Effect of high pressure homogenization (HPH) on the rheological properties of a fruit juice serum model

High pressure homogenization (HPH) is a non-thermal technology that has been widely studied as a partial or total substitute for thermal food processing. The present work evaluated the effect of HPH on the rheological properties of a fruit juice serum model, designed to be similar to tomato juice serum. Product viscosity decreased due to the increase in homogenization pressure, and could be modelled well using two functions (power-sigmoidal and exponential; R² > 0.98). The serum model processed at 200 MPa showed a viscosity decrease of 20% when compared to the original. Since fruit juice rheology is defined by the interactions occurring between the dispersed phase (suspended particles) and the solution (serum), the expected fruit juice behaviour was then discussed.     

Evolution of grape seed flavan‐3‐ols during ripening of different grape cultivars

Evolution of both catechin and epicatechin grape seed content was established for ten white and six red grape varieties during the ripening period. Chemometric techniques (cluster analysis and partial least squares analysis) were used for data analysis. An initial increasing stage and a final stabilisation step for both compounds have been observed for most varieties during ripening, including both red and white grape varieties. On the other hand, three red varieties (Tintilla de Rota, Tempranillo and Graciano) and two white varieties (Vijiriega and Muscat á Petit Grain) kept away from the rest showed particular trends. Graciano was the only cultivar that presented differences in catechin and epicatechin behaviour during its ripening period.     

Influence of dietary fat on pork eating quality

This study compared the influence of dietary fat sources on meat quality, fatty acid composition and sensory attributes in pork. The experiment was conducted with 43 entire male pigs (Pietrain×(Landrace×Large White)) which were fed a basal diet without added fat (control diet) or supplemented with different sources of fat: animal fat (1%, AF1; 3%, AF3), soyabean oil (1%, SBO1) and calcium soaps of palm oil (1%, CaSPO1). Dietary fat supplementation did not significantly affect ultimate pH, colour, Warner-Bratzler shear force values, sensory attributes or SFA. Pigs fed SBO1 had the lowest proportion of MUFA and the highest of PUFA. In conclusion, these dietary fat sources could be recommended for inclusion in diets, at these levels, with no detrimental effect on eating quality. Despite finding no significant differences, the PCA afforded a comprehensive view of the predominating attributes of pork from animals fed the different fats.     

Selective Oxidative Degradation of Organic Pollutants by Singlet Oxygen-Mediated Photosensitization: Tin Porphyrin versus C(60) Aminofullerene Systems

This study evaluates the potential application of tin porphyrin- and C(60) aminofullerene-derivatized silica (SnP/silica and aminoC(60)/silica) as (1)O(2) generating systems for photochemical degradation of organic pollutants. Photosensitized (1)O(2) production with SnP/silica, which was faster than with aminoC(60)/silica, effectively oxidized a variety of pharmaceuticals. Significant degradation of pharmaceuticals in the presence of the 400-nm UV cutoff filter corroborated visible light activation of both photosensitizers. Whereas the efficacy of aminoC(60)/silica for (1)O(2) production drastically decreased under irradiation with λ > 550 nm, Q-band absorption caused negligible loss of the photosensitizing activity of SnP/silica in the long wavelength region. Faster destruction of phenolates by SnP/silica and aminoC(60)/silica under alkaline pH conditions further implicated (1)O(2) involvement in the oxidative degradation. Direct charge transfer mediated by SnP, which was inferred from nanosecond laser flash photolysis, induced significant degradation of neutral phenols under high power light irradiation. Self-sensitized destruction caused gradual activity loss of SnP/silica in reuse tests unlike aminoC(60)/silica. The kinetic comparison of SnP/silica and TiO(2) photocatalyst in real wastewater effluents showed that photosensitized singlet oxygenation of pharmaceuticals was still efficiently achieved in the presence of background organic matters, while significant interference was observed for photocatalyzed oxidation involving non-selective OH radical.     

