Glc of the silylated sugars fraction of cocoa beans revealed fructose, sorbose, glucose, sucrose, inositol, mannitol, a pentitol, and traces of two unidentified sugars. The same sugars were present in all samples, irrespective of geographic origin. Relative concentrations were, however, quite different, even among lots of the same type of bean. Most of these differences were attributed to harvesting, fermenting, and drying variables. Unfermented Sanchez beans were 1 % by wt sucrose, but fermented Bahia and Ghana beans averaged only 0.05 and 0.12% sucrose, respectively. Fermented varieties contained 2 to 16 times more fructose than glucose. The preferential consumption of the glucose moiety of sucrose during fermentation has implications important to the development of chocolate flavor during roasting. Results suggest that absorbed and occluded water-soluble constituents from the pulp contribute to the reducing sugars content of cocoa beans.A lthough cocoa beans contain only small amounts of L\ sugars, nonenzymatic browning reactions are, never--®theless, essential to the development of the typical aroma of chocolate. This is evidenced by the 30 pyrazines, 10 pyrroles, and 15 furans identified in the aroma fraction (van Elzakker and van Zutphen, 1961;Bailey et al., 1962;

Although many of the instruments planned for the TMT (Thirty Meter Telescope) have their own closely-coupled adaptive optics systems, TMT will also have a facility Adaptive Optics (AO) system, NFIRAOS, feeding three instruments on the Nasmyth platform. This Narrow-Field Infrared Adaptive Optics System, employs conventional deformable mirrors with large diameters of about 300 mm. The requirements for NFIRAOS include 1.0-2.5 microns wavelength range, 30 arcsecond diameter science field of view (FOV), excellent sky coverage, and diffraction-limited atmospheric turbulence compensation (specified at 133 nm RMS including residual telescope and science instrument errors.) The reference design for NFIRAOS includes six sodium laser guide stars over a 70 arcsecond FOV, and multiple infrared tip/tilt sensors and a natural guide star focus sensor within instruments. Larger telescopes require greater deformable mirror (DM) stroke. Although initially NFIRAOS will correct a 10 arcsecond science field, it uses two deformable mirrors in series, partly to provide sufficient stroke for atmospheric correction over the 30 m telescope aperture, but mainly to improve sky coverage by sharpening near-IR natural guide stars over a 2 arcminute diameter "technical" field. The planned upgrade to full performance includes replacing the ground-conjugated DM with a higher actuator density, and using a deformable telescope secondary mirror as a "woofer." NFIRAOS feeds three live instruments: a near-Infrared integral field Imaging spectrograph, a near-infrared echelle spectrograph, and after upgrading NFIRAOS to full multi-conjugation, a wide field (30 arcsecond) infrared camera.

International audienceMulti-object astronomical adaptive optics (MOAO) is now a mature wide-field observation mode to enlarge the adaptive-optics-corrected field in a few specific locations over tens of arcminutes. The work-scope provided by open-loop tomography and pupil conjugation is amenable to a spatio-angular linear-quadratic-Gaussian (SA-LQG) formulation aiming to provide enhanced correction across the field with improved performance over static reconstruction methods and less stringent computational complexity scaling laws. Starting from our previous work [J. Opt. Soc. Am. A 31, 101 (2014)], we use stochastic time-progression models coupled to approximate sparse measurement operators to outline a suitable SA-LQG formulation capable of delivering near optimal correction. Under the spatio-angular framework the wavefronts are never explicitly estimated in the volume, providing considerable computational savings on 10-m-class telescopes and beyond. We find that for Raven, a 10-m-class MOAO system with two science channels, the SA-LQG improves the limiting magnitude by two stellar magnitudes when both the Strehl ratio and the ensquared energy are used as figures of merit. The sky coverage is therefore improved by a factor of similar to 5. (C) 2015 Optical Society of Americ

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