Quinoa, Chenopodium quinoa Willd., is an Amaranthacean, stress-tolerant plant cultivated along the Andes for the last 7000 years, challenging highly different environmental conditions ranging from Bolivia, up to 4.500 m of altitude, to sea level, in Chile. Its grains have higher nutritive value than traditional cereals and it is a promising worldwide cultivar for human consumption and nutrition. The quinoa has been called a pseudo-cereal for botanical reasons but also because of its unusual composition and exceptional balance between oil, protein and fat. The quinoa is an excellent example of 'functional food' that aims at lowering the risk of various diseases. Functional properties are given also by minerals, vitamins, fatty acids and antioxidants that can make a strong contribution to human nutrition, particularly to protect cell membranes, with proven good results in brain neuronal functions. Its minerals work as cofactors in antioxidant enzymes, adding higher value to its rich proteins. Quinoa also contains phytohormones, which offer an advantage over other plant foods for human nutrition.

22The production of condensate compounds from the degradation of benzene by OH radical 23 chemistry was studied. Secondary organic aerosol (SOA) formation was investigated in the 24 EUPHORE (European Photoreactor) simulation chambers. Experiments were performed under 25 different OH-production conditions -addition of H 2 O 2 , NO or HONO -, in a high-volume 26 reactor, with natural light and in the absence of seed aerosols. The consumption of 27 precursor/reagents, the formation of gas-phase and particulate-phase products and the temporal 28 evolution of aerosol were monitored. Several aerosol physical properties -mass concentration, 29 overall aerosol yield, particle size distribution and density -were determined and found to be 30 clearly dependent on OH radical production and NO x concentrations. Furthermore, the use of 31 one and/or two products gas-particle partitioning absorption models allowed us to determine the 32 aerosol yield curves. The SOA yield ranged from 1.6 to 9.7 %, with higher SOA formation 33 under low-NO x conditions. Chemical characterization of the SOA was carried out, determining 34 multi-oxygenated condensed organic compounds by a method based on the gas 35 chromatography-mass spectrometry technique. Several ring-retaining and ring-cleavage 36 products were identified and quantified. The compounds with the highest percentage 37 contribution to the total aerosol mass were 4-nitrobenzene-1,2-diol, butenedioic acid, succinic 38 acid and trans-trans-muconic. In addition, a multigenerational study was performed comparing 39 with the photo-oxidations of phenol and catechol. The results showed that although the mass 40 concentration of SOA produced was different, the physical and chemical properties were quite 41 similar. Finally, we suggest a general mechanism to describe how changes in benzene 42 degradation pathways -rate of OH generation and concentration of NO x -could justify the 43 variation in SOA production and properties. 44 , and it plays a critical role in atmospheric chemistry. Atmospheric studies on benzene 50 acquired greater relevance when this volatile organic compound (VOC) became established as a 51 petrol additive, thus increasing its direct emission. Other benzene sources are the chemical 52 industry, biomass burning, cracking of aromatic hydrocarbons, solvent usage and industries 53 related to vegetable oil processing. The increasing levels of this pollutant -up to 5 g m -3 54 higher than European Directive 2000/69/EC stipulates -are of great concern not only because 55 benzene can promote carcinogenic effects and lung disease in humans but also because it is an 56 important precursor of ground-level ozone (Martin-Reviejo and Wirtz, 2005). 57The atmospheric transformations of VOCs, including aromatic hydrocarbons, have been 58 widely examined using simulation photoreactors which reproduce reactions isolated from 59 meteorological variations or dispersion (Volkamer et al., 2002 the atmospheric degradation is mainly initiated by adding the OH radical to the aromati...

Effect of air temperature on drying kinetics, vitamin C, antioxidant capacity, total phenolic content (TPC), colour due to non-enzymatic browning (NEB) and firmness during drying of blueberries was studied. Drying curves were satisfactorily simulated with the Weibull model at 50, 60, 70, 80 and 90°C. The scale parameter (β) decreased as air temperature increased and an activation energy value of 57.85 kJ mol −1 was found. Important losses of vitamin C were reported during drying for all the working temperatures (p<0.05). Although TPC decreased as air-drying temperature increased (p<0.05) in comparison to its initial value, the dehydration at high temperatures (e.g., 90°C) presented high values for these antioxidant components. Discoloration due to NEB reaction was observed at all the working temperatures showing a maximum value at 90°C (p<0.05). The radical scavenging activity showed higher antioxidant activity at high temperatures (80 and 90°C) than at low temperatures (50, 60 and 70°C) (p<0.05). A tissue firmness reduction was observed with increasing temperature (p<0.05).

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Quality assessment of pepino fruit preserved through convective dehydration was investigated in this work. The effect of process temperature (50, 60, 70, 80 and 90°C) on physicochemical properties, colour, nonenzymatic browning, vitamin C, total phenolic content, antioxidant activity and firmness of the fruit were considered. When comparing the fresh with the corresponding dehydrated pepino samples, it was shown that the drying conditions resulted in important reductions of proteins and crude fibres. Discoloration of fruit was noticeable for all treatments due to effects of non-enzymatic browning and changes in chromatic coordinates leading to a modification of the original colour. Regarding vitamin C and total phenolic content, an increase of drying temperature resulted in a considerable reduction of both initial compounds contents. Antioxidant activity showed an important decrease especially at low temperatures (e.g. 50°C). Softening of the dried product was observed for all the treatments indicating structural modifications of the fruit due to thermal process.