Integration of a light mobility urban scale hydrogen refuelling station for cycling purposes in the transportation market

Road transportation consists of a significant contributor to total greenhouse gas emissions in developed countries. New alternative technologies in transportation such as electric vehicles aim to reduce substantially vehicle emissions, particularly in urban areas. Incentives of using two-wheel electric vehicles such as bicycles in big cities centres are promoted by local governments, and in fact, some countries are already trying to adopt this transition. An interesting case consists of the use of hydrogen fuel cells in such vehicles to increase their driving range under short refuelling times. To this end, this paper investigated the social and financial prospects of hydrogen infrastructure for city-oriented fuel cell electric vehicles such as bicycles. The results of the research indicated that a light mobility urban hydrogen refuelling station able to provide refuelling processes at pressures of 30 bar with a hydrogen fuel cost of 34.7 €/kgH₂ is more favourable compared to larger stations.     

Finite line-source model for borehole heat exchangers: effect of vertical temperature variations

A solution to the three-dimensional finite line-source (FLS) model for borehole heat exchangers (BHEs) that takes into account the prevailing geothermal gradient and allows arbitrary ground surface temperature changes is presented. Analytical expressions for the average ground temperature are derived by integrating the exact solution over the line-source depth. A self-consistent procedure to evaluate the in situ thermal response test (TRT) data is outlined. The effective thermal conductivity and the effective borehole thermal resistance can be determined by fitting the TRT data to the time-series expansion obtained for the average temperature.     

Phytochemical characterisation for industrial use of pomegranate (Punica granatum L.) cultivars grown in Spain

BACKGROUND: The study of 15 pomegranate cultivars was carried out in order to demonstrate the wide diversity among the quality of Spanish pomegranates, and compared to ‘Wonderful’ cultivars, which are used worldwide for industrial purposes. Juice yield, quality parameters, organic acids and sugars, colour, vitamin C, ellagic acid, punicalagins, anthocyanins, total phenolic content, antioxidant capacity, and sensory properties were measured. RESULTS: A considerable variation was found between ‘Wonderful’ and pomegranates of Spanish origin, according to both cluster analysis and principal component analysis. ‘Wonderful’ juices displayed large antioxidant activity and a polyphenol content with very high acidity. In contrast, ‘Mollar de Elche’ showed fewer anthocyanins although it had very superior organoleptical properties. In addition to a high content in ellagitannins, ‘Valenciana’ juices had exclusive colour parameters. CONCLUSION: These useful results can be employed by the juice processing industry to select those properties more interesting for the development of pomegranate juices that are organoleptically attractive and rich in bioactive compounds. Copyright © 2011 Society of Chemical Industry     

Effect of additives on the stoichiometry of iron sulphides formed during liquefaction of a Powhatan No. 5 coal

Transformations of pyrite in a Powhatan No. 5 is studied using Mössbauer spectroscopy. Stoichiometry of the resultant pyrrhotites is shown to be influenced by the H₂S partial pressure in the reactor. Higher H₂S partial pressure yields pyrrhotites with more iron deficiency. Variation in the H₂S partial pressure is achieved through the addition of either pyrite, troilite or pyrrhotite. It is also shown that pyrrhotites having the same average at% Fe may have widely differing vacancy distribution on the Fe sites.     

Physicochemical and antioxidant properties of non‐refined sugarcane alternatives to white sugar

Antioxidant properties of commercial sugarcane‐derived products were analysed to study their suitability for being used as functional ingredients. Cane honey, several jaggeries and several brown sugars were selected from the market and analysed in terms of physicochemical characteristics and antioxidant properties, and compared with white refined sugar (twelve products in total). Moisture, water activity, total soluble solids, pH, colour and sugar profile are reported. As for antioxidant properties, total phenols and flavonoid content, as well as antiradical ability (DPPH˙ and the TEAC‐ABTS methods), are given. All sugarcane products contained phenols and flavonoids and exhibited in vitro antioxidant activity, determined by degree of refining. Among the alternatives analysed, jaggeries and cane honey showed the best antioxidant properties. Thermal treatment did not significantly affect the antioxidant capacity of sugarcane products, especially jaggeries. As sugar‐rich products are widely consumed worldwide, the use of non‐refined sugarcane derivatives in food formulation is encouraged.