass transfer was particularly high when average electric fields of 250 and 400 V cm -1 were applied. Time domain nuclear magnetic resonance (TD-NMR), with the use of a contrast agent, clarified structural changes that drive mass transfer. Treatments at 100 V cm -1 redistributed water between vacuole, cytoplasm and extracellular space, while at 250 and 400 V cm -1 the membrane breakages caused the loss of cellular compartmentalization. Two non-destructive and fast acquirable parameters, the longest measured relaxation time (T 2 ) and water self diffusion coefficient (D w ), allowed the separate and accurate observation of PEF treatment and osmotic dehydration effects. Industrial relevance The developed non-destructive method, here described, allows the measure of the effects of PEF treatment on apple tissue which can be exploited to have reliable control of the process within minutes. Since mass transfer parameters depend on subcellular water redistribution, the present work provides a tool to boost the development and optimization of agri-food processes on fresh vegetable tissues.

This research compared the distribution and mobility of water in the longissimus thoracis muscle of 51 Apulo-Calabrese and 52 crossbred pigs differing in growth performances. The Apulo-Calabrese and crossbreed pigs were fed the same diet and slaughtered at 135 and 155 kg live weight, respectively. Besides meat quality measurement, water status was assessed from transverse relaxation time (T2) weighted signals registered by Time Domain Nuclear Magnetic Resonance (TD-NMR). A mixed model indicated that Apulo-Calabrese pigs had higher a* (P-value

Investigations were made in order to evaluate the influence of the flour type, chemical acidification and fermentation on characteristics of doughs obtained with durum wheat and KAMUT® Khorasan flour. Doughs were observed immediately after mixing, 90 and 360 min of leavening at 30 °C. Fundamental rheology, yeasts heat production by isothermal microcalorimetry and the interaction between water and biopolymers by means of time domain nuclear magnetic resonance were evaluated. In addition aromatic metabolite development was followed by means of the combined application of gas-chromatography and electronic nose. KAMUT® Khorasan flour was found to be more suitable than durum wheat for the fermentation processes tested, especially at acidic conditions, as shown by the increase of the volume and the metabolic heat production by yeast. In acidified dough the pattern of volatile metabolites allowed a clear distinction between the types of dough. Moreover the water/starch proton pool was characterized by higher T2 values in the KAMUT® Khorasan samples.

Quality definition of food includes several complex factors like physical, compositional and microbial features, modifications induced by technological processes or storage, nutritional value and safety. Foodomics is a holistic approach applying omics technologies to observe food along the entire production/consumption chain. In the present review, we present key applications of nuclear magnetic resonance in foodomics described in the 2012–2015 period, in the quest for robust and thorough information required by the scientific community. In doing so, we summarize the issues connected to food traceability and authenticity, composition and physical characteristics, processing and storage and health, that mostly impact food quality.

To ease the mass exchange in fruit tissues, cutting and blanching are traditionally performed. However, recently, unconventional methods such as sonication are becoming more popular, which cause several alterations of physical and chemical properties as well as microstructure changes. The aim of this work was to evaluate the distribution of water inside the cranberry fruits, microstructural changes and sugars content, following traditional and sonication pre-treatments in osmotic solutions. TD-NMR spectroscopy was used to measure the transverse relaxation time (T2) and intensity of proton pools in different cellular compartments. The microstructure of the samples was evaluated by SEM microscopy, sugars content by HPLC and sucrose melting temperature and enthalpy by DSC. Different pre-treatments appeared to promote microstructure alterations and loss of water from vacuole and cytoplasm/extracellular space, more pronounced in cut and blanched samples. Cutting and blanching followed by osmotic dehydration with assisted sonication eased sucrose penetration into the tissue.

In this study, six enological tannins (T1–T6) from different source were analysed by selected analytical techniques, including UV–Vis, FTIR, NMR, SEC, LC-MS/MS and electronic nose. Moreover, the samples were tested for their antioxidant activity. Spectra and chromatograms are considered as a fingerprint with a pattern that is distinctive for a given type of sample. In particular, tannins showed the maximum UV–Vis absorbance (λmax) at 273–280 nm, the inflection point (λmin) at 247–264 nm, and the ratio λmax/λmin was 1.03, 1.35, 1.67, 1.36, 2.15, 2.02 for tannin T1–T6, respectively. The FTIR analysis of tannins showed the presence of most important absorption bands at 1522, 1453, 1380, 1350, 1328, 1286, 1210, 1148 and 1044 cm−1. Besides, SEC and NMR analysis allowed to sort the tannins according to their average DP as follows: T1 > T2 = T4 > T3 > T6 = T5. Based on this multiple techniques approach three condensed tannins (sample T3, T5 and T6) were clearly identified, together with two mixtures of hydrolysable tannins (sample T1 and T2), whereas one sample (T4) showed a peculiar pattern different from the commercial tannin commonly used in enology.

The capacity of human lactobacilli and bifidobacteria to produce metabolites under conditions that may prevail in the human intestine has been studied "in vitro". However, the effect of systematic probiotic consumption on human metabolic phenotype has not been investigated in faeces. This paper shows the potential for the use of (1)H Nuclear Magnetic Resonance ((1)H NMR) spectroscopy for studying the changes of the metabolic profiles of human faecal slurries. Faeces of 16 subjects, characterized by different natural levels of lactobacilli and bifidobacteria were recovered before and after 1 month of supplementation with a synbiotic food based on Lactobacillus acidophilus, Bifidobacterium longum and fructooligosaccharides, and analyzed by (1)H NMR. Multivariate statistical approach has been applied to the data obtained and particularly Canonical Discriminant Analysis of Principal Coordinates (CAP). More than 150 molecules belonging to short chain fatty acids, organic acids, esters, alcohols and amino acids were detected and quantified in the samples considered. The number and the extent of these molecules in faecal slurries were strongly affected by the synbiotic food consumption and gave rise to characteristic metabolic signature. In particular, the short chain fatty acid concentrations significantly increased while the amino acids contents decreased. The comparison of the data indicated that the intake of the synbiotic food alters the host metabolism in a measure dependent on the initial level of lactobacilli and bifidobacteria detected in the faecal specimens. The analysis of (1)H NMR profiles with CAP allowed a separation of faecal samples of the subjects on the basis of the synbiotic food intake. The multivariate statistical approach used demonstrated the potential of NMR metabolic profiles to provide biomarkers of the gut-microbial activity related to dietary supplementation of probiotics.

Objective. – To describe the effect of Coenzyme Q10 (CoQ10) (added to either a fibrate, or polyunsaturated fatty acids (PUFA) or association of both) in patients affected by massive hypertriglyceridemia (MHTG) resistant to fibrates and PUFA. Design. – Open, sequential, comparative intervention study. Setting. – Specialised centres for dyslipidemia management. Subjects. – Fifteen subjects (mean age: 45.1 ± 12.5 years) affected by MHTG and hyporesponsive to either fibrates, or PUFA, or fibrates-PUFA association, and 15 age-matched subjects regularly responders to PUFA and fenofibrate treatment. Interventions – Treatment for periods of 6 weeks each with the following consecutive treatments: CoQ10 150 mg/day, PUFA 3000 mg/day, fenofibrate 200 mg/day, PUFA 3000 mg/day + fenofibrate 200 mg/day, PUFA 3000 mg/day + CoQ10 150 mg/day, fenofibrate 200 mg/day + CoQ10 150 mg/day, and finally, fenofibrate 200 mg/day + PUFA 3000 mg/day + CoQ10 150 mg/day. Results. – CoQ10 supplementation did not improve any monitored parameter in the control group except for systolic and diastolic blood pressure, creatinine and Lp(a) plasma levels, both during fenofibrate and/or PUFA treatment. In MHTG group, CoQ10 supplementation significantly improved TG, TC, Lp(a), uric acid and blood pressure during fenofibrate treatment, but only Lp(a) and blood pressure during PUFA treatment. Fenofibrate appeared to have better effect on hsCRP and γ -GT plasma levels than PUFA. No significant change was observed in any group and under any treatment in regards to homocysteinemia, PAI-1, or t-PA. Conclusion. – Even though the mechanism of action through which the effects were obtained is yet to be elucidated, adding CoQ10 to fenofibrate could improve the drug's efficacy in MHTG patients not responding to fenofibrate alone